leuconostoc mesenteroides cmg713: Topics by Science.gov
Production & Characterization of a Unique Dextran from an Indigenous Leuconostoc mesenteroides CMG713

PubMed Central

Sarwat, Farwa; Qader, Shah Ali Ul; Aman, Afsheen; Ahmed, Nuzhat

2008-01-01

On the basis of high enzyme activity a newly isolated strain of L. mesenteroides CMG713 was selected for dextran production. For maximum yield of dextran, effects of various parameters such as pH, temperature, sucrose concentration and incubation period were studied. L. mesenteroides CMG713 produced maximum dextran after 20 hours of incubation at 30ÂºC with 15% sucrose at pH 7.0. The molecular mass distribution of dextran produced by this strain showed that its molecular mass was about 2.0 million Da. Dextran analysis by 13C-NMR spectrometry showed no signals corresponding to any other linkages except Î±-(1â6) glycosidic linkage in the main chain, which has not been reported before. Physico-chemical properties of this unique dextran were also studied. These optimised conditions could be used for the commercial production of this unique high molecular weight dextran, which have significant industrial perspectives. PMID:18953402

Biofilm formation by strains of Leuconostoc citreum and L. mesenteroides

USDA-ARS?s Scientific Manuscript database

Aims: To compare for the first time biofilm formation among strains of Leuconostoc citreum and L. mesenteroides that produce varying types of extracellular glucans. Methods and Results: Twelve strains of Leuconostoc sp. that produce extracellular glucans were compared for their capacity to produ...

Sequence analysis of Leuconostoc mesenteroides bacteriophage (phi)1-A4 isolated from industrial vegetable fermentation

USDA-ARS?s Scientific Manuscript database

Vegetable fermentations rely on the proper succession of a variety of lactic acid bacteria (LAB) including Leuconostoc mesenteroides. L. mesenteroides initiates the fermentation, producing lactic and acetic acids, CO2, and many flavor compounds. As the fermentation proceeds, L. mesenteroides dies of...

Effects of Lactobacillus curvatus and Leuconostoc mesenteroides on Suan Cai Fermentation in Northeast China.

PubMed

Yang, Hongyan; Wu, Hao; Gao, Lijuan; Jia, Hongbai; Zhang, Yuan; Cui, Zongjun; Li, Yuhua

2016-12-28

To investigate the effects of Lactobacillus curvatus and Leuconostoc mesenteroides on suan cai (pickled Chinese cabbage) fermentation, L. curvatus and/or Ln. mesenteroides were inoculated into suan cai. Physicochemical indexes were measured, and the microbial dynamics during the fermentation were analyzed by Illumina MiSeq sequencing and quantitative polymerase chain reaction (qPCR). The results showed that inoculation with lactic acid bacteria (LAB) lowered the pH of the fermentation system more rapidly. The decrease in water-soluble carbohydrates in the inoculated treatments occurred more rapidly than in the control. The LAB counts in the control were lower than in other inoculated treatments during the first 12 days of fermentation. According to the Illumina MiSeq sequencing analyses, Firmicutes , Proteobacteria , Bacteroidetes , Actinobacteria , Cyanobacteria , Fusobacteria , and Verrucomicrobia were present in the fermentations, along with other unclassified bacteria. Generally, Firmicutes was predominant during the fermentation in all treatments. At the genus level, 16 genera were detected. The relative abundance of Lactobacillus in all inoculated treatments was higher than in the control. The relative abundance of Lactobacillus in the treatments containing L. curvatus was higher than in the Ln. mesenteroides -only treatment. The relative abundance of Leuconostoc in the Ln. mesenteroides -containing treatments increased continuously throughout the fermentation. Leuconostoc was highest in the Ln. mesenteroides -only treatment. According to the qPCR results, L. curvatus and/or Ln. mesenteroides inoculations could effectively inhabit the fermentation system. L. curvatus dominated the fermentation in the inoculated treatments.

Probiotic Properties of Leuconostoc mesenteroides Isolated from Aguamiel of Agave salmiana.

PubMed

Diana, Castro-RodrÃ­guez; Humberto, HernÃ¡ndez-SÃ¡nchez; Jorge, YÃ¡Ã±ez FernÃ¡ndez

2015-06-01

Four lactic acid bacteria, Leuconostoc mesenteroides subsp. mesenteroides, were isolated from aguamiel the sap obtained from Agave salmiana from MÃ©xico and identified by 16S rRNA gene sequence analysis. The probiotic potential of these strains was evaluated and compared with a commercial probiotic (Lactobacillus plantarum 299v) from human origin. All the strains survived the in vitro gastrointestinal simulation conditions: the stomach simulation (3 h, pH 2, 37 Â°C) and the intestinal simulation (4 h, bile salts 0.5%, 37 Â°C). All the strains showed a strong hydrophilic character with n-hexadecane and chloroform assays, and all the strains showed a mucin adhesion rate similar to that of L. plantarum 299v. The strains of L. mesenteroides subsp. mesenteroides exhibited similar antimicrobial activity against some pathogens in comparison with L. plantarum 299v. Some antibiotics inhibited the growth of the strains. L. mesenteroides subsp. mesenteroides exhibited in vitro probiotic potential, and it could be better characterized through future in vivo tests.

Production of Viscous Dextran-Containing Whey-Sucrose Broths by Leuconostoc mesenteroides ATCC 14935.

PubMed

Schwartz, R D; Bodie, E A

1984-09-01

Viscous broths were produced by growing Leuconostoc mesenteroides on a medium containing whey supplemented with sucrose. When combined with similarly produced xanthan-containing broths, a synergistic increase in viscosity was observed.

Production of Viscous Dextran-Containing Whey-Sucrose Broths by Leuconostoc mesenteroides ATCC 14935

PubMed Central

Schwartz, Robert D.; Bodie, Elizabeth A.

1984-01-01

Viscous broths were produced by growing Leuconostoc mesenteroides on a medium containing whey supplemented with sucrose. When combined with similarly produced xanthan-containing broths, a synergistic increase in viscosity was observed. PMID:16346633

Immunomodulating activity of exopolysaccharide-producing Leuconostoc mesenteroides strain NTM048 from green peas.

PubMed

Matsuzaki, C; Kamishima, K; Matsumoto, K; Koga, H; Katayama, T; Yamamoto, K; Hisa, K

2014-04-01

The present work was aimed to find novel probiotics to enhance the mucosal barrier function of humans. The effectiveness was evaluated in vitro and in vivo. Stimulation of IgA production in mucosal surfaces is one of the most beneficial traits of lactic acid bacteria (LAB) for enhancing the barrier. Therefore, 173 LAB strains were evaluated for the ability to induce IgA production using murine Peyer's patch cells. Strain NTM048 isolated from green peas showed the highest activity and was identified as Leuconostoc mesenteroides subsp. mesenteroides. This strain was found to tolerate gastrointestinal digestion and produce large amounts of exopolysaccharides, which possess IgA-inducing activity. Dietary supplementation with NTM048 induced a significant increase in the faecal IgA content and plasma IgA levels of BALB/cA mice. A gene expression analysis of Peyer's patch cells revealed that the transforming growth factor-Î² and activation-induced cytidine deaminase genes were upregulated by NTM048 intake. Strain NTM048 stimulates Peyer's patch cells to induce intestinal and systemic immune response, revealing the potential of NTM048 as a probiotic for enhancing the mucosal barrier function. This report demonstrates a food-applicable Leuconostoc mesenteroides strain secreting exopolysaccharide that shows high IgA-inducing ability. Â© 2013 The Society for Applied Microbiology.

Secreted expression of Leuconostoc mesenteroides glucansucrase in Lactococcus lactis for the production of insoluble glucans

USDA-ARS?s Scientific Manuscript database

We expressed a glucansucrase, DsrI, from Leuconostoc mesenteroides that catalyzes formation of water-insoluble glucans from sucrose in Lactococcus lactis using a nisin-controlled gene expression system. Production of DsrI was optimized using several different background vectors, signal peptides, str...

Insoluble Glucans from Planktonic and Biofilm Cultures of Mutants of Leuconostoc mesenteroides NRRL B-1355

USDA-ARS?s Scientific Manuscript database

Leuconostoc mesenteroides strain NRRL B-1355 produces the soluble exopolysaccharides alternan and dextran in planktonic cultures. Mutants of this strain are available that are deficient in the production of alternan, dextran, or both. Our recent work demonstrated that biofilms from all strains con...

Effects of mutations on the insoluble glucan synthesized by Leuconostoc mesenteroides NRRL B-1118 glucansucrase

USDA-ARS?s Scientific Manuscript database

Twelve different amino acids were each substituted for Threonine-654 in a cloned glucansucrase from Leuconostoc mesenteroides NRRL B-1118 (DSR-I). The native enzyme produces a water-insoluble glucan containing approximately 44 mol% 1,3-disubstituted a-D-glucopyranosyl units and 29 mol% 1,6-disubstit...

Production of bacteriocin by Leuconostoc mesenteroides 406 isolated from Mongolian fermented mare's milk, airag.

PubMed

Wulijideligen; Asahina, Takayuki; Hara, Kazushi; Arakawa, Kensuke; Nakano, Hiroyuki; Miyamoto, Taku

2012-10-01

The purification and characterization of a bacteriocin produced by Leuconostoc mesenteroides strain 406 that was isolated from traditional Mongolian fermented mare's milk, airag, were carried out. Leuconostoc mesenteroides strain 406 was identified on the basis of its morphological and biochemical characteristics and carbohydrate fermentation profile and by API 50 CH kit and 16S ribosomal DNA analyses. The neutral-pH cell-free supernatant of this bacterium inhibited the growth of several lactic acid bacteria and food spoilage and pathogenic organisms, including Listeria monocytogenes and Clostridium botulinum. The bacteriocin was heat-stable and not sensitive to acid and alkaline conditions, but was sensitive to several proteolytic enzymes such as pepsin, pronase E, proteinase K, trypsin, and Î±-chymotrypsin, but not catalase. Optimum bacteriocin production (4000 activity units/mL) was achieved when the strain was cultured at 25Â°C for 24-36 h in Man Rogosa Sharpe medium. The bacteriocin was partially purified by ammonium sulfate precipitation (80% saturation), dialysis (cut-off MW: 1000), and gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the bacteriocin had a molecular weight of approximately 3.3 kDa. To our knowledge, this is the first report of the isolation of a bacteriocin-producing Leuconostoc strain from airag. An application to fermented milks would be desired. Â© 2012 The Authors. Animal Science Journal Â© 2012 Japanese Society of Animal Science.

Monitoring of Leuconostoc mesenteroides DRC starter in fermented vegetable by random integration of chloramphenicol acetyltransferase gene.

PubMed

Eom, Hyun-Ju; Park, Joong Min; Seo, Min Jae; Kim, Myoung-Dong; Han, Nam Soo

2008-09-01

In 2004, Leuconostoc mesenteroides DRC was first used as a starter culture for achieving higher organoleptic effects in Korean kimchi manufacture. For a better understanding of starter growth in a mixed culture system, and for predicting starter predominance in kimchi, a monitoring system for the starter was established. The chloramphenicol resistance marker gene (cat) was randomly integrated into chromosomal DNA of L. mesenteroides DRC using a viral transposon and transposase. The DRC mutant, tDRC2, had a similar growth pattern to the host strain, with no major alteration in phenotypic characteristics. The mutant strain was inoculated into real kimchi, and monitoring of the starter population was successfully achieved. The overall predominance of Leuconostoc in kimchi inoculated with DRC followed the general growth pattern of this genus during kimchi fermentation. Our results also demonstrate the competitive ability of the DRC starter against Leuconostoc from natural flora, maintaining its predominance above 88% during the whole fermentation period. Based on this experiment, the random gene integration method using a transposon was shown to be of utility in transferring any commercial starter into a selectable and monitorable strain for simulation purposes.

Dextran synthesized by Leuconostoc mesenteroides BD1710 in tomato juice supplemented with sucrose.

PubMed

Han, Jin; Hang, Feng; Guo, Benheng; Liu, Zhenmin; You, Chunpin; Wu, Zhengjun

2014-11-04

The characteristics of the growth of Leuconostoc mesenteroides BD1710 and the synthesis of dextran in tomato juice supplemented with 15% sucrose were assayed. L. mesenteroides BD1710 could synthesize approximately 32 g L(-1) dextran in the tomato-juice-sucrose medium when cultured at 28 Â°C for 48 h, which was on the same level as the dextran yield in a chemically defined medium. The viscosity of the cultured tomato-juice-sucrose medium with various dextran contents was also measured. The results of the monosaccharide composition, molecular-weight distribution, Fourier transform infrared spectra (FTIR) and nuclear magnetic resonance spectra (NMR) showed that the polysaccharide synthesized by L. mesenteroides BD1710 in the tomato-juice-sucrose medium was dextran with a peak molecular weight of 6.35 Ã 10(5)Da, a linear backbone composed of consecutive Î±-(1 â 6)-linked d-glucopyranosyl units and approximately 6% Î±-(1 â 3) branches. Copyright Â© 2014 Elsevier Ltd. All rights reserved.

Genomic and Proteomic Characterization of Bacteriocin-Producing Leuconostoc mesenteroides Strains Isolated from Raw Camel Milk in Two Southwest Algerian Arid Zones

PubMed Central

Benmechernene, Zineb; FernÃ¡ndez-No, Inmaculada; Quintela-Baluja, Marcos; Kihal, Mebrouk; Calo-Mata, Pilar; Barros-VelÃ¡zquez, Jorge

2014-01-01

Information on the microbiology of camel milk is very limited. In this work, the genetic characterization and proteomic identification of 13 putative producing bacteriocin Leuconostoc strains exhibiting antilisterial activity and isolated from camel milk were performed. DNA sequencing of the 13 selected strains revealed high homology among the 16S rRNA genes for all strains. In addition, 99% homology with Leuconostoc mesenteroides was observed when these sequences were analysed by the BLAST tool against other sequences from reference strains deposited in the Genbank. Furthermore, the isolates were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDITOF MS) which allowed for the identification of 2 mass peaks 6242âm/z and 5118âm/z that resulted to be specific to the species L. mesenteroides. Remarkably, the phyloproteomic tree provided more intraspecific information of L. mesenteroides than phylogenetic analysis. Accordingly, phyloproteomic analysis grouped L. mesenteroides strains into different subbranches, while all L. mesenteroides isolates were grouped in the same branch according to phylogenetic analysis. This study represents, to our knowledge, the first report on the use of MALDI-TOF MS on the identification of LAB isolated from camel milk. PMID:24809059

Cloning, expression, and characterization of an insoluble glucan-producing glucansucrase from Leuconostoc mesenteroides NRRL B-1118

USDA-ARS?s Scientific Manuscript database

We have cloned a glucansucrase from the type strain of Leuconostoc mesenteroides (NRRL B-1118; ATCC 8293) and successfully expressed the enzyme in Escherichia coli. The recombinant processed enzyme has a putative sequence identical to the predicted secreted native enzyme (1,473 amino acids; 161,468...

Kocuria rosea, kocuria kristinae, leuconostoc mesenteroides as caries-causing representatives of oral microflora.

PubMed

Ananieva, Maiia M; Faustova, Mariia O; Basarab, Iaroslav O; Loban', Galina A

2017-01-01

Recently, opportunistic microflora are increasingly known to be involved in the development of pathological processes in various systems and organs. This situation promotes interest in their detailed study as causative agents of bacterial infections. To study the microbial species residing in carious cavities in acute profound caries. The study involved 14 people with a diagnosis of acute profound caries. Microbiological methods included determining species of microorganisms' cultures from carious cavities in acute profound caries. Final identification was carried out by automatic bacteriological analyzer Vitec-2compact bioMÃ©rieux. Among the bacteria isolated, Kocuria rosae, Kocuria kristinae, and Leuconostoc mesenteroides are the focus of the authors' attention due to their identification rate in the patients. These microbial species are little studied due to the lack of data on their cariogenic associations.The meticulous study of the microorganisms, isolated from carious cavities in patients with acute profound caries by automatic bacteriological analyzer Vitec-2 Systems bioMÃ©rieux, and findings on their biochemical properties allow us to conclude that Kocuria rosae, Kocuria kristinae, and Leuconostoc mesenteroides are among the microorganisms making up the microflora of carious cavities under acute profound caries and are involved in the development of the caries process.

Isolation and Characterization of Nisin-Resistant Leuconostoc mesenteroides for Use in Cabbage Fermentations

PubMed Central

Breidt, F.; Crowley, K. A.; Fleming, H. P.

1993-01-01

Leuconostoc mesenteroides strains that are resistant to high levels of nisin (up to 25,000 IU/ml in broth) were isolated. These nisin-resistant mutants were evaluated to determine their potential use as starter culture strains for cabbage fermentations. We found that some L. mesenteroides strains could be adapted to high levels of nisin resistance, while others could not. The nisin resistance trait was found to be stable for at least 35 generations, in the absence of nisin selection, for all mutants tested. The effects of nisin and salt, separately and in combination, on growth kinetics of the nisin-resistant strains were determined. Salt was the most influential factor on the specific growth rates of the mutants, and no synergistic effect between nisin and salt on specific growth rates was observed. The nisin-resistant strains were unimpaired in their ability to rapidly produce normal heterolactic fermentation end products. The use of these L. mesenteroides mutants as starter cultures in combination with nisin may extend the heterolactic phase of cabbage fermentations. PMID:16349090

Draft Genome Sequence of Leuconostoc mesenteroides 406 Isolated from the Traditional Fermented Mare Milk Airag in Tuv Aimag, Mongolia

PubMed Central

Toh, Hidehiro; Oshima, Kenshiro; Nakano, Akiyo; Hano, Chihiro; Yoshida, Saki; Nguyen, Tien Thi Thuy; Wulijideligen; Tashiro, Kosuke; Arakawa, Kensuke; Miyamoto, Taku

2016-01-01

Leuconostoc mesenteroides 406 was isolated from the traditional fermented mare milk airag in Tuv Aimag, Mongolia. This strain produces an antilisterial bacteriocin. Here, we report the draft genome sequence of this organism. PMID:27013047

Leuconostoc mesenteroides growth in food products: prediction and sensitivity analysis by adaptive-network-based fuzzy inference systems.

PubMed

Wang, Hue-Yu; Wen, Ching-Feng; Chiu, Yu-Hsien; Lee, I-Nong; Kao, Hao-Yun; Lee, I-Chen; Ho, Wen-Hsien

2013-01-01

An adaptive-network-based fuzzy inference system (ANFIS) was compared with an artificial neural network (ANN) in terms of accuracy in predicting the combined effects of temperature (10.5 to 24.5Â°C), pH level (5.5 to 7.5), sodium chloride level (0.25% to 6.25%) and sodium nitrite level (0 to 200 ppm) on the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. THE ANFIS AND ANN MODELS WERE COMPARED IN TERMS OF SIX STATISTICAL INDICES CALCULATED BY COMPARING THEIR PREDICTION RESULTS WITH ACTUAL DATA: mean absolute percentage error (MAPE), root mean square error (RMSE), standard error of prediction percentage (SEP), bias factor (Bf), accuracy factor (Af), and absolute fraction of variance (R (2)). Graphical plots were also used for model comparison. The learning-based systems obtained encouraging prediction results. Sensitivity analyses of the four environmental factors showed that temperature and, to a lesser extent, NaCl had the most influence on accuracy in predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. The observed effectiveness of ANFIS for modeling microbial kinetic parameters confirms its potential use as a supplemental tool in predictive mycology. Comparisons between growth rates predicted by ANFIS and actual experimental data also confirmed the high accuracy of the Gaussian membership function in ANFIS. Comparisons of the six statistical indices under both aerobic and anaerobic conditions also showed that the ANFIS model was better than all ANN models in predicting the four kinetic parameters. Therefore, the ANFIS model is a valuable tool for quickly predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions.

Leuconostoc Mesenteroides Growth in Food Products: Prediction and Sensitivity Analysis by Adaptive-Network-Based Fuzzy Inference Systems

PubMed Central

Wang, Hue-Yu; Wen, Ching-Feng; Chiu, Yu-Hsien; Lee, I-Nong; Kao, Hao-Yun; Lee, I-Chen; Ho, Wen-Hsien

2013-01-01

Background An adaptive-network-based fuzzy inference system (ANFIS) was compared with an artificial neural network (ANN) in terms of accuracy in predicting the combined effects of temperature (10.5 to 24.5Â°C), pH level (5.5 to 7.5), sodium chloride level (0.25% to 6.25%) and sodium nitrite level (0 to 200 ppm) on the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. Methods The ANFIS and ANN models were compared in terms of six statistical indices calculated by comparing their prediction results with actual data: mean absolute percentage error (MAPE), root mean square error (RMSE), standard error of prediction percentage (SEP), bias factor (Bf), accuracy factor (Af), and absolute fraction of variance (R 2). Graphical plots were also used for model comparison. Conclusions The learning-based systems obtained encouraging prediction results. Sensitivity analyses of the four environmental factors showed that temperature and, to a lesser extent, NaCl had the most influence on accuracy in predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. The observed effectiveness of ANFIS for modeling microbial kinetic parameters confirms its potential use as a supplemental tool in predictive mycology. Comparisons between growth rates predicted by ANFIS and actual experimental data also confirmed the high accuracy of the Gaussian membership function in ANFIS. Comparisons of the six statistical indices under both aerobic and anaerobic conditions also showed that the ANFIS model was better than all ANN models in predicting the four kinetic parameters. Therefore, the ANFIS model is a valuable tool for quickly predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. PMID:23705023

Draft Genome Sequence of Leuconostoc mesenteroides 406 Isolated from the Traditional Fermented Mare Milk Airag in Tuv Aimag, Mongolia.

PubMed

Morita, Hidetoshi; Toh, Hidehiro; Oshima, Kenshiro; Nakano, Akiyo; Hano, Chihiro; Yoshida, Saki; Nguyen, Tien Thi Thuy; Wulijideligen; Tashiro, Kosuke; Arakawa, Kensuke; Miyamoto, Taku

2016-03-24

Leuconostoc mesenteroides406 was isolated from the traditional fermented mare milk airag in Tuv Aimag, Mongolia. This strain produces an antilisterial bacteriocin. Here, we report the draft genome sequence of this organism. Copyright Â© 2016 Morita et al.

Draft Genome Sequence of Leuconostoc mesenteroides 213M0, Isolated from Traditional Fermented Mare Milk Airag in Bulgan Aimag, Mongolia

PubMed Central

Toh, Hidehiro; Oshima, Kenshiro; Nakano, Akiyo; Hano, Chihiro; Yoshida, Saki; Bolormaa, Tsognemekh; Burenjargal, Sedkhuu; Nguyen, Co Thi Kim; Tashiro, Kosuke; Arakawa, Kensuke; Miyamoto, Taku

2016-01-01

Leuconostoc mesenteroides 213M0 was isolated from traditional fermented mare milk airag in Bulgan Aimag, Mongolia. This strain produces a listericidal bacteriocin-like inhibitory substance. Here, we report the draft genome sequence of this organism. PMID:27034488

Draft Genome Sequence of Leuconostoc mesenteroides 213M0, Isolated from Traditional Fermented Mare Milk Airag in Bulgan Aimag, Mongolia.

PubMed

Morita, Hidetoshi; Toh, Hidehiro; Oshima, Kenshiro; Nakano, Akiyo; Hano, Chihiro; Yoshida, Saki; Bolormaa, Tsognemekh; Burenjargal, Sedkhuu; Nguyen, Co Thi Kim; Tashiro, Kosuke; Arakawa, Kensuke; Miyamoto, Taku

2016-03-31

Leuconostoc mesenteroides213M0 was isolated from traditional fermented mare milk airag in Bulgan Aimag, Mongolia. This strain produces a listericidal bacteriocin-like inhibitory substance. Here, we report the draft genome sequence of this organism. Copyright Â© 2016 Morita et al.

Draft Genome Sequence of Leuconostoc mesenteroides P45 Isolated from Pulque, a Traditional Mexican Alcoholic Fermented Beverage

PubMed Central

Riveros-Mckay, Fernando; Campos, Itzia; Giles-GÃ³mez, Martha; BolÃ­var, Francisco

2014-01-01

Leuconostoc mesenteroides P45 was isolated from the traditional Mexican pulque beverage. We report its draft genome sequence, assembled in 6 contigs consisting of 1,874,188Â bp and no plasmids. Genome annotation predicted a total of 1,800 genes, 1,687 coding sequences, 52 pseudogenes, 9 rRNAs, 51 tRNAs, 1 noncoding RNA, and 44 frameshifted genes. PMID:25377708

Effect of a single point mutation on the interaction of glucans with a glucansucrase from Leuconostoc mesenteroides NRRL B-1118

USDA-ARS?s Scientific Manuscript database

The type strain of the lactic acid bacterium Leuconostoc mesenteroides produces a water-insoluble glucan from sucrose via an extracellular glucansucrase. Substitution of an amino acid that is coupled with the +2 subsite adjacent to the transition stabilizer of this glucansucrase, results in signific...

Pre-treatment step with Leuconostoc mesenteroides or L. pseudomesenteroides strains removes furfural from Zymomonas mobilis ethanolic fermentation broth.

PubMed

Hunter, William J; Manter, Daniel K

2014-10-01

Furfural is an inhibitor of growth and ethanol production by Zymomonas mobilis. This study used a naturally occurring (not GMO) biological pre-treatment to reduce that amount of furfural in a model fermentation broth. Pre-treatment involved inoculating and incubating the fermentation broth with strains of Leuconostoc mesenteroides or Leuconostoc pseudomesenteroides. The Leuconostoc strains converted furfural to furfuryl alcohol without consuming large amounts of dextrose in the process. Coupling this pre-treatment to ethanolic fermentation reduced furfural in the broth and improved growth, dextrose uptake and ethanol formation. Pre-treatment permitted ethanol formation in the presence of 5.2 g L(-1) furfural, which was otherwise inhibitive. The pre-treatment and presence of the Leuconostoc strains in the fermentation broth did not interfere with Z. mobilis ethanolic fermentation or the amounts of ethanol produced. The method suggests a possible technique for reducing the effect that furfural has on the production of ethanol for use as a biofuel. Published by Elsevier Ltd.

Draft Genome Sequence of Leuconostoc mesenteroides P45 Isolated from Pulque, a Traditional Mexican Alcoholic Fermented Beverage.

PubMed

Riveros-Mckay, Fernando; Campos, Itzia; Giles-GÃ³mez, Martha; BolÃ­var, Francisco; Escalante, Adelfo

2014-11-06

Leuconostoc mesenteroides P45 was isolated from the traditional Mexican pulque beverage. We report its draft genome sequence, assembled in 6 contigs consisting of 1,874,188Â bp and no plasmids. Genome annotation predicted a total of 1,800 genes, 1,687 coding sequences, 52 pseudogenes, 9 rRNAs, 51 tRNAs, 1 noncoding RNA, and 44 frameshifted genes. Copyright Â© 2014 Riveros-Mckay et al.

Sequence Analysis of Leuconostoc mesenteroides Bacteriophage Î¦1-A4 Isolated from an Industrial Vegetable Fermentationâ¿

PubMed Central

Lu, Z.; Altermann, E.; Breidt, F.; Kozyavkin, S.

2010-01-01

Vegetable fermentations rely on the proper succession of a variety of lactic acid bacteria (LAB). Leuconostoc mesenteroides initiates fermentation. As fermentation proceeds, L. mesenteroides dies off and other LAB complete the fermentation. Phages infecting L. mesenteroides may significantly influence the die-off of L. mesenteroides. However, no L. mesenteroides phages have been previously genetically characterized. Knowledge of more phage genome sequences may provide new insights into phage genomics, phage evolution, and phage-host interactions. We have determined the complete genome sequence of L. mesenteroides phage Î¦1-A4, isolated from an industrial sauerkraut fermentation. The phage possesses a linear, double-stranded DNA genome consisting of 29,508 bp with a G+C content of 36%. Fifty open reading frames (ORFs) were predicted. Putative functions were assigned to 26 ORFs (52%), including 5 ORFs of structural proteins. The phage genome was modularly organized, containing DNA replication, DNA-packaging, head and tail morphogenesis, cell lysis, and DNA regulation/modification modules. In silico analyses showed that Î¦1-A4 is a unique lytic phage with a large-scale genome inversion (â¼30% of the genome). The genome inversion encompassed the lysis module, part of the structural protein module, and a cos site. The endolysin gene was flanked by two holin genes. The tail morphogenesis module was interspersed with cell lysis genes and other genes with unknown functions. The predicted amino acid sequences of the phage proteins showed little similarity to other phages, but functional analyses showed that Î¦1-A4 clusters with several Lactococcus phages. To our knowledge, Î¦1-A4 is the first genetically characterized L. mesenteroides phage. PMID:20118355

Modelling the growth of Leuconostoc mesenteroides by Artificial Neural Networks.

PubMed

GarcÃ­a-Gimeno, R M; HervÃ¡s-MartÃ­nez, C; RodrÃ­guez-PÃ©rez, R; Zurera-Cosano, G

2005-12-15

The combined effect of temperature (10.5 to 24.5 degrees C), pH level (5.5 to 7.5), sodium chloride level (0.25% to 6.25%) and sodium nitrite level (0 to 200 ppm) on the predicted specific growth rate (Gr), lag-time (Lag) and maximum population density (yEnd) of Leuconostoc mesenteroides under aerobic and anaerobic conditions, was studied using an Artificial Neural Network-based model (ANN) in comparison with Response Surface Methodology (RS). For both aerobic and anaerobic conditions, two types of ANN model were elaborated, unidimensional for each of the growth parameters, and multidimensional in which the three parameters Gr, Lag, and yEnd are combined. Although in general no significant statistical differences were observed between both types of model, we opted for the unidimensional model, because it obtained the lowest mean value for the standard error of prediction for generalisation. The ANN models developed provided reliable estimates for the three kinetic parameters studied; the SEP values in aerobic conditions ranged from between 2.82% for Gr, 6.05% for Lag and 10% for yEnd, a higher degree accuracy than those of the RS model (Gr: 9.54%; Lag: 8.89%; yEnd: 10.27%). Similar results were observed for anaerobic conditions. During external validation, a higher degree of accuracy (Af) and bias (Bf) were observed for the ANN model compared with the RS model. ANN predictive growth models are a valuable tool, enabling swift determination of L. mesenteroides growth parameters.

Corrosion protection of low-carbon steel using exopolysaccharide coatings from Leuconostoc mesenteroides.

PubMed

Finkenstadt, Victoria L; CÃ´tÃ©, Gregory L; Willett, J L

2011-06-01

Corrosion of metals is a serious and challenging problem faced worldwide by industry. Purified Leuconostoc mesenteroides exopolysaccharide (EPS) coatings, cast from aqueous solution, inhibited the corrosion of low-carbon steel as determined by electrochemical impedance spectroscopy (EIS). There were two different corrosion behaviors exhibited when EPS films from different strains were cast onto the steel. One EPS coating reacted immediately with the steel substrate to form an iron (III) oxide layer ("rust") during the drying process while another did not. The samples that did not flash corrode had higher corrosion inhibition and formed an iron (II) passivation layer during EIS testing that persisted after the cells were disassembled. Corrosion inhibition was strain-specific as polysaccharides with similar structure did not have the same corrosion potential.

Characterization of the major dehydrogenase related to d-lactic acid synthesis in Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293.

PubMed

Li, Ling; Eom, Hyun-Ju; Park, Jung-Mi; Seo, Eunyoung; Ahn, Ji Eun; Kim, Tae-Jip; Kim, Jeong Hwan; Han, Nam Soo

2012-10-10

Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293 is a lactic acid bacterium that converts pyruvate mainly to d-(-)-lactic acid by using d-(-)-lactate dehydrogenase (ldhD). The aim of this study was to identify the gene responsible for d-lactic acid formation in this organism and to characterize the enzyme to facilitate the production of optically pure d-lactic acid. A genomic analysis of L. mesenteroides ATCC 8293 revealed that 7 genes encode lactate-related dehydrogenase. According to transcriptomic, proteomic, and phylogenetic analyses, LEUM_1756 was the major gene responsible for the production of d-lactic acid. The LEUM_1756 gene, of 996bp and encoding 332 amino acids (36.5kDa), was cloned and overexpressed in Escherichia coli BL21(DE3) Star from an inducible pET-21a(+) vector. The enzyme was purified by Ni-NTA column chromatography and showed a specific activity of 4450U/mg, significantly higher than those of other previously reported ldhDs. The gel permeation chromatography analysis showed that the purified enzyme exists as tetramers in solution and this was the first report among lactic acid bacteria. The pH and temperature optima were pH 8.0 and 30Â°C, respectively, for the pyruvate reduction reaction, and pH 11.0 and 20Â°C, respectively, for the lactate oxidation reaction. The K(m) kinetic parameters for pyruvate and lactate were 0.58mM and 260mM, respectively. In addition, the k(cat) values for pyruvate and lactate were 2900s(-1) and 2280s(-1), respectively. The enzyme was not inhibited by Ca(2+), Co(2+), Cu(2+), Mg(2+), Mn(2+), Na(+), or urea, but was inhibited by 1mM Zn(2+) and 1mM SDS. Copyright Â© 2012 Elsevier Inc. All rights reserved.

Enzyme-resistant isomalto-oligosaccharides produced from Leuconostoc mesenteroides NRRL B-1426 dextran hydrolysis for functional food application.

PubMed

Kothari, Damini; Goyal, Arun

2016-07-01

The extracellular dextransucrase from Leuconostoc mesenteroides NRRL B-1426 was produced and purified using polyethylene glycol fractionation. In our earlier study, it was reported that L. mesenteroides dextransucrase synthesizes a high-molecular mass dextran (>2Â ÃÂ 10(6) Â Da) with â¼85.5% Î±-(1â6) linear and â¼14.5% Î±-(1â3) branched linkages. Isomalto-oligosaccharides (IMOs) were synthesized through depolymerization of dextran by the action of dextranase. The degree of polymerization of IMOs was 2-10 as confirmed by mass spectrometry. The nuclear magnetic resonance spectroscopic analysis revealed the presence of Î±-(1â3) linkages in the synthesized IMOs. The IMOs were resistant to dextranase, Î±-glucosidase, and Î±-amylase, and therefore can have potential application as food additives in the functional foods. Â© 2015 International Union of Biochemistry and Molecular Biology, Inc.

Inhibitory effects of autolysate of Leuconostoc mesenteroides isolated from kimoto on melanogenesis.

PubMed

Kondo, Sayo; Takahashi, Toshinari; Yoshida, Kazutoshi; Mizoguchi, Haruhiko

2012-10-01

We investigated the inhibitory effects of the autolysate of Leuconostoc mesenteroides, a lactic acid bacterium isolated from sake mash, on melanogenesis in B16F0 murine melanoma cells and a human skin model. The autolysate: induced a decrease in melanin content in B16F0 murine melanoma cells and a 17%, 36%, 41% and 58% decrease in the human skin model by the application of 0.125, 1.25, 6.25, and 12.5Â mg/tissue in total; decreased tyrosinase activity to 71%, 46% and 29% of control in B16F0 cells with 0.1, 0.2 and 0.4Â mg/ml-medium respectively, but did not inhibit tyrosinase activity under cell-free conditions; decreased amount of tyrosinase in a dose-dependent manner from 74% with 0.1Â mg/ml to 33% with 0.4Â mg/ml; and decreased amount of tyrosinase mRNA to 80-90% with 0.2-0.4Â mg/ml-medium. As the decrease in tyrosinase mRNA levels could not fully account for the reduction in protein, we suggest that the autolysate had post-transcriptional effects rather than transcription inhibition. Our results indicate that the autolysate of L.Â mesenteroides has potential therapeutic use as an effective anti-melanogenic agent. Copyright Â© 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Structural analysis and characterization of dextran produced by wild and mutant strains of Leuconostoc mesenteroides.

PubMed

Siddiqui, Nadir Naveed; Aman, Afsheen; Silipo, Alba; Qader, Shah Ali Ul; Molinaro, Antonio

2014-01-01

An exopolysaccharide known as dextran was produced by Leuconostoc mesenteroides KIBGE-IB22 (wild) and L. mesenteroides KIBGE-IB22M20 (mutant). The structure was characterized using FTIR, (1)H NMR, (13)C NMR and 2D NMR spectroscopic techniques, whereas surface morphology was analyzed using SEM. A clear difference in the spectral chemical shift patterns was observed in both samples. All the spectral data indicated that the exopolysaccharide produced by KIBGE-IB22 is a mixture of two biopolymers. One was dextran in Î±-(1 â 6) configuration with a small proportion of Î±-(1 â 3) branching and the other was levan containing Î²-(2 â 6) fructan fructofuranosyl linkages. However, remarkably the mutant only produced dextran without any concomitant production of levan. Study suggested that the property of KIBGE-IB22M20, regarding improved production of high molecular weight dextran in a shorter period of fermentation time without any contamination of other exopolysaccharide, could be employed to make the downstream process more feasible and cost effective on large scale. Copyright Â© 2013 Elsevier Ltd. All rights reserved.

Gluco-oligosaccharides synthesized by glucosyltransferases from constitutive mutants of Leuconostoc mesenteroides strain Lm 28.

PubMed

Iliev, I; Vassileva, T; Ignatova, C; Ivanova, I; HaertlÃ©, T; Monsan, P; Chobert, J-M

2008-01-01

To find different types of glucosyltransferases (GTFs) produced by Leuconostoc mesenteroides strain Lm 28 and its mutant forms, and to check the effectiveness of gluco-oligosaccharide synthesis using maltose as the acceptor. Constitutive mutants were obtained after chemical mutagenesis by ethyl methane sulfonate. Lm M281 produced more active GTFs than that obtained by the parental strain cultivated on sucrose. GTF from Lm M286 produced a resistant glucan, based on endo-dextranase and amyloglucosidase hydrolysis. The extracellular enzymes from Lm M286 catalyse acceptor reactions and transfer the glucose unit from sucrose to maltose to produce gluco-oligosaccharides (GOS). By increasing the sucrose/maltose ratio, it was possible to catalyse the synthesis of oligosaccharides of increasing degree of polymerization (DP). Different types of GTFs (dextransucrase, alternansucrase and levansucrase) were produced from new constitutive mutants of Leuc. mesenteroides. GTFs from Lm M286 can catalyse the acceptor reaction in the presence of maltose, leading to the synthesis of branched oligosaccharides. Conditions were optimized to synthesize GOS by using GTFs from Lm M286, with the aim of producing maximum quantities of branched-chain oligosaccharides with DP 3-5. This would allow the use of the latter as prebiotics.

Development and use of a selective medium for isolation of Leuconostoc spp. from vegetables and dairy products.

PubMed Central

Benkerroum, N; Misbah, M; Sandine, W E; Elaraki, A T

1993-01-01

A selective medium (LUSM medium) for the isolation of Leuconostoc spp. was developed. This medium contained 1.0% glucose, 1.0% Bacto Peptone (Difco), 0.5% yeast extract (BBL), 0.5% meat extract (Difco), 0.25% gelatin (Difco), 0.5% calcium lactate, 0.05% sorbic acid, 75 ppm of sodium azide (Sigma), 0.25% sodium acetate, 0.1% (vol/vol) Tween 80, 15% tomato juice, 30 micrograms of vancomycin (Sigma) per ml, 0.20 microgram of tetracycline (Serva) per ml, 0.5 mg of cysteine hydrochloride per ml, and 1.5% agar (Difco). LUSM medium was used successfully for isolation and enumeration of Leuconostoc spp. in dairy products and vegetables. Of 116 colony isolates obtained from fresh raw milk, curdled milk, or various vegetables, 115 were identified as members of the genus Leuconostoc. A total of 89 of these isolates were identified to species; 13.5% of the isolates were Leuconostoc cremoris, 7.9% were Leuconostoc mesenteroides subsp. mesenteroides, 11.2% were Leuconostoc mesenteroides subsp. dextranicum, 16.9% were Leuconostoc mesenteroides subsp. paramesenteroides, 10.1% were leuconostoc lactis, and 40.4% were Leuconostoc oenos. When we compared the counts obtained for two Leuconostoc strains, Leuconostoc dextranicum 181 and L. cremoris JLL8, on MRS agar and LUSM medium, we found no significant difference between the values obtained on the two media. PMID:8434926

Genetic diversity analysis of Leuconostoc mesenteroides from Korean vegetables and food products by multilocus sequence typing.

PubMed

Sharma, Anshul; Kaur, Jasmine; Lee, Sulhee; Park, Young-Seo

2018-06-01

In the present study, 35 Leuconostoc mesenteroides strains isolated from vegetables and food products from South Korea were studied by multilocus sequence typing (MLST) of seven housekeeping genes (atpA, groEL, gyrB, pheS, pyrG, rpoA, and uvrC). The fragment sizes of the seven amplified housekeeping genes ranged in length from 366 to 1414Â bp. Sequence analysis indicated 27 different sequence types (STs) with 25 of them being represented by a single strain indicating high genetic diversity, whereas the remaining 2 were characterized by five strains each. In total, 220 polymorphic nucleotide sites were detected among seven housekeeping genes. The phylogenetic analysis based on the STs of the seven loci indicated that the 35 strains belonged to two major groups, A (28 strains) and B (7 strains). Split decomposition analysis showed that intraspecies recombination played a role in generating diversity among strains. The minimum spanning tree showed that the evolution of the STs was not correlated with food source. This study signifies that the multilocus sequence typing is a valuable tool to access the genetic diversity among L. mesenteroides strains from South Korea and can be used further to monitor the evolutionary changes.

Response of Leuconostoc strains against technological stress factors: Growth performance and volatile profiles.

PubMed

Cicotello, JoaquÃ­n; Wolf, Irma V; D'Angelo, Luisa; Guglielmotti, Daniela M; Quiberoni, Andrea; SuÃ¡rez, Viviana B

2018-08-01

The ability of twelve strains belonging to three Leuconostoc species (Leuconostoc mesenteroides, Leuconostoc lactis and Leuconostoc pseudomesenteroides) to grow under diverse sub-lethal technological stress conditions (cold, acidic, alkaline and osmotic) was evaluated in MRS broth. Two strains, Leuconostoc lactis Ln N6 and Leuconostoc mesenteroides Ln MB7, were selected based on their growth under sub-lethal conditions, and volatile profiles in RSM (reconstituted skim milk) at optimal and under stress conditions were analyzed. Growth rates under sub-lethal conditions were strain- and not species-dependent. Volatilomes obtained from the two strains studied were rather diverse. Particularly, Ln N6 (Ln. lactis) produced more ethanol and acetic acid than Ln MB7 (Ln. mesenteroides) and higher amounts and diversity of the rest of volatile compounds as well, at all times of incubation. For the two strains studied, most of stress conditions applied diminished the amounts of ethanol and acetic acid produced and the diversity and levels of the rest of volatile compounds. These results were consequence of the different capacity of the strains to grow under each stress condition tested. Copyright Â© 2018 Elsevier Ltd. All rights reserved.

Tandem dye-ligand chromatography and biospecific elution applied to the purification of glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides.

PubMed Central

Hey, Y; Dean, P D

1983-01-01

1. A total of 65 immobilized triazine dyes were screened for their ability to purify the dual-nucleotide-specific glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides. From this screen a 'negative' (Matrex Gel Purple A) and a 'positive' (Matrex Gel Orange B) adsorbent were found to be the best in terms of overall purification and yield and were therefore combined to give the best purification. 2. Glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides was purified approx. 56-fold in a two-step tandem chromatographic system using Matrex Gel Purple A followed by Matrex Gel Orange B chromatography to a specific activity of 228 units/mg of protein in a final yield of 73%. 3. A study of the elution characteristics of glucose-6-phosphate dehydrogenase bound to Matrex Gel Orange B by KCl (pulse and gradient) and biospecific eluents (pulse) was carried out. NADP+, NADPH and adenosine 2',5'-bisphosphate were found to be the only effective biospecific eluents. A pulse of 50 microM-NADP+ (1/2 column vol.) was found to give a better purification than a 0-1 M-KCl gradient and therefore was the preferred method of elution. 4. Presaturation of the enzyme with various nucleotides was carried out to determine the effect on the subsequent binding of glucose-6-phosphate dehydrogenase to Matrex Gel Orange B. The results of these and biospecific-elution studies lead us to propose two possible schemes to explain the mechanism of the dye-protein interaction. 5. Reusability, capacity of the adsorbent and effect of varying the ligand concentration were also studied in the purification of glucose-6-phosphate dehydrogenase on Matrex Gel Orange B. Images Fig. 1. PMID:6847623

Tandem dye-ligand chromatography and biospecific elution applied to the purification of glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides.

PubMed

Hey, Y; Dean, P D

1983-02-01

1. A total of 65 immobilized triazine dyes were screened for their ability to purify the dual-nucleotide-specific glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides. From this screen a 'negative' (Matrex Gel Purple A) and a 'positive' (Matrex Gel Orange B) adsorbent were found to be the best in terms of overall purification and yield and were therefore combined to give the best purification. 2. Glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides was purified approx. 56-fold in a two-step tandem chromatographic system using Matrex Gel Purple A followed by Matrex Gel Orange B chromatography to a specific activity of 228 units/mg of protein in a final yield of 73%. 3. A study of the elution characteristics of glucose-6-phosphate dehydrogenase bound to Matrex Gel Orange B by KCl (pulse and gradient) and biospecific eluents (pulse) was carried out. NADP+, NADPH and adenosine 2',5'-bisphosphate were found to be the only effective biospecific eluents. A pulse of 50 microM-NADP+ (1/2 column vol.) was found to give a better purification than a 0-1 M-KCl gradient and therefore was the preferred method of elution. 4. Presaturation of the enzyme with various nucleotides was carried out to determine the effect on the subsequent binding of glucose-6-phosphate dehydrogenase to Matrex Gel Orange B. The results of these and biospecific-elution studies lead us to propose two possible schemes to explain the mechanism of the dye-protein interaction. 5. Reusability, capacity of the adsorbent and effect of varying the ligand concentration were also studied in the purification of glucose-6-phosphate dehydrogenase on Matrex Gel Orange B.

Long-term adaptive evolution of Leuconostoc mesenteroides for enhancement of lactic acid tolerance and production.

PubMed

Ju, Si Yeon; Kim, Jin Ho; Lee, Pyung Cheon

2016-01-01

Lactic acid has been approved by the United States Food and Drug Administration as Generally Regarded As Safe (GRAS) and is commonly used in the cosmetics, pharmaceutical, and food industries. Applications of lactic acid have also emerged in the plastics industry. Lactic acid bacteria (LAB), such as Leuconostoc and Lactobacillus , are widely used as lactic acid producers for food-related and biotechnological applications. Nonetheless, industrial mass production of lactic acid in LAB is a challenge mainly because of growth inhibition caused by the end product, lactic acid. Thus, it is important to improve acid tolerance of LAB to achieve balanced cell growth and a high titer of lactic acid. Recently, adaptive evolution has been employed as one of the strategies to improve the fitness and to induce adaptive changes in bacteria under specific growth conditions, such as acid stress. Wild-type Leuconostoc mesenteroides was challenged long term with exogenously supplied lactic acid, whose concentration was increased stepwise (for enhancement of lactic acid tolerance) during 1Â year. In the course of the adaptive evolution at 70Â g/L lactic acid, three mutants (LMS50, LMS60, and LMS70) showing high specific growth rates and lactic acid production were isolated and characterized. Mutant LMS70, isolated at 70Â g/L lactic acid, increased d-lactic acid production up to 76.8Â g/L, which was twice that in the wild type (37.8Â g/L). Proteomic, genomic, and physiological analyses revealed that several possible factors affected acid tolerance, among which a mutation of ATPase Îµ subunit (involved in the regulation of intracellular pH) and upregulation of intracellular ammonia, as a buffering system, were confirmed to contribute to the observed enhancement of tolerance and production of d-lactic acid. During adaptive evolution under lethal stress conditions, the fitness of L. mesenteroides gradually increased to accumulate beneficial mutations according to the stress level. The

Controlling Listeria monocytogenes and Leuconostoc mesenteroides in Uncured Deli-style Turkey Breast Using a Clean Label Antimicrobial.

PubMed

Weyker, Robert E; Glass, Kathleen A; Milkowski, Andrew L; Seman, Dennis L; Sindelar, Jeffrey J

2016-03-01

Interest in natural/organic meat products has resulted in the need to validate the effectiveness of clean label antimicrobials to increase safety and shelf life of these products. A Response Surface Methodology (RSM) was used to investigate the effects of varying levels of moisture, pH, and a commercial "clean-label" antimicrobial (cultured sugar-vinegar blend; CSVB) on the growth rate of Listeria monocytogenes and Leuconostoc mesenteroides in uncured turkey stored at 4 Â°C for 16 wk. Twenty treatment combinations of moisture (60% to 80%), pH (5.8 to 6.4), and CSVB (2.5% to 5.0%) were evaluated during phase I to develop growth curves for both microbe types, whereas the interactive effects of pH (5.8 to 6.4) and CSVB (0.0 to 4.75) were tested in 16 treatment combinations during Phase II at a single moisture level using L. monocytogenes only. CSVB inhibited L. monocytogenes growth in 14 of the 20 treatments tested in Phase I and in 12 of the 16 treatments in Phase II through 16 and 8 wk, respectively. In contrast, CSVB had little effect on L. mesenteroides, with growth inhibited in only 4 of 20 treatments in Phase I and was therefore not tested further in Phase II. Significant interactions of the RSM design coefficients yielded a predictive model for L. mesenteroides growth rate, but due to lack of growth, no growth rate model was developed for L. monocytogenes. CSVB was found to be an effective antilisteral antimicrobial, while having little effect on a spoilage microorganism. Â© 2016 Institute of Food TechnologistsÂ®

Reduction of soybean oligosaccharides and properties of alpha-D-galactosidase from Lactobacillus curvatus R08 and Leuconostoc mesenteroides [corrected] JK55.

PubMed

Yoon, Mi Young; Hwang, Han-Joon

2008-09-01

This study was undertaken to investigate the potential for reducing non-digestive oligosaccharides (NDO) in soy foods, as well as the influence of exogenous conditions on intracellular alpha-galactosidase (alpha-Gal) producing lactic acid bacteria. Two strains, Lactobacillus curvatus R08 and Leuconostoc mesenteroides [corrected]JK55, showed the highest levels of raffinose degrading activity at over 40 U mL(-1), and presented maximum activities during the stationary phase in a medium where raffinose was the only carbon source. Raffinose was the most effective inducer, followed by melibiose, and galactose; the enzymes were partially inhibited by fructose and sucrose. On the other hand, limited activity was observed in glucose. The strains displayed optimum activity levels at neutral pH and a 35-37 degrees C temperature range. The alpha-Gal activities of L. curvatus R08 and Leu. mesenteroides [corrected] JK55 were maintained at pH 6.5-10.0. The activity of the alpha-Gal enzyme was stable in a relatively broad range of temperatures from 0 to 40 degrees C for 3h. In soymilk, Leu. mesenteroides [corrected] JK55 and L. curvatus R08 completely hydrolyzed the NDO after 18-24h of fermentation. The abilities of L. curvatus R08 and Leu. mesenteroides [corrected] JK55 to degrade raffinose sugars and, particularly, to produce organic acids from sugar, could contribute to reductions in the anti-nutritional properties of soy, and to the accumulation of compounds with beneficial properties during food processing. Furthermore, this study provides the optimum conditions to induce alpha-Gal from these strains.

In vitro and in vivo probiotic assessment of Leuconostoc mesenteroides P45 isolated from pulque, a Mexican traditional alcoholic beverage.

PubMed

Giles-GÃ³mez, Martha; Sandoval GarcÃ­a, Jorge Giovanni; Matus, Violeta; Campos Quintana, Itzia; BolÃ­var, Francisco; Escalante, Adelfo

2016-01-01

Pulque is a Mexican traditional alcoholic, non-distilled, fermented beverage produced by the fermentation of the sap, known as aguamiel, extracted from several maguey (Agave) species. Pulque has traditionally been considered a healthy beverage due to its nutrient content and also a traditional medicine for the treatment of gastrointestinal disorders and intestinal infections. During pulque fermentation, the development of acidity, alcohol and viscosity define its final sensorial properties, developing an enriched environment where dominant lactic acid bacteria (LAB), including diverse Leuconostoc species, are present. Because traditional pulque is consumed directly from the fermentation vessel, the naturally associated LAB are ingested and reach the human small intestine alive. Here, we report the in vitro and in vivo probiotic assessment of Leuconostoc mesenteroides strain P45 isolated from pulque. This isolated LAB species exhibited lysozyme, acid (pH 3.5) and bile salts (0.1 and 0.3Â % oxgall) resistance. Antibacterial activity against the pathogens Listeria monocytogenes, enteropathogenic Escherichia coli, Salmonella enterica serovar Typhi and S. enterica serovar Typhimurium were observed in assays involving cell-to-cell contact, cell-free 2Ã concentrated supernatants and cell-to-cell contact under exopolysaccharide-producing conditions. The in vivo probiotic assessment showed an anti-infective activity of L. mesenteroides P45 against S. enterica serovar Typhimurium in challenged male and female BALB/c mice. Analysis of the available genome sequence of strain P45 allowed identified a pre-bacteriocin coding gene and six peptidoglycan hydrolase enzymes, probably involved in the antimicrobial activity of this strain. The results presented in this study support some potential microbial mechanisms associated with the beneficial effects on human health of this LAB involved in the fermentation of pulque.

Change in Flavonoid Composition and Antioxidative Activity during Fermentation of Onion (Allium cepa L.) by Leuconostoc mesenteroides with Different Salt Concentrations.

PubMed

Lee, Yu Geon; Cho, Jeong-Yong; Kim, Young-Min; Moon, Jae-Hak

2016-06-01

The aim of this study is to investigate the change in flavonoid composition and antioxidative activity during fermentation of onion (Allium cepa L.) by Leuconostoc mesenteroides with different NaCl concentrations. In order to qualify and quantify the flavonoids during fermentation of onion, 7 flavonoids, [quercetin 3,7-O-Î²-d-diglucopyranoside (Q3,7G), quercetin 3,4'-O-Î²-d-diglucopyranoside (Q3,4'G), quercetin 3-O-Î²-d-glucopyranoside (Q3G), quercetin 4'-O-Î²-d-glucopyranoside (Q4'G), isorhamnetin 3-O-Î²-d-glucopyranoside (IR3G), quercetin (Q), and isorhamnetin (IR)], were isolated and identified from onion. During fermentation, the contents of flavonoid glucosides (Q3,7G, Q3,4'G, Q3G, Q4'G, and IR3G) gradually decreased, whereas the contents of flavonoid aglycones (Q, IR) gradually increased. Decline rates of the flavonoid glucosides increased with the addition of L. mesenteroides. Furthermore, the activity of Î²-glucosidase, which is produced by L. mesenteroides, is dose-dependently inhibited with different NaCl concentrations during fermentation. The presence of L. mesenteroides enhanced the antioxidative activity of onion as demonstrated using the 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and reducing power assays. The enhancement of antioxidative activity was considered because the content of flavonoid aglycones increased during fermentation. However, the addition of NaCl may decrease the antioxidative activity; we surmise that this phenomenon occurs because of the inhibition of Î²-glucosidase by NaCl. Therefore, we conclude that the addition of NaCl may be useful for the regulation of antioxidative activity via the control of Î²-glucosidase action, during the fermentation of flavonoid glucoside-rich foods. Â© 2016 Institute of Food TechnologistsÂ®

Purification and characterization of a bacteriocin from an oenological strain of Leuconostoc mesenteroides subsp. cremoris.

PubMed

DÃ¼ndar, Halil; Salih, Bekir; BozoÄlu, Faruk

2016-05-18

Malolactic fermentation (MLF), which improves organoleptic properties and biologic stability of some wines, may cause wine spoilage if uncontrolled. Bacteriocins were reported as efficient preservatives to control MLF through their bactericidal effect on malolactic bacteria. Leuconostoc mesenteroides subsp. cremoris W3 isolated from wine produces an inhibitory substance that is bactericidal against malolactic bacteria in model wine medium. Treatment of the culture supernatant of strain W3 with proteases eliminated the inhibitory activity, which proved that it is a true bacteriocin and we tentatively termed it mesentericin W3. The bacteriocin inhibited the growth of food-borne pathogenic bacteria such as Enterococcus faecalis, Listeria monocytogenes, and malolactic bacteria. It was active over a wide pH range and stable to organic solvents and heat. Mesentericin W3 was purified to homogeneity by a pH-mediated cell adsorption-desorption method, cation exchange, hydrophobic interaction, and reverse-phase chromatography. Matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectroscopy (MS) and partial amino acid sequence analysis revealed that mesentericin W3 was identical to mesentericin Y105.

Antibiotic Susceptibility Profiles of Dairy Leuconostoc, Analysis of the Genetic Basis of Atypical Resistances and Transfer of Genes In Vitro and in a Food Matrix

PubMed Central

Delgado, Susana; AlegrÃ­a, Ãngel; Salvetti, Elisa; Felis, Giovanna E.; Mayo, Baltasar; Torriani, Sandra

2016-01-01

In spite of a global concern on the transfer of antibiotic resistances (AR) via the food chain, limited information exists on this issue in species of Leuconostoc and Weissella, adjunct cultures used as aroma producers in fermented foods. In this work, the minimum inhibitory concentration was determined for 16 antibiotics in 34 strains of dairy origin, belonging to Leuconostoc mesenteroides (18), Leuconostoc citreum (11), Leuconostoc lactis (2), Weissella hellenica (2), and Leuconostoc carnosum (1). Atypical resistances were found for kanamycin (17 strains), tetracycline and chloramphenicol (two strains each), and erythromycin, clindamycin, virginiamycin, ciprofloxacin, and rifampicin (one strain each). Surprisingly, L. mesenteroides subsp. mesenteroides LbE16, showed resistance to four antibiotics, kanamycin, streptomycin, tetracycline and virginiamycin. PCR analysis identified tet(S) as responsible for tetracycline resistance in LbE16, but no gene was detected in a second tetracycline-resistant strain, L. mesenteroides subsp. cremoris LbT16. In Leuconostoc mesenteroides subsp. dextranicum LbE15, erythromycin and clindamycin resistant, an erm(B) gene was amplified. Hybridization experiments proved erm(B) and tet(S) to be associated to a plasmid of â35 kbp and to the chromosome of LbE15 and LbE16, respectively. The complete genome sequence of LbE15 and LbE16 was used to get further insights on the makeup and genetic organization of AR genes. Genome analysis confirmed the presence and location of erm(B) and tet(S), but genes providing tetracycline resistance in LbT16 were again not identified. In the genome of the multi-resistant strain LbE16, genes that might be involved in aminoglycoside (aadE, aphA-3, sat4) and virginiamycin [vat(E)] resistance were further found. The erm(B) gene but not tet(S) was transferred from Leuconostoc to Enterococcus faecalis both under laboratory conditions and in cheese. This study contributes to the characterization of AR in the

Production and application of a rare disaccharide using sucrose phosphorylase from Leuconostoc mesenteroides.

PubMed

Morimoto, Kenji; Yoshihara, Akihide; Furumoto, Toshio; Takata, Goro

2015-06-01

Sucrose phosphorylase (SPase) from Leuconostoc mesenteroides exhibited activity towards eight ketohexoses, which behaved as D-glucosyl acceptors, and Î±-D-glucose-1-phosphate (G1P), which behaved as a donor. All eight of these ketohexoses were subsequently transformed into the corresponding d-glucosyl-ketohexoses. Of the eight ketohexoses evaluated in the current study, d-allulose behaved as the best substrate for SPase, and the resulting d-glucosyl-d-alluloside product was found to be a non-reducing sugar with a specific optical rotation of [Î±]D(20) + 74.36Â°. D-Glucosyl-D-alluloside was identified as Î±-D-glucopyranosyl-(1â2)-Î²-D-allulofuranoside by NMR analysis. D-Glucosyl-D-alluloside exhibited an inhibitory activity towards an invertase from yeast with a Km value of 50 mM, where it behaved as a competitive inhibitor with a Ki value of 9.2 mM. D-Glucosyl-D-alluloside was also successfully produced from sucrose using SPase and D-tagatose 3-epimerase. This process also allowed for the production of G1P from sucrose and d-allulose from D-fructose, which suggested that this method could be used to prepare d-glucosyl-d-alluloside without the need for expensive reagents such as G1P and d-allulose. Copyright Â© 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Lactobacillus and Leuconostoc volatilomes in cheese conditions.

PubMed

PogaÄiÄ, Tomislav; Maillard, Marie-Bernadette; Leclerc, AurÃ©lie; HervÃ©, Christophe; Chuat, Victoria; Valence, Florence; Thierry, Anne

2016-03-01

New strains are desirable to diversify flavour of fermented dairy products. The objective of this study was to evaluate the potential of Leuconostoc spp. and Lactobacillus spp. in the production of aroma compounds by metabolic fingerprints of volatiles. Eighteen strains, including five Lactobacillus species (Lactobacillus fermentum, Lactobacillus helveticus, Lactobacillus paracasei, Lactobacillus rhamnosus, Lactobacillus sakei) and three Leuconostoc species (Leuconostoc citreum, Leuconostoc lactis, and Leuconostoc mesenteroides) were incubated for 5 weeks in a curd-based slurry medium under conditions mimicking cheese ripening. Populations were enumerated and volatile compounds were analysed by headspace trap gas chromatography-mass spectrometry (GC-MS). A metabolomics approach followed by multivariate statistical analysis was applied for data processing and analysis. In total, 12 alcohols, 10 aldehydes, 7 esters, 11 ketones, 5 acids and 2 sulphur compounds were identified. Very large differences in concentration of volatile compounds between the highest producing strains and the control medium were observed in particular for diacetyl, 2-butanol, ethyl acetate, 3-methylbutanol, 3-methylbutanoic acid and 2-methylbutanoic acid. Some of the characterized strains demonstrated an interesting aromatizing potential to be used as adjunct culture.

Functional Properties of Novel Epigallocatechin Gallate Glucosides Synthesized by Using Dextransucrase from Leuconostoc mesenteroides B-1299CB4.

PubMed

Kim, Jiyoun; Nguyen, Thi Thanh Hanh; Kim, Nahyun M; Moon, Young-Hwan; Ha, Jung-Min; Park, Namhyeon; Lee, Dong-Gu; Hwang, Kyeong-Hwan; Park, Jun-Seong; Kim, Doman

2016-12-07

Epigallocatechin gallate (EGCG) is the most abundant catechin found in the leaves of green tea, Camellia sinensis. In this study, novel epigallocatechin gallate-glucocides (EGCG-Gs) were synthesized by using dextransucrase from Leuconostoc mesenteroides B-1299CB4. Response surface methodology was adopted to optimize the conversion of EGCG to EGCG-Gs, resulting in a 91.43% conversion rate of EGCG. Each EGCG-G was purified using a C 18 column. Of nine EGCG-Gs identified by nuclear magnetic resonance analysis, five EGCG-Gs (2 and 4-7) were novel compounds with yields of 2.2-22.6%. The water solubility of the five novel compounds ranged from 229.7 to 1878.5 mM. The 5'-OH group of EGCG-Gs expressed higher antioxidant activities than the 4'-OH group of EGCG-Gs. Furthermore, glucosylation at 7-OH group of EGCG-Gs was found to be responsible for maintaining tyrosinase inhibitory activity and increasing browning-resistant activities.

Proline-Based Cyclic Dipeptides from Korean Fermented Vegetable Kimchi and from Leuconostoc mesenteroides LBP-K06 Have Activities against Multidrug-Resistant Bacteria.

PubMed

Liu, Rui; Kim, Andrew H; Kwak, Min-Kyu; Kang, Sa-Ouk

2017-01-01

Lactobacillus plantarum and Leuconostoc mesenteroides play a prominent role as functional starters and predominant isolates in the production of various types of antimicrobial compound-containing fermented foods, especially including kimchi. In the case of the bioactive cyclic dipeptides, their racemic diastereomers inhibitory to bacteria and fungi have been suggested to come solely from Lactobacillus spp. of these strains. We previously demonstrated the antifungal and antiviral activities of proline-based cyclic dipeptides, which were fractionated from culture filtrates of Lb. plantarum LBP-K10 originated from kimchi. However, cyclic dipeptides have not been identified in the filtrates, either from cultures or fermented subject matter, driven by Ln. mesenteroides , which have been widely used as starter cultures for kimchi fermentation. Most importantly, the experimental verification of cyclic dipeptide-content changes during kimchi fermentation have also not been elucidated. Herein, the antibacterial fractions, including cyclo(Leu-Pro) and cyclo(Phe-Pro), from Ln. mesenteroides LBP-K06 culture filtrates, which exhibited a typical chromatographic retention behavior (t R ), were identified by using semi-preparative high-performance liquid chromatography and gas chromatography-mass spectrometry. Based on this finding, the proline-based cyclic dipeptides, including cyclo(Ser-Pro), cyclo(Tyr-Pro), and cyclo(Leu-Pro), were additionally identified in the filtrates only when fermenting Chinese cabbage produced with Ln. mesenteroides LBP-K06 starter cultures. The detection and isolation of cyclic dipeptides solely in controlled fermented cabbage were conducted under the control of fermentation-process parameters concomitantly with strong CDP selectivity by using a two-consecutive-purification strategy. Interestingly, cyclic dipeptides in the filtrates, when using this strain as a starter, increased with fermentation time. However, no cyclic dipeptides were observed in the

Lime application for the efficient production of nutraceutical glucooligosaccharides from Leuconostoc mesenteroides NRRL B-742 (ATCC13146).

PubMed

Moon, Young Hwan; Madsen, Lee; Chung, Chang-Ho; Kim, Doman; Day, Donal F

2015-02-01

We have previously demonstrated the production of glucooligosaccharides via a fermentation of sucrose with Leuconostoc mesenteroides NRRL B-742 using sodium hydroxide (NaOH) to control the pH. Because NaOH is expensive, we sought to minimize the cost of our process by substituting hydrated lime and saccharate of lime (lime sucrate) in its place. The yield of glucooligosaccharides using either 5 % lime (41.4 Â± 0.5 g/100 g) or 5 % lime sucrate (40.0 Â± 1.4 g/100 g) were both similar to the NaOH control (42.4 Â± 1.5 g/100 g). Based on this, it appears that the cost associated with pH control in our process can be reduced by a factor of approximately 2.4 using lime instead of NaOH. Because our chromatographic stage is based on a Ca(2+)-form resin to separate glucooligosaccharides, the use of lime not only negates the need for costly de-salting via ion-exchange (elimination of two ion-exchange sections) prior to separation, but also greatly reduces the resin regeneration cost.

Selection of Leuconostoc strains isolated from artisanal Serrano Catarinense cheese for use as adjuncts in cheese manufacture.

PubMed

Seixas, Felipe Nael; Rios, Edson AntÃ´nio; Martinez de Oliveira, AndrÃ© Luiz; Beloti, Vanerli; Poveda, Justa Maria

2018-08-01

Serrano Catarinense cheese is a raw bovine milk cheese produced in the region of Santa Catarina, Brazil. Twelve representative strains of Leuconostoc isolated from 20 samples of this artisanal cheese were selected and submitted for evaluation of the acidifying, proteolytic, autolytic, aminopeptidase and lipolytic activities, NaCl and acid resistance, production of dextran and biogenic amines and antimicrobial activity. The aim was to genetically and technologically characterize the Leuconostoc strains in order to use them in mixed starter cultures for cheese manufacture. Leuconostoc mesenteroides subsp. mesenteroides was the species that accounted for the largest proportion of isolates of Leuconostoc genus. Two leuconostoc isolates stood out in the acidifying activity, with reduction in pH of 1.12 and 1.04âunits. The isolates showed low proteolytic and autolytic activity. Most of the isolates were dextran producers, presented good resistance to the salt and pH conditions of the cheese and showed antimicrobial activity against cheese pathogen bacteria, and none of them produced biogenic amines. These results allowed the selection of five strains (UEL 04, UEL 12, UEL 18, UEL 21 and UEL 28) as good candidates for use as adjunct cultures for cheese manufacture. Â© 2018 Society of Chemical Industry. Â© 2018 Society of Chemical Industry.

Exploitation of Leuconostoc mesenteroides strains to improve shelf life, rheological, sensory and functional features of prickly pear (Opuntia ficus-indica L.) fruit puree.

PubMed

Di Cagno, Raffaella; Filannino, Pasquale; Vincentini, Olimpia; Lanera, Alessia; Cavoski, Ivana; Gobbetti, Marco

2016-10-01

Strains of Leuconostoc mesenteroides were identified from raw prickly pear (Opuntia ficus-indica L.). Five autochthonous strains were selected based on the kinetics of growth and acidification on prickly pear fruit juice, and the capacity to synthesize exo-polysaccharides. All selected Leuc. mesenteroides strains showed an inÂ vitro mucilage-degrading capability. A protocol for processing and storage of fermented prickly pear fruit puree (FP) was set up. Unstarted FP and chemically acidified FP were used as the controls. Starters grew and remained viable at elevated cell numbers during 21 days of storage at 4Â Â°C. Contaminating Enterobacteriaceae and yeasts were found only in the controls. Viscosity and serum separation distinguished started FP compared to the controls. Colour parameters, browning index, sensory attributes, antimicrobial activity, vitamin C and betalains levels were positively affected by lactic acid fermentation. Increase of free radical scavenging activity in ethyl acetate soluble extract suggested an effect of selected strains on phenolic profiles. Started FP markedly inhibited the inflammatory status of Caco-2/TC7 cells, and also contributed to maintaining the integrity of tight junctions. Started FP scavenged the reactive oxygen species generated by H2O2 on Caco-2Â cells. All selected strain variously affected the immunomodulatory activity towards anti- and pro-inflammatory cytokines. Copyright Â© 2016 Elsevier Ltd. All rights reserved.

Leuconostoc strains isolated from dairy products: Response against food stress conditions.

PubMed

D'Angelo, Luisa; Cicotello, JoaquÃ­n; Zago, Miriam; Guglielmotti, Daniela; Quiberoni, Andrea; SuÃ¡rez, Viviana

2017-09-01

A systematic study about the intrinsic resistance of 29 strains (26 autochthonous and 3 commercial ones), belonging to Leuconostoc genus, against diverse stress factors (thermal, acidic, alkaline, osmotic and oxidative) commonly present at industrial or conservation processes were evaluated. Exhaustive result processing was made by applying one-way ANOVA, Student's test (t), multivariate analysis by Principal Component Analysis (PCA) and Matrix Hierarchical Cluster Analysis. In addition, heat adaptation on 4 strains carefully selected based on previous data analysis was assayed. The strains revealed wide diversity of resistance to stress factors and, in general, a clear relationship between resistance and Leuconostoc species was established. In this sense, the highest resistance was shown by Leuconostoc lactis followed by Leuconostoc mesenteroides strains, while Leuconostoc pseudomesenteroides and Leuconostoc citreum strains revealed the lowest resistance to the stress factors applied. Heat adaptation improved thermal cell survival and resulted in a cross-resistance against the acidic factor. However, all adapted cells showed diminished their oxidative resistance. According to our knowledge, this is the first study regarding response of Leuconostoc strains against technological stress factors and could establish the basis for the selection of "more robust" strains and propose the possibility of improving their performance during industrial processes. Copyright Â© 2017 Elsevier Ltd. All rights reserved.

Optimization of dextran production by Leuconostoc mesenteroides NRRL B-512 using cheap and local sources of carbohydrate and nitrogen.

PubMed

Behravan, Javad; Bazzaz, B Seddigheh Fazly; Salimi, Zohreh

2003-12-01

Using pure components for the fermentation medium in dextran production imposes high costs on the industry. In the present study, the economic production of dextran using local and cheap sources of carbohydrate and nitrogen was investigated. Different concentrations of molasses and wheat-bran extract, after filtration, steam sterilization and pH adjustment, were inoculated with a fresh suspension of Leuconostoc mesenteroides. Cultures were incubated, and then diluted with an equal volume of ethanol. The bacteria were pelleted, and an aliquot of the supernatant was diluted with ethanol and dextran was precipitated. The supernatant was removed and the precipitate was dissolved in a minimal volume of water. Activated charcoal was added and the solution was boiled. The solution was filtered and protein impurities removed by 2-methylbutan-2-ol/chloroform extraction. Dextran was again precipitated with cold ethanol as described above, and the precipitate was dried in a desiccator. Optimum conditions and composition of culture media for dextran production using sugar-beet molasses and wheat bran were determined. The best results were obtained when 20% (w/v) molasses and 15% (w/v) wheat bran were used. The optimal initial pH for dextran production was 7.5.

Production of a bacteriocin-like inhibitory substance by Leuconostoc mesenteroides subsp. dextranicum 213M0 isolated from Mongolian fermented mare milk, airag.

PubMed

Arakawa, Kensuke; Yoshida, Saki; Aikawa, Hiroki; Hano, Chihiro; Bolormaa, Tsognemekh; Burenjargal, Sedkhuu; Miyamoto, Taku

2016-03-01

Strain 213M0 was selected with productivity of a bacteriocin-like inhibitory substance (BLIS) among 235 strains of lactic acid bacteria (LAB) isolated from Mongolian fermented milk 'airag'. Strain 213M0 was species-identified as Leuconostoc mesenteroides subsp. dextranicum by morphological observation, carbohydrate fermentation profiling and sequencing the 16S rRNA gene. Incubation temperature proper to produce the BLIS was 25Â°C rather than 30 and 37Â°C, and the production actively proceeded during the exponential growth phase of the producer cells. Antibacterial effect of BLIS 213M0 was limited to all nine strains of Listeria sp. bacteria and seven strains of LAB cocci among 53 tested strains, which corresponds to a typical feature of the class IIa pediocin-like bacteriocins. BLIS 213M0 was not inactivated in every broad pH range solution (pH 2.0-11.0), and was stable against storage at 25Â°C for 1 week and heating at 121Â°C for 15 min under pH 4.5. Peptide frame of BLIS 213M0 was confirmed by inactivation with some peptidases, and then its molecular weight was estimated to be 2.6-3.0 kDa using an in situ activity assay following sodium dodecyl sulfate polyacrylamide gel electrophoresis. The estimated size was different from the other Leuconostoc bacteriocins already reported. These results suggest that BLIS 213M0 would be a novel listericidal bacteriocin. Â© 2015 Japanese Society of Animal Science.

Mode of action of leucocin K7 produced by Leuconostoc mesenteroides K7 against Listeria monocytogenes and its potential in milk preservation.

PubMed

Shi, Feng; Wang, Yanwei; Li, Yongfu; Wang, Xiaoyuan

2016-09-01

To investigate the mode of action of leucocin K7 against Listeria monocytogenes and to assess its inhibitory effect on Lis. monocytogenes in refrigerated milk. A bacteriocin-producing strain, Leuconostoc mesenteroides K7, was isolated from a fermented pickle. The bacteriocin, leucocin K7, exhibited antagonistic activity against Lis. monocytogenes with an MIC of 28Â Âµg/ml. It was sensitive to proteaseS and displayed good thermal stability and broad active pH range. Leucocin K7 had no effect on the efflux of ATP from Lis. monocytogenes but triggered the efflux of K(+) and the intracellular hydrolysis of ATP. It also dissipated the transmembrane electrical potential completely and transmembrane pH gradient partially. It 80 AU/ml inhibited the growth of Lis. monocytogenes by 2.3-3.9 log units in milk; when combined with glycine (5Â mg/ml), it completely eliminated viable Lis. monocytogenes over 7Â days Leucocin K7 shows different mode of action from nisin and may have potential application in milk preservation.

Synthesis and characterization of a potential prebiotic trisaccharide from cheese whey permeate and sucrose by Leuconostoc mesenteroides dextransucrase.

PubMed

DÃ­ez-Municio, Marina; Montilla, Antonia; Jimeno, M Luisa; Corzo, Nieves; Olano, AgustÃ­n; Moreno, F Javier

2012-02-29

The production of new bioactive oligosaccharides is currently garnering much attention for their potential use as functional ingredients. This work addresses the enzymatic synthesis and NMR structural characterization of 2-Î±-D-glucopyranosyl-lactose derived from sucrose:lactose and sucrose:cheese whey permeate mixtures by using a Leuconostoc mesenteroides B-512F dextransucrase. The effect of synthesis conditions, including concentration of substrates, molar ratio of donor/acceptor, enzyme concentration, reaction time, and temperature, on the formation of transfer products is evaluated. Results indicated that cheese whey permeate is a suitable material for the synthesis of 2-Î±-D-glucopyranosyl-lactose, giving rise to yields around 50% (in weight respect to the initial amount of lactose) under the optimum reaction conditions. According to its structure, this trisaccharide is an excellent candidate for a new prebiotic ingredient, due to the reported high resistance of Î±-(1â2) linkages to the digestive enzymes in humans and animals, as well as to its potential selective stimulation of beneficial bacteria in the large intestine mainly attributed to the two linked glucose units located at the reducing end that reflects the disaccharide kojibiose (2-Î±-D-glucopyranosyl-D-glucose). These findings could contribute to broadening the use of important agricultural raw materials, such as sucrose or cheese whey permeates, as renewable substrates for enzymatic synthesis of oligosaccharides of nutritional interest.

Potential use of lactic acid bacteria Leuconostoc mesenteroides as a probiotic for the removal of Pb(II) toxicity.

PubMed

Yi, Young-Joo; Lim, Jeong-Muk; Gu, Suna; Lee, Wan-Kyu; Oh, Eunyoung; Lee, Sang-Myeong; Oh, Byung-Taek

2017-04-01

It has been demonstrated that certain lactic acid bacteria (LAB) can sequester metal ions by binding them to their surfaces. In the present study, lead (Pb)-resistant LAB were isolated from kimchi, a Korean fermented food. A total of 96 different LAB strains were isolated, and 52 strains showed lead resistance. Among them, an LAB strain-96 (L-96) identified as Leuconostoc mesenteroides showed remarkable Pb resistance and removal capacity. The maximum adsorption capacity of this strain calculated using the Langmuir isotherm was 60.6 mg Pb/g. In an in vivo experiment, young male mice were provided with water (A), Pb-water (B), or Pb-water+ L-96 (C) during puberty. Lower glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) levels in Pb-exposed male mice that received strain L-96 as a probiotic were suggestive of reduced hepatotoxicity. Moreover, feces from mice treated with L-96 contained more Pb than feces from untreated mice. Increased Pb elimination likely reduced internal accumulation, and this hypothesis was supported by significantly lower Pb concentrations in kidneys and testes of the mice treated with strain L-96. The motility and ATP content of epididymal spermatozoa were partially restored if strain L-96 was administered. In conclusion, isolated L-96 LAB had lead-biosorption activity and efficiently detoxified lead-poisoned male mice, resulting in recovering male reproductive function. These results suggest the potential use of LAB as a probiotic to protect humans from the adverse effects of Pb exposure.

ATM CMG/EPEA

NASA Technical Reports Server (NTRS)

Abramowitz, R.; Kovek, J.; Teimer, W.; Haddad, S. P.

1975-01-01

The Apollo Telescope mount double gimballed control moment gyro ATM CMG is described. Photographs of the CMG and its subassemblies are presented along with a functional block diagram of the CMG subsystem. Analog processing electronics for ATM vehicle pointing control and ATM experiment package pointing control are also described.

Leuconostoc bacteriophages from blue cheese manufacture: long-term survival, resistance to thermal treatments, high pressure homogenization and chemical biocides of industrial application.

PubMed

Pujato, Silvina A; Guglielmotti, Daniela M; Ackermann, Hans-W; Patrignani, Francesca; Lanciotti, Rosalba; Reinheimer, Jorge A; Quiberoni, Andrea

2014-05-02

Nine Leuconostoc mesenteroides phages were isolated during blue cheese manufacture yielding faulty products with reduced eye formation. Their morphologies, restriction profiles, host ranges and long-term survival rates (25Â°C, 8Â°C, -20Â°C and -80Â°C) were analysed. Based on restriction analysis, six of them were further examined regarding resistance to physical (heat and high pressure homogenization, HPH) and chemical treatments (ethanol, sodium hypochlorite, peracetic acid, biocides A, C, E and F). According to their morphology, L. mesenteroides phages studied in the present work belonged to the Caudovirales order and Siphoviridae family. Six distinct restriction patterns were obtained with EcoRV, HindIII, ClaI and XhoI enzymes, revealing interesting phage diversity in the dairy environment. No significant reductions in phage counts were observed after ten months of storage at -20Â°C and -80Â°C, while slightly and moderate decrease in phage numbers were noticed at 8Â°C and 25Â°C, respectively. The phages subjected to heat treatments generally showed high resistance at 63Â°C and moderate resistance at 72Â°C. However, 80Â°C for 30 min and 90Â°C for 2 min led to complete inactivation of viral particles. In general, the best ethanol concentration tested was 75%, as complete inactivation for most Leuconostoc phages within 30 min of incubation was achieved. Peracetic acid, and biocides A, C, E and F were highly effective when used at the same or at a moderately lower concentration as recommended by the producer. Usually, moderate or high concentrations (600-1,600 ppm) of sodium hypochlorite were necessary to completely inactivate phage particles. Leuconostoc phages were partially inactivated by HPH treatments as remaining viral particles were found even after 8 passes at 100 MPa. This is the first report of L. mesenteroides phages isolated from an Argentinean dairy cheese plant. The results of this work could be useful for establishing the most effective physical and

ATM CMG bearing failure analysis

NASA Technical Reports Server (NTRS)

1975-01-01

The cause or causes for the failure of ATM CMG S/N 5 (Skylab 1) and the anomalies associated with ATM CMG S/N 6 (Skylab 2) were investigated. Skylab telemetry data were reviewed and presented in the form of parameter distributions. The theory that the problems were caused by marginal bearing lubrication was studied along with the effects of orbital conditions on lubricants. Bearing tests were performed to investigate the effect of lubricant or lack of lubricant in the ATM CMG bearings and the dispersion and migration of the lubricant. The vacuum and weightless conditions of space were simulated in the bearing tests. Analysis of the results of the tests conducted points to inadequate lubrication as the predominant factor causing the failure of ATM CMG S/N 5 (Skylab 1) and the anomalies associated with ATM CMG S/N 6 (Skylab 2).

Isolation and Identification of Lactic Acid Bacteria Isolated from a Traditional Jeotgal Product in Korea

NASA Astrophysics Data System (ADS)

Cho, Gyu Sung; Do, Hyung Ki

2006-06-01

Seventeen lactic acid bacterial strains (LAB) were isolated using MRS agar medium from Jeotgal, a Korean fermented food, purchased at the Jukdo market of Pohang. To identify the strains isolated, they were tested by examining their cell morphologies, gram-staining, catalase activity, arginine hydrolase activity, D-L lactate form and carbohydrate fermentation. According to the phenotypic characteristics, three strains were tent atively identified as Lactobacillus spp., ten were Enterococcus spp. (or Streptococcus spp., or Pediococcus spp.) and the rest were Leuconostoc spp. (or Weissella spp.). Five strains among 17 were chosen by preliminary bacteriocin activity test. Four bacterial strains which inhibited both indicator microorganisms were identified by 16S rRNA sequencing. The results are as follows; Leuconostoc mesenteroides (HK 4), Leuconostoc mesenteroides (HK 5), Leuconostoc mesenteroides(HK 11), Streptococcus salivarius(HK 8). In order to check LAB which are showing a high survival rate in gut, we investigated three strains inhibiting both indicator microorganisms in artificial gastric acid and bile juice -all except HK8. The three strains mentioned above grew in extreme low acid conditions.

Gimbal-Angle Vectors of the Nonredundant CMG Cluster

NASA Astrophysics Data System (ADS)

Lee, Donghun; Bang, Hyochoong

2018-05-01

This paper deals with the method using the preferred gimbal angles of a control moment gyro (CMG) cluster for controlling spacecraft attitude. To apply the method to the nonredundant CMG cluster, analytical gimbal-angle solutions for the zero angular momentum state are derived, and the gimbal-angle vectors for the nonzero angular momentum states are studied by a numerical method. It will be shown that the number of the gimbal-angle vectors is determined from the given skew angle and the angular momentum state of the CMG cluster. Through numerical examples, it is shown that the method using the preferred gimbal-angle is an efficient approach to avoid internal singularities for the nonredundant CMG cluster.

Detection of Lactobacillus, Pediococcus, Leuconostoc, and Weissella Species in Human Feces by Using Group-Specific PCR Primers and Denaturing Gradient Gel Electrophoresis

PubMed Central

Walter, Jens; Hertel, Christian; Tannock, Gerald W.; Lis, Claudia M.; Munro, Karen; Hammes, Walter P.

2001-01-01

Denaturing gradient gel electrophoresis (DGGE) of DNA fragments generated by PCR with 16S ribosomal DNA-targeted group-specific primers was used to detect lactic acid bacteria (LAB) of the genera Lactobacillus, Pediococcus, Leuconostoc, and Weissella in human feces. Analysis of fecal samples of four subjects revealed individual profiles of DNA fragments originating not only from species that have been described as intestinal inhabitants but also from characteristically food-associated bacteria such as Lactobacillus sakei, Lactobacillus curvatus, Leuconostoc mesenteroides, and Pediococcus pentosaceus. Comparison of PCR-DGGE results with those of bacteriological culture showed that the food-associated species could not be cultured from the fecal samples by plating on Rogosa agar. On the other hand, all of the LAB species cultured from feces were detected in the DGGE profile. We also detected changes in the types of LAB present in human feces during consumption of a milk product containing the probiotic strain Lactobacillus rhamnosus DR20. The analysis of fecal samples from two subjects taken before, during, and after administration of the probiotic revealed that L. rhamnosus was detectable by PCR-DGGE during the test period in the feces of both subjects, whereas it was detectable by culture in only one of the subjects. PMID:11375166

CMG2 Expression Is an Independent Prognostic Factor for Soft Tissue Sarcoma Patients

PubMed Central

Wedler, Alice; Rot, Swetlana; KeÃler, Jacqueline; Kehlen, Astrid; Holzhausen, Hans-JÃ¼rgen; Bache, Matthias; WÃ¼rl, Peter; Kappler, Matthias

2017-01-01

The capillary morphogenesis gene 2 (CMG2), also known as the anthrax toxin receptor 2 (ANTXR2), is a transmembrane protein putatively involved in extracellular matrix (ECM) adhesion and tissue remodeling. CMG2 promotes endothelial cell proliferation and exhibits angiogenic properties. Its downregulation is associated with a worsened survival of breast carcinoma patients. Aim of this study was to analyze the CMG2 mRNA and protein expression in soft tissue sarcoma and their association with patient outcome. CMG2 mRNA was measured in 121 tumor samples of soft tissue sarcoma patients using quantitative real-time PCR. CMG2 protein was evaluated in 52 tumor samples by ELISA. CMG2 mRNA was significantly correlated with the corresponding CMG2 protein expression (rs = 0.31; p = 0.027). CMG2 mRNA expression was associated with the mRNA expressions of several ECM and tissue remodeling enzymes, among them CD26 and components of the uPA system. Low CMG2 mRNA expression was correlated with a worsened patientsâ disease-specific survival in Kaplan-Meier analyses (mean patient survival was 25 vs. 96 months; p = 0.013), especially in high-stage tumors. A decreased CMG2 expression is a negative prognostic factor for soft tissue sarcoma patients. CMG2 may be an interesting candidate gene for the further exploration of soft tissue sarcoma genesis and progression. PMID:29215551

CMG2 Expression Is an Independent Prognostic Factor for Soft Tissue Sarcoma Patients.

PubMed

Greither, Thomas; Wedler, Alice; Rot, Swetlana; KeÃler, Jacqueline; Kehlen, Astrid; Holzhausen, Hans-JÃ¼rgen; Bache, Matthias; WÃ¼rl, Peter; Taubert, Helge; Kappler, Matthias

2017-12-07

The capillary morphogenesis gene 2 (CMG2), also known as the anthrax toxin receptor 2 (ANTXR2), is a transmembrane protein putatively involved in extracellular matrix (ECM) adhesion and tissue remodeling. CMG2 promotes endothelial cell proliferation and exhibits angiogenic properties. Its downregulation is associated with a worsened survival of breast carcinoma patients. Aim of this study was to analyze the CMG2 mRNA and protein expression in soft tissue sarcoma and their association with patient outcome. CMG2 mRNA was measured in 121 tumor samples of soft tissue sarcoma patients using quantitative real-time PCR. CMG2 protein was evaluated in 52 tumor samples by ELISA. CMG2 mRNA was significantly correlated with the corresponding CMG2 protein expression (r s = 0.31; p = 0.027). CMG2 mRNA expression was associated with the mRNA expressions of several ECM and tissue remodeling enzymes, among them CD26 and components of the uPA system. Low CMG2 mRNA expression was correlated with a worsened patients' disease-specific survival in Kaplan-Meier analyses (mean patient survival was 25 vs. 96 months; p = 0.013), especially in high-stage tumors. A decreased CMG2 expression is a negative prognostic factor for soft tissue sarcoma patients. CMG2 may be an interesting candidate gene for the further exploration of soft tissue sarcoma genesis and progression.

CMG-Augmented Control of a Hovering VTOL Platform

NASA Technical Reports Server (NTRS)

Lim, K. B.; Moerder, D. D.

2007-01-01

This paper describes how Control Moment Gyroscopes (CMGs) can be used for stability augmentation to a thrust vectoring system for a generic Vertical Take-Off and Landing platform. The response characteristics of the platform which uses only thrust vectoring and a second configuration which includes a single-gimbal CMG array are simulated and compared for hovering flight while subject to severe air turbulence. Simulation results demonstrate the effectiveness of a CMG array in its ability to significantly reduce the agility requirement on the thrust vectoring system. Albeit simplifying physical assumptions on a generic CMG configuration, the numerical results also suggest that reasonably sized CMGs will likely be sufficient for a small hovering vehicle.

Proposed CMG momentum management scheme for space station

NASA Technical Reports Server (NTRS)

Bishop, L. R.; Bishop, R. H.; Lindsay, K. L.

1987-01-01

A discrete control moment gyro (CMG) momentum management scheme (MMS) applicable to spacecraft with principal axes misalignments, such as the proposed NASA dual keel space station, is presented in this paper. The objective of the MMS is to minmize CMG angular momentum storage requirements for maintaining the space station near local vertical in the presence of environmental disturbances. It utilizes available environmental disturbances, namely gravity gradient torques, to minimize CMG momentum storage. The MMS is executed once per orbit and generates a commanded torque equilibrium attitude (TEA) time history which consists of a yaw, pitch and roll angle command profile. Although the algorithm is called only once per orbit to compute the TEA profile, the space station will maneuver several discrete times each orbit.

Biodiversity of lactic acid bacteria in Moroccan soft white cheese (Jben).

PubMed

Ouadghiri, Mouna; Amar, Mohamed; Vancanneyt, Marc; Swings, Jean

2005-10-15

The bacterial diversity occurring in traditional Moroccan soft white cheese, produced in eight different regions in Morocco, was studied. A total of 164 lactic acid bacteria were isolated, purified and identified by whole-cell protein fingerprinting and rep-PCR genomic fingerprinting. The majority of the strains belonged to the genera Lactobacillus, Lactococcus, Leuconostoc and Enterococcus. Sixteen species were identified: Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus paracasei, Lactobacillus brevis, Lactobacillus buchneri, Lactococcus lactis, Lactococcus garvieae, Lactococcus raffinolactis, Leuconostoc pseudomesenteroides, Leuconostoc mesenteroides, Leuconostoc citreum, Eterococcus durans, Enterococcus faecalis, Enterococcus faecium, Enterococcus saccharominimus and Streptococcus sp.

Genotypic and technological characterization of Leuconostoc isolates to be used as adjunct starters in Manchego cheese manufacture.

PubMed

Nieto-Arribas, Pedro; SeseÃ±a, Susana; Poveda, Justa M; Palop, Llanos; Cabezas, Lourdes

2010-02-01

Twenty-seven Leuconostoc (Ln.) isolates from Manchego cheese were characterized by phenotypic and genotypic methods, and their technological abilities studied in order to test their potential use as dairy starter components. While phenotypic diversity was evaluated by studying the biochemical characteristics of technological interest (i.e. acidifying and aminopeptidase activities), genotypic diversity was evidenced by using Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR). Additional technological abilities such as lipolytic, proteolytic and autolytic activities, salt and pH tolerance and production of dextran, flavour compounds and biogenic amines, were investigated. The marked differences among strains reflected the existing biodiversity in naturally fermented products. After statistically evaluating their performance, strains C0W2, belonging to Ln. lactis, and C16W5 and N2W5, belonging to Ln. mesenteroides subsp. dextranicum, revealed the best properties to be used in mixed dairy starter cultures. This study evidences the fact that natural environments can be considered as a proper source of useful strains, for the dairy industry.

21 CFR 186.1275 - Dextrans.

Code of Federal Regulations, 2014 CFR

2014-04-01

... by bacterial fermentation of sucrose. Commercially available dextrans are synthesized from sucrose by Leuconostoc mesenteroides strain NRRL B-512(F). Partial depolymerization and purification of the fermented...

View of the new CMG during Expedition 15/STS-118 EVA 2

NASA Image and Video Library

2007-08-13

ISS015-E-22366 (13 Aug. 2007) --- A close-up view of the new control moment gyroscope (CMG) photographed by a crewmember during the mission's second planned session of extravehicular activity (EVA). During the spacewalk, Canadian Space Agency's astronaut Dave Williams (out of frame) and astronaut Rick Mastracchio (out of frame), both STS-118 mission specialists, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior before it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

Effect of Initial Headspace O2 Level on the Growth and Volatile Metabolite Production of Leuconostoc Mesenteriodes and the Microbial and Se