• Journal of Microbiology and Biotechnology
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• v.6 no.4
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• pp.270-277
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• 1996

A bacteriocin-producing strain, DU-0608, was isolated from Kimchi and identified as Leuconostoc mesenteroides subsp. mesenteroides. The bacteriocin from isolate was inhibitory against Listeria monocytogenes, Micrococcus luteus and several strains of lactic acid bacteria. The bacteriocin was inactivated by pepsin, trypsin, $\alpha$-chymotrypsin, protease, $\alpha$-amylase and lipase, but not by catalase or by heating at $100^{\circ}C$ for 60 min. The molecular weight of the bacteriocin was estimated approximately 6 kDa. The inhibitory effect was bactericidal and rapid. Following treatment with isolate bacteriocin, cells of indicator strain (Lactobacillus sake JCM 1157) were damaged at the end regions of the cell wall, whereas the cells treated with nisin were damaged at many places around the cell wall.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.153-156
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• 2003

The MRS medium is widely used as an optimized medium for the growth of Lactobacillus spp. and also used for the growth of Leuconostoc spp. Leuconostoc mesenteroides shows quite different physicochemical properties compared to Lactobacilli spp. and it is one of the major strain of kimchi fermenting microorganisms with its usefulness in our traditional foods and availability in biotechnology in the future, specifically tailor-made medium is necessary for the growth of Leuconostoc mesenteroides. Sequential experimental designs (Plackett-Burman, fractional factorial, steepest ascent, central composite design and response surface methodology) were introduced to optimize and improve the Leuconostoc medium. Fifteen medium ingredients were investigated and fructose, sodium acetate and ammonium citrate were determined to give a critical and positive effect for cell-growth. The yield of biomass using the optimal medium was improved more than that of the MRS medium and the result of fed-batch culture showed the capability of the improvement in cell mass similar to the E.coli system.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.350-359
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• 1997

The changes in pH, acid contents and microbial counts were investigated during fermentation of Baikkimchi, a kind of Kimchi without red pepper, and the major microbial groups were also isolated and identified. Immediately after the preparation of Baikkimchi(pH 6.15, acid contents 0.03%), its major microbial group was Gram negative rods, and was composed of Pseudomonas(55%), Enterobacter(40%) and Erwinia(5%). After 2 days of fermentation at 15$^{\circ}C$, the most predominant microbial group was changed to lactic acid bacteria. Lactic acid bacteria showed 1st, 2nd and 3rd stationary phase on its growth curve in 4, 12 and 50 days of fermentation, respectively. At the 2nd stationary phase of lactic acid bacteria(pH 3.51, acid contents 0.59%), the group was composed of Lactobacillus bavaricus(55%), Leuconostoc mesenteroides subsp. mesenteroides(42.5%) and Leuconostoc paramesenteroides(2.5%), while at the 3rd stationary phase(pH 3.40, acid contents 1.10%), that was Lactobacillus plantarum(65%) and Lactobacillus brevis(35%). The physiological and biochemical characteristics identified as Leuconostoc mesenteroides subsp. mesenteroides, Leuconostoc paramesenteroides, Lactobacillus plantarum and Lactobacillus brevis showed good agreement with the current taxonomic system, but those identified as Lactobacillus bavaricus showed some disagreements. The number of yeast was decreased wit the increase in the number of lactic acid bacteria. Yeast showed stationary phase in 30 days between the 2nd and 3rd stationary phase of lactic acid bacteria, and the group was composed of only gunus Saccharomyces.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.325-329
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• 2006

Leuconostoc mesenteroides B-742 fermentations with maltose as an acceptor were tested for glucooligosaccharides and mannitol co-production. Leuconostoc oligosaccharides were produced that were oligomers with a size range of DP 2 to 7 and were primarily DP 3, 4, 5, and 6, containing mainly ${\alpha}-1,4$ and ${\alpha}-1,6$ linkages. Maltose was linked to the reducing end of the isomaltosyl residues. The $Ca^{2+}$ form of cation-exchange column could separate glucooligosaccharides from byproducts.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1180-1185
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• 2009

This study was aimed to investigate the effect of glycine supplementation on the growth of Leuconostoc mesenteroides and Lactobacillus plantarum during kimchi fermentation. As preliminary experiment, the effect of supplementation of glycine (0-2.0%, w/v) to MRS medium on the growth of Leuc. mesenteroides and L. plantarum was evaluated. At 2.0% glycine in the MRS medium, cell growth rate was inhibited by 79% for L. plantarum and 27% for Leuc. mesenteroides. Subsequently, different concentrations of glycine (0, 0.5, and 2.0%, w/v) were applied for kimchi fermentation for 21 days, at $5^{\circ}C$. At day 14, the pH and titratable acidity (TA) of kimchi supplemented with 2.0% glycine were 4.83 and 0.38%, respectively, whilst the control kimchi had a pH of 4.49 and TA of 0.44%, respectively. The ratio of Leuconostoc/ Lactobacillus in kimchi increased as the concentration of glycine increased. The results show that the presence of glycine affected the growth of the 2 lactic acid bacteria, particularly of L. plantarum.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.461-471
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• 1995

The heterofermentative Leuconostoc mesenteroides, which is propagated from the initial to the intermediate stage of Kimchi fermentation, produces organic acids and carbon dioxide to impart refreshment, weak acid taste to Kimchi. But owing to lactic acid production by the homofermentative Lactobacillus Plantarum, Kimchi finally reaches its acidified state. So, Leu. mesenteroides was isolated from Kimchi and identified and was improved by mutation for carbon dioxide production at low pH, and for the high total acceptability. We tested with a wild-type strain K-1 and its improved mutant strain M-10 of Leu. mesenteroides. The wild-type strain K-1 could grow in pH 4.2 at 30$\circ$C or 20$\circ$C, and in pH 5.0 at 10$\circ$C. But the mutant strain M-10 could grow in pH 3.3 at 10$\circ$C. In the respect of total acceptability, mutant strain M-10 inoculated Kimchi was ever better than any others. Mutant M-10 inoculated Kimchi prolonged the optimum ripening period of Kimchi up to two times as compared with the control group.

• Microbiology and Biotechnology Letters
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• v.36 no.3
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• pp.233-239
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• 2008

A new approach to the solubilization of excess activated sludge by the inoculation of lactic acid bacteria was studied to reduce the amount of sludge produced in the activated sludge treatment process. Aerobic microorganism in sludge was lysed in anaerobic condition and the cytoplasmic substance eluted was utilized as a carbon source by lactic acid bacteria. On the basis of sludge solubilization efficiency, Lactobacillus brevis and Leuconostoc mesenteroides subsp mesenteroides were selected the best candidates among five kinds of Lactobacillus sp. and seven kinds of Leuconostoc sp. The sludge solubilization efficiency by heterofermentative lactic acid bacteria was more efficient than that of homofermentative bacteria. Initial value of soluble COD (sCOD) was 1050 mg/L at the initial inoculation time increased to 3070 mg/L (192% solubilization) at 96 h of the incubation time. The inoculation of lactobacillus brevis to the sludge resulted in 2824% increase in sCOD value after 96 h of incubation than the control experiment. Leuconostoc mesenteroides subsp mesenteroides showed 152% increase of solubilization and 30% increase of S-COD/T-COD on 96 h of incubation time. Considering the increase of S-COD by the inoculation of Leuconostoc sp. on 24 h, 10% inoculation of lactic acid bacteria to the sludge was most effective.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.373-378
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• 1998

This study was performed to investigate antimicrobial effects and their actions of the ethanol extracts of 12 spices against Lactobacillus plantarum and Leuconostoc mesenteroides, which are related to Kimchi fermentation. The cardamon, thyme, and cumin ethanol extracts among 12 spices showed antimicrobial activities against Lac. plantarum, not against Leu. mesenteroides through paper disc method. The growth of Lac. plantarum was inhibited in MRS broth containing each extracts of cardamon (>4%), thyme (>4%) and cumin (>1%). SDS-PAGE and transmission electron micrographs showed that the cell walls and membranes were disrupted and the cytoplasmic components were leaked in strains treated with ethanol extracts.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.311-318
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• 2002

A new bacteriocin producing lactic acid bacteria having antagonistic activity against Lactobacillus plantarum, was isolated from Kimchi. It was identified as Leuconostoc mesenteroides, and designated as Leuconostoc mesenteroides B7. The bacteriocin from Leuconostoc mesenteroides B7 named as bacteriocin B7 was stable in the pH range $2.5{\sim}9.5$. Bacteriocin B7 was active over a wide temperature range from $4^{\circ}C$ to $120^{\circ}C$. It was inactivated by proteinase K, trypsin, ${\alpha}-chymotrypsin$, and protease treatments indicating its proteinous nature. Tricine-SDS-PAGE of the purified bacteriocin B7 showed the presence of a single band, having a molecular mass of about 3,500 dalton. Mixed culture of the producer and the indicator, Lb. plantarum KFRI 464 or Lb. delbruekii KFRI 347, increased production of bacteriocin B7. This result suggested the presence of bacteriocin inducing factor in the indicator strain. The inducing factor was localized in cell debris and intracellular faction of the indicator cell, Lb. plantarum KFRI 464. Treatment of the inducing factor with proteinase K destroyed inducing activity. This result strongly suggested that the inducing factor is a protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.455-460
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• 1998

This study was carried out to investigate antimicrobial activities of ethanol extracts from 12 kinds of spices against Lactobacillus plantarum and Leuconostoc mesenteroides to kimchi fermentation. Lactic acid bacteria were isolated from fermenting kimchi, were identified as Leu. mesenteroides, Lac. sake, Lac. plantarum and Pediococcus pentosaceus. The ethanol extracts of cardamon, thyme and cumin among 12 spices showed antimicrobial activities against Lac. plantarum, while they did not showed the activites against Leu. mesenteroides through paper disc method. In addition, the growth of Lac. plantarum was inhibited in MRS broth containing each of cardamon(>4%), thyme(>4%) an cumin(>1%).