• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.288-292
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• 1993

An agar medium(HY) was developed to detect the urease-producing lactic acid bacteria. HY medium was prepared with the addition of tryptone, glucose and tween 80 to the supernatant of autoclaved skim milk and yeast extract mixture. There was no difference in eumeration of lactic acid bacteria between the HY and commercial media, such as M17, MRS and BCP agar. The urease activity of Streptococcus salivarius subsp. thermophilus was detected on the HY agar medium contained urea by the color change of bromocresol purple as the pH indicator, but not on the commerical agar media. Furthermore, it was succeeded to screen the urease activity of bacteria in skim milk used as a raw material in dairy product manufacture. Therefore, HY medium was proved to be suitable for the screening of urease-producing lactic acid bacteria.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.1031-1035
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• 2002

This study was carried out to obtain conjugated linoleic acid (CLA) producing lactic acid bacteria for further study on the enzymes related to the production of CLA which has gained considerable attention and on the development as a probiotic culture. Total 34 lactic acid bacteria were isolated from 19 feces samples of healthy babies. CLA forming ability was measured spectrophotometrically by the modification of linoleate 12-cis, 11-trans-isomerase activity measuring method, and CLA of the cultures were extracted, methylated, and examined by HPLC analysis. CLA methyl ester of only one culture showing the highest value of CLA forming ability could be detected by HPLC analysis. The culture was found to be Gram positive, rods and catalase negative. It grows at $45^{\circ}C$ but not at $15^{\circ}C$, and was identified to be Lactobacillus fermentum on the basis of the biochemical characteristics and the utilization of substrates. These results provide an efficient experimental method to screen CLA producing lactic acid bacteria.

• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.305-315
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• 1994

Nineteen strains of bacteriocin-producing lactic acid bacteria were isolated from 432 Kimchi samples, and identified by the comprehensive biochemical and morphological tests verifying their cellular fatty acid composition. Using partially purified bacteriocins from these isolates, their inhibitory activities against other lactic acid bacteria and some pathogens, and sensitivity to enzyme and heat treatments were tested. The isolates were identified as Lactobacillus plantarum (2 strains), L curvatus (2 starins), L brevis (2 strains), Enterococcus faecium (6 strains), Leuconostoc mesenteroides subsp. mesenteroides (1 strain) and Lactobacillus sp. (6 strains). The bacteriocins produced by E. faecium strains provided the broadest spectrum of inhibition, affecting against other Gram-positive bacteria including lactic acid bacteria and health-threatening bacteria such as Clostridium perfringens and Listeria monocytogenes. The bacteriocins of Lactobacillus sp., L plantarum and L brevis strains were capable of inhibiting many strains of the lactic acid bacteria, whereas those of L curvatus and L mesenteroides subsp. mesenteroides strains were only inhibitory to a few strains. Generally, the inhibitory activities of both E. faecium and Lactobacillus sp. strains were greater than those of other producer strains. The bacteriocins from the isolates were sensitive to several proteolytic enzymes, and those of L curvatus and L mesenteroides subsp. mesenteroides were also sensitive to lipase and $\alpha$-amylase as well as to proteolytic enzymes. The bacteriocins from the strains of Lactobacillus sp. and a strain of L. brevis were resistant to autoclaving.

• Journal of Microbiology
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• v.45 no.6
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• pp.515-520
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• 2007

Vaginal lactic acid-producing bacteria of 80 pre-menopausal women were studied by isolation on Blood and DeMan-Rogosa-Sharpe agar, PCR with group-specific primers for Lactobacillus-denaturing gradient gel electrophoresis (DGGE), and PCR with specific primers for V3 region in 16S rRNA-temporal temperature gel electrophoresis (TTGE). Conventional isolation method on media detected only one lactobacillus (Lactobacillus brevis) while TTGE detected only Lactobacillus sp. DGGE detected seven Lactobacillus species; L. coleohominis, L. crispatus, L. iners, L. reuteri, L. rhamnosus, L. vaginalis, and Leuconostoc lactis. L. acidophilus and L. gasseri, which are prevalent in Western women, were not detected in Korean women. Furthermore, L. rhamnosus, Leuc. lactis, L. coleohominis, and Weissella cibaria, which were not previously reported in the vaginal microbiota of Korean women, were detected. The five most prevalent LABs in vaginal microbiota in Korean women were L. iners, Enterococcus faecalis, L. crispatus, Leuc. lactis, and W. cibaria.

• Fisheries and Aquatic Sciences
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• v.19 no.10
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• pp.42.1-42.10
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• 2016

The objectives of this study were to identify the histamine-forming bacteria and bacteriocin- producing lactic acid bacteria (LAB) isolated from Myeolchi-jeot according to sequence analysis of the 16S rRNA gene, to evaluate the inhibitory effects of the bacteriocin on the growth and histamine accumulation of histamine-forming bacteria, and to assess the physico-chemical properties of the bacteriocin. Based on 16S rRNA gene sequences, histamine-forming bacteria were identified as Bacillus licheniformis MCH01, Serratia marcescens MCH02, Staphylococcus xylosus MCH03, Aeromonas hydrophila MCH04, and Morganella morganii MCH05. The five LAB strains identified as Pediococcus acidilactici MCL11, Leuconostoc mesenteroides MCL12, Enterococcus faecium MCL13, Lactobacillus sakei MCL14, and Lactobacillus acidophilus MCL15 were found to produce an antibacterial compound with inhibitory activity against the tested histamine-producing bacteria. The inhibitory activity of these bacteriocins obtained from the five LAB remained stable after incubation at pH 4.0-8.0 and heating for 10 min at $80^{\circ}C$; however, the bacteriocin activity was destroyed after treatment with papain, pepsin, proteinase K, ${\alpha}$-chymotrypsin, or trypsin. Meanwhile, these bacteriocins produced by the tested LAB strains also exhibited histamine-degradation ability. Therefore, these antimicrobial substances may play a role in inhibiting histamine formation in the fermented fish products and preventing seafood-related food-borne disease caused by bacterially generated histamine.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.43.2-43.2
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• 2008

• Journal of Nutrition and Health
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• v.51 no.1
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• pp.1-13
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• 2018

Purpose: This review article provides an overview of the trends of research papers on the health benefits of kimchi and kimchi lactic acid bacteria published from 1995 to 2017. Methods: All publications from 1995 to 2017 regarding kimchi and kimchi lactic acid bacteria were collected, reviewed, and classified. This review article covers the publications of the health benefits of kimchi and kimchi lactic acid bacteria on experimental, clinical trials, and epidemiology studies. Results: The number of publications on kimchi over the period were 590: 385 publications in Korean and 205 publications in English. The number of publications on the health benefits of kimchi and kimchi lactic acid bacteria were 95 in Korean and 54 in English. The number of publications on kimchi and kimchi lactic acid bacteria were 84 and 38, respectively, in the experimental models. Ten research papers on kimchi in clinical trials and 7 publications in epidemiology were found. Kimchi or kimchi lactic acid bacteria had protective effects against oxidative stress, mutagenicity, toxicity, cancer, dyslipidemia, hypertension, immunity, and inflammation in in vitro, cellular, and in vivo animal models. Moreover, kimchi had effects on the serum lipids, intestinal microbiota, iron status, obesity, and metabolic parameters in human clinical trials. In epidemiology, kimchi had effects on hypertension, asthma, atopic dermatitis, rhinitis, cholesterol levels, and free radicals. Conclusion: This review focused on the publications regarding the health benefits of kimchi and kimchi lactic acid bacteria, suggesting the future directions of studies about kimchi and kimchi lactic acid bacteria by producing a database for an evaluation of the health benefits of kimchi.

• The Korean Journal of Food And Nutrition
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• v.12 no.1
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• pp.69-76
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• 1999

In order to screen lactic acid bacterial starter having high antibacterial activity and giving good flavor in Dongchmi for Naengmyon antibacterial activity and acid producing ability of 24 strains of Kimchi lactic acid bacteria were tested. Among 24 strains tested Leuconostoc mesenteroides subsp. mesenteroides C16, Leu. paramesenteroides C18 Lactobacillus bavaricus B01, B06, C19, C32 Lac. homohiochii B21 and B22 showed high antibacterial activity and their antibacterial activities were more active against Listeria monocytogenes and Staphylococcus aureus than against Escherichia coli and Salmonella typhimurium. The odors of Dongchimi-juices fermented with Leu. mesenteroides or Leu. paramesenteroides were more favorable than those with Lac. bavaricus or Lac. homohiochii. But the odors of Naengmyon-broths which were made with each Dongchimi-juice were not significantly different each other. In consideration of antibacterial ac-tivity and flavor of Dongchimi-juice two strains of lactic acid bacteria Lac. homohiochii B21 and Leu. mes-enteroides subsp. mesenteroides C16 were finally screened out as Dongchimi starters.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.113-125
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• 2018

Purpose of the present study was to investigate the factors affecting the production of antibacterial substances and histamine in rennet curd prepared by inoculation of histamine-producing lactic acid bacteria (LAB) and probiotic LAB. Probiotic Lactobacillus sakei PIL52 and Lactobacillus plantarum FIL20 produced strong antimicrobial agents against histamine-producing bacteria Lactobacillus brevis LAS129, Enterococcus faecium SBP12, and Enterococcus faecalis SBP58. The lactic acid and crude bacteriocin produced from the probiotic LAB inhibited histamine-producing bacteria in a concentration-dependent manner. As the number of probiotic LAB inoculated for the production of rennet curd increased, the antibacterial activity against histamine-producing bacteria was elevated due to the increased amount of lactic acid and crude bacteriocin in the sample. The growth of probiotic LAB as well as histamine-producing bacteria was inhibited by addition of 10% NaCl, thus the antibacterial substances and histamine contents in rennet curd were significantly lower than those of the control (P < 0.05). Meanwhile, the histamine content was not significantly increased when the rennet curd prepared by mixing probiotic LAB and histamine-producing bacteria was stored at $25^{\circ}C$ for 5 days. However, the amount of histamine detected in the rennet curd was significantly (P < 0.05) increased because the antibacterial activity of the bacteriocin produced by the probiotic LAB was decreased at $20^{\circ}C$ for 20 days.

• Journal of Nutrition and Health
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• v.35 no.9
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• pp.912-918
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• 2002

In nature, two different types of fructose polymers (fructan) are generally found in dietary fibers; these are the fructose homopolymers levan, which is of high molecular weight and is $\beta$-(2,6)-linked, and inulin, which is of low molecular weight and is $\beta$-(2,1)-linked. The effects of levan and inulin on the intestinal physiology of rats were compared. Sprague Dawley rats were fed one of three diets for 3 weeks: a control diet, a basal diet containing 7% of levan, and a basal diet containing 7% of inulin. Cecal enlargement, together with the lowering of cecal pH, occurred in rats fed on the levan and inulin diets (p < 0.05). The levan and inulin diets resulted in a two-fold increase in the amount of short-chain fatty acids in the cecum, when compared to the control diet. The number of total microbes and of lactic acid-producing bacteria in the feces were higher in rats fed the fructan diets than those in rats fed control diet (p < 0.05). The levan diet also significantly increased the cecal $\alpha$-galactosidase activity by 3.8-fold, when compared to the control diet, indicating that levan stimulated the growth of Bifidobacteria in the cecum. These results show that the intake of levan and inulin stimulated the growth of lactic acid-producing bacteria in the cecum and thereby improved intestinal conditions in rats. (Korean J Nutrition 35(9) : 912~918,2002)