• Journal of Microbiology and Biotechnology
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• 제27권12호
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• pp.2112-2118
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• 2017

Leuconostoc mesenteroides is used as a starter to produce high-quality kimchi products. In this study, an efficient and economical cabbage juice medium (CJM) was developed by process optimization of cabbage extraction and pasteurization and by compositional supplementation of various lacking nutrients. The pasteurized cabbage juice was determined to be a good medium candidate to cultivate L. mesenteroides, showing maximal cell numbers ($9.85{\times}10^8CFU/ml$) after 24 h. Addition of sucrose and yeast extract with soy peptone resulted in increment of bacterial cell counts in CJM, showing the supplementing effect of the lacking nutrients. Furthermore, addition of shell powder gave a protective effect on bacterial cells by preventing pH decline and organic acid accumulation in CJM, resulting in a 2-fold increase of bacterial counts. The optimized composition of CJM was 70% cabbage juice diluted with water, 0.5% (w/v) sucrose, 1% (w/v) yeast extract, 1% (w/v) soy peptone, and 1.5% (w/v) ark shell powder. The CJM developed in this study was able to yield a comparable level of bacterial counts with MRS medium and reduced the cost by almost 10-fold.

• 한국식품저장유통학회지
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• 제7권2호
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• pp.222-227
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• 2000

Antimutagenic activity of crushed kimchi fermented with starter under various conditions such as temperature(5-20$^{\circ}C$), salt concentration(2-10%), addition rate of starter (0-20%) was investigated. The kimchi was fermented with crushed Chinese cabbage without salting, red pepper powder, crushed garlic, crushed ginger, anchovy juice and starter. Well fermented kimchi juice(fermented at 10$^{\circ}C$ for 15 days) and sterilized radish juice was used as a source of lactic acid bacteria and starter medium, respectively. Antimutagenic activity showed the highest in the crushed kimchi fermented at 15$^{\circ}C$ for 15 days, 4% salt concentration, 5% starter added, respectively. The inhibition rate of mutagenic activity of the kimchi against S. typhimurium TA98 induced by NQO and S. typhimurium TA100 induced by MNNG was 56.41% and 60.11%, respectively. And the inhibition rate of the kimchi juice showed 56-60% per 100ul.

• 한국미생물·생명공학회지
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• 제38권4호
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• pp.481-485
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• 2010

Lactobacillus plantarum strain KK3 with tannase activity was isolated from Gochunipkimchi (red pepper leaf kimchi) and showed a high antagonistic activity against five kinds of food pathogens. Strain KK3 secreted antibacterial compound into culture medium and 24-h culture in MRS broth at $30^{\circ}C$ was enough for the antibacterial compound production. The crude antibacterial compound prepared from culture supernatant inhibited the growth of some Gram-negative bacteria and Bacillus cereus but not Listeria monocytogenes. The antibacterial activity was sensitive to proteinase K treatment, confirming its proteinaceous nature (bacteriocin). The crude bacteriocin was active in the pH range 3.5-8.5 and extremely stable after 15 min of heat treatment at $121^{\circ}C$. The strain KK3 produced equally active bacteriocin in Chinese cabbage juice as it produced in MRS broth.

• Food Science and Biotechnology
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• 제14권4호
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• pp.503-508
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• 2005

Screening for antilisterial activity was performed in about three thousand isolates of lactic acid bacteria (LAB) from Chinese cabbage kimchi, and finally based on the relatively stronger antilisterial activities eight bacterial strains were selected. The bacteria were further characterized in terms of their tolerance to artificial gastric juice, pH 2.5, bile salts (0.3% oxgall), and to the different NaCl concentrations. Of the isolates, YK005 was especially investigated for its physiological characteristics due to its inhibitory activity against gram-positive Listeria monocytogenes as well as gram-negative Escherichia coli O157:H7, as they have been constantly reported to be resistant against bacteriocins produced by a number of LAB strains. YK005 was found to be rod-shaped, $3.8\;{\mu}m$ long ${\times}\;0.5\;{\mu}m$ wide, non-sporeforming, non-motile, catalase-negative, and produced gas from glucose (heterolactic). Based on the biochemical data obtained by API 50 CHL medium, the isolate was tentatively identified as Lactobacillus brevis. To validate the result obtained by the biochemical identification, rRNA-based PCR experiments using a pair of species-specific primers for L. brevis were conducted and a single band of 1400 bp was observed, which strongly indicated that YK005 belongs to L. brevis. The LAB isolates are potentially exploited as human probiotic organisms and are employed to control some food-borne pathogens like L. monocytogenes.