• Food Science and Biotechnology
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• v.17 no.6
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• pp.1391-1395
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• 2008

Leuconostoc citreum HJ-P4 is a strain isolated for kimchi fermentation with its low temperature-adapted growth feature and its high dextransucrase activity. The detailed characteristics of cell growth and dextran sucrase activities were investigated at various environmental conditions such as temperatures, pHs, salts, and raw ingredients. This strain showed almost 2-fold higher maximal cell concentration ($X_{max}$) than that of the type culture Leuconostoc mesenteroides B-512F at $10^{\circ}C$. The $X_{max}$ of the strain was maximum at pH 7 and the cell growth was inhibited by salts in a dose-dependent mode up to 7%. Addition of pepper (<6%), garlic (<10%), and ginger (<2%) in kimchi gave no inhibition effect on the growth of HJ-P4. Dextransucrase synthesized by this strain retained over 80% of its maximum activity at $10^{\circ}C$ showing a comparable cold-adapted feature to its host microbe. This culture can be used as a starter culture in the industrial kimchi production giving desirable functions and predominance at low temperature.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1626-1631
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• 2012

Sixty strains of lactic acid bacteria were isolated from kimchi and used as a starter for fermented tofu. Among the isolated strains, strain KL-6 showed antimicrobial activity against various pathogens, antioxidative activity, and viability in artificial gastric juice and artificial bile acid. The selected strain KL-6 was identified as Pediococcus acidilactici KL-6 by morphological and physiological tests, including Gram staining, catalase test, and 16S rRNA sequencing. The fermentation characteristics of tofu with a kimchi ingredient mixture (Control) consisting of red pepper, garlic, ginger, sugar, salt, jeotgal, and juice of chinese cabbage were compared with those of tofus inoculated with strain KL-6 and the kimchi ingredient mixture (TL) or a pre-fermented kimchi ingredient mixture (TPL) for 24 hr at $37^{\circ}C$. The pH levels of all tested tofu samples decreased after 1 week of fermentation, reaching 3.96 (control), 3.97 (TL), and 4.03 log cfu/g (TPL) after fermentation for 14 weeks at $20^{\circ}C$. Total aerobe content of fermented tofu increased until 2 weeks of fermentation, but decreased steadily thereafter. The number of lactic acid bacteria reached $10^6$ cfu/g after 1 week of fermentation in TL and TPL, whereas it took 2 weeks for the control. The number of lactic acid bacteria in all tested tofu samples reached $10^3$ cfu/g after 14 weeks of fermentation at $20^{\circ}C$. Coliform bacteria were not detected in TL or TPL after 1 week of fermentation. The sensory scores of TL and TPL were higher than that of control in terms of taste, flavor, texture, and overall acceptability. The sensory quality of TPL was the best among all tested fermented tofu samples.

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.392-398
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• 1994

The purpose of this study was to predict the actions and roles of 10 strains of representative psychrotrophic lactic acid bacteria, in kimchi fermentation, which were Isolated from kimchi and identified as Leu. mesenteroides subsp. mesenteroides, Leu. mesenteroides subsp. dextranicum, Leu. lactic, Leu. paramesenteroides, Lac. bavaricus and Lac. homahiochii. For this, 0.01% of tactic starters were inoculated in germ free Korean cabbage-juice containing 2.5% NaCl, and then cultivated for 14 days at 1$0^{\circ}C$. All strains grew actively, and reached their stationary phase in 4 days. In death phase, the slopes of curves were much different each other by strains. The acidity increased rapidly between 2 and 4 days, and the pH decreased rapidly between 2 and 3 days. The total acidity was 0.5B~0.75%, the volatile acidity 0.04~0.18% and the pH 3.55~3.85, in final cultures. The cultures of Leuconostocs were better than those of lactobacilli on flavor test. It was thought that the ripening periods of kimchi would be much reduced, and that the over ripening would be also somewhat avoided, when these strains were used as starter bacteria for kimchi and the kimchi was fermented at low temperature.

• Journal of Microbiology and Biotechnology
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• v.34 no.2
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• pp.306-313
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• 2024

Given the diversity of vegetables utilized in food fermentation and various lactic acid bacteria (LAB) populations in these materials, comprehensive studies on LAB from vegetable foods, including kimchi, are imperative. Therefore, this study aimed to investigate the obesity-related inflammation response of three metabolites-phenyllactic acid (PLA), indole-3-lactic acid (ILA), and leucic acid (LA)-produced by LAB (Companilactobacillus allii WiKim39 and Lactococcus lactis WiKim0124) isolated from kimchi. Their effects on tumor necrosis factor-α-induced changes in adipokines and inflammatory response in adipose-derived human mesenchymal stem cells were examined. The study results showed that PLA, ILA, and LA, particularly PLA, effectively reduced lipid accumulation and triglyceride, glycerol, free fatty acid, and adiponectin levels. Furthermore, the identified metabolites were found to modulate the expression of signaling proteins involved in adipogenesis and inflammation. Specifically, these metabolites were associated with enriched expression in the chemokine signaling pathway and cytokine-cytokine receptor interaction, which are critical pathways involved in regulating immune responses and inflammation. PLA, ILA, and LA also suppressed the secretion of pro-inflammatory cytokines and several inflammatory markers, with the PLA-treated group exhibiting the lowest levels. These results suggest that PLA, ILA, and LA are potential therapeutic agents for treating obesity and inflammation by regulating adipokine secretion and suppressing pro-inflammatory cytokine production.

• Food Science and Preservation
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• v.6 no.4
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• pp.514-520
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• 1999

Changes in pH, titratable acidity, CO$_2$production, reducing sugar, and lactic acid bacteria of fresh kimchi juice supplemented with combinations of 3 lactic acid bacteria and germanium(Ge)-132 or fructooligosaccharide(FO) during fermentation at 30$^{\circ}C$ were investigated to assess the potential for extending the shelf life and enhancing the functional properties in kimchi. In kimchi juice containing Ge-132, sample(I) (inoculated with a mixture of bacteriocin-producing SNF-13 strain and E. faecium) exhibited that the amounts of organic acid and evolved CO$_2$gas were lower than those of the other starter samples(II-IV). The growth of lactic acid bacteria naturally present in kimchi juice, particularly Lb. plantarum and Leu. mesentroides, may be inhibited due to competition of the isolated SNF-13 strain and E. faecium by Ge-132. During fermentation of kimchi juice containing FO sugar, the contents of organic acid and evolved CO$_2$gas On juice broth with 4 starters were predominantly higher than those of control and Ge-132 groups, and then the growth of lactic acid bacteria originated from kimchi ingredients was thought to be markedly accelerated. Our results indicated that functional properties like the extension of shelf life and increase of biological activity in kimchi were enhanced by adding Ge-132 and bacterium-producing lactic acid bacterium, which were resistant to organic acid and stimulated by Ge-132.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.424-430
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• 2000

The purpose of the study was to investigate effect of addition of mutant strains of both Leuconostoc mesenteroides and Leu. paramesenteroides on extending shelf-life of Kimchi. The mutant strains have an increased adipic acid resistance in comparison with that of their paired wild types. Addition of both strains was more effective than that of one strain alone to extend shelf-life of Kimchi. The optimal amount of inoculation was determined as 0.005% of the two mixed mutant strains with a ratio of 1 : 10, Leu. mesenteroides : Leu. paramesenteroides based on the results of acidification and organoleptic tests.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.110-115
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• 2011

Shelf-life of brined baechu cabbage was extended by pasteurization at $65^{\circ}C$ for 30 min. Starters (Leu. citreum and Lab. plantarum) were added to the pasteurized brined cabbage to supply beneficial lactic acid bacteria during kimchi fermentation. Control kimchis made with baechu cabbage without pasteurization and no addition of the starters to the pasteurized cabbage kimchi were also prepared. The fermentation characteristics and health functionalities of DPPH free radical scavenging activities and in vitro anticancer effects in AGS human gastric cancer cells were compared. The pasteurized brined cabbage could not be fermented well and the functionalities were also low; however, the addition of starter(s), especially mixed starters of Leu. citreum and Lab. plantarum to the pasteurized brined cabbage, significantly increased the counts of lactic acid bacteria, hardness (texture) and overall acceptability in sensory evaluation. The free radical scavenging activities and the anticancer effects were also increased. The fermentation patterns of starter added kimchi prepared with pasteurized brined cabbage were similar to those of naturally fermented kimchi. It seemed that growth of lactic acid bacteria during kimchi fermentation contributed to increased taste and health functionality of kimchi.

• Journal of Microbiology and Biotechnology
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• v.32 no.3
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• pp.333-340
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• 2022

Leuconostoc has been used as a principal starter in natural kimchi fermentation, but limited research has been conducted on its phages. In this study, prophage distribution and characterization in kimchi-derived Leuconostoc strains were investigated, and phage induction was performed. Except for one strain, 16 Leuconostoc strains had at least one prophage region with questionable and incomplete regions, which comprised 0.5-6.0% of the bacterial genome. Based on major capsid protein analysis, ten intact prophages and an induced incomplete prophage of Leu. lactis CBA3626 belonged to the Siphoviridae family and were similar to Lc-Nu-like, sha1-like, phiMH1-like, and TPA_asm groups. Bacterial immunology genes, such as superinfection exclusion proteins and methylase, were found on several prophages. One prophage of Leu. lactis CBA3626 was induced using mitomycin C and was confirmed as belonging to the Siphoviridae family. Homology of the induced prophage with 21 reported prophages was not high (< 4%), and 47% identity was confirmed only with TPA_asm from Siphoviridae sp. isolate ct3pk4. Therefore, it is suggested that Leuconostoc from kimchi had diverse prophages with less than 6% genome proportion and some immunological genes. Interestingly, the induced prophage was very different from the reported prophages of other Leuconostoc species.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1510-1517
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• 2012

To evaluate the probiotic potential of Bacillus polyfermenticus CJ6 isolated from meju, a Korean traditional soybean fermentation starter, its functionality and safety were investigated. B. polyfermenticus CJ6 was sensitive to all antibiotics listed by the European Food Safety Authority. The strain was also non-hemolytic, carried no emetic toxin or enterotoxin genes, and produced no enterotoxins. The resistance of B. polyfermenticus CJ6 vegetative cells and spores to simulated gastrointestinal conditions was high (60-100% survival rate). B. polyfermenticus CJ6 produced high amounts (0.36 g as a purified lyophilized form) of ${\gamma}$-polyglutamic acid (PGA). We speculate that the improved cell viability and the production of ${\gamma}$-PGA have a significant correlation. Adhesion of the strain to Caco-2 and HT-29 cells was weaker than that of the reference strain (Lb. rhamnosus GG), but it was comparable to or stronger than those of reported Bacillus spp. When B. polyfermenticus CJ6 spores were given orally to mice, the number of cells excreted in the feces was 4-fold higher than the original inocula. This suggests the inoculated spores propagated within the intestinal tract of the mice. This idea was confirmed by field emission scanning electron microscopy, which revealed directly that B. polyfermenticus CJ6 cells germinated and adhered within the gastrointestinal tract of mice. Taken together, these findings suggest that B. polyfermenticus CJ6 has probiotic potential for both human consumption and use in animal feeds.