• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.282-291
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• 1999

Lactic acid bacteria were isolated from Kimchi and screened for bacteriocin. A total of 99 strains showed antimicrobial activity when grown on solid media, yet only 10 showed antimicrobial activity in liquid media. Strain H-559, identified as Lactococcus lactis subsp. lactis, exhibited the strongest inhibitory activity and was active against pathogenic bacteria including Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus as well as other lactic acid bacteria. The antimicrobial substance produced by L. lactis subsp. lactis H-559 was confirmed to be a bacteriocin by the treatment of $\alpha$-chymotrypsin, and protease type Ⅸ and ⅩIV. The bacteriocin activity remained stable between pH 2.0 and pH 11.0 and during heating for 10 min at $100^{\circ}C$. The bacteriocin production started in the exponential phase and stopped in the stationary phase. L. lactis subsp. lactis H-559 showed the highest bacteriocin activity at a culture temperature of $25^{\circ}C$, and an inverse relationship between the bacteriocin productivity and mean growth rate at different culture temperatures was observed. The mean growth rate and bacteriocin productivity of L. lactis subsp. lactis H-559 increased as the initial pH of the media increased.

• 한국미생물·생명공학회지
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• 제27권1호
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• pp.15-22
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• 1999

Various lactic acid bacteria were isolated from Korean Kimchi in order to study their antimutagenic substances. Ames test using Salmonella typhimurium TA98 and TA100 showed the strain KLAB21 to have the highest antimutagenic activity among the 230 isolated strains against MNNG (N-methyl-N'-nitro-N-nitrosoguanidine), NPD (4-nitro-O-phenylenediamine), NQO (4-nitrosoquinoline-1-oxide) and AFB1 (aflatoxin B1). The strain was identified as Lactobacillus plantarum based on its morphological, cultural and physiological characteristics. Antimutagenic activity of L. plantarum KLAB21 was found in culture supernatant suggesting the bacterium secrete antimutagenic substance in the media. No mutagenic activity was found in the culture supernatant. The isolated strain L. plantarum KLAB21 showed much higher antimutagenic activity than L. plantarum IAM1261 which is being used industrially for fermented milk production. The antimutagenic activity of L.plantarum KLAB21 was reconfirmed by the spore-rec assay using spores of Bacillus subtilis H17($Rec^+$) and M45($Rec^-$).

• Food Science and Biotechnology
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• 제17권4호
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• pp.857-860
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• 2008

S-Adenosyl-L-methionine (SAM) is a bioactive material used in the treatment of depression, osteoarthritis, and liver disease. To obtain lactic acid bacteria (LAB) producing high concentrations of SAM, LAB were isolated from commercial kimchi and from prepared kimchi products that contained shrimp jeotgal (fermented salty seafood) or sand lance jeotgal or that were fermented at 5 or $10^{\circ}C$, respectively, when pH was 4.2 to 4.8 and titratable acidity 0.6 to 0.9. Among the 179 LAB strains isolated from the fermented kimchi products, the genus Leuconostoc produced the highest intracellular level of SAM (1.58 mM) and Lactobacillus produced the second highest level (up to 1.47 mM) in the strain culture. This is the first study to quantify SAM in LAB isolated from fermented kimchi prepared by a general kimchi recipe. Ultimately, the selected strains (Leuconostoc mesentroides subsp. mesenteroides/dextranicum KSK417, L. mesentroides subsp. mesenteroides/dextranicum KJM401, and Lactobacillus bifermentans QMW327) could be useful as starters to manufacture fermented foods containing high levels of SAM.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.13-17
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• 1994

We estabilished the procedure for isolation of Streptococcus salivarius subsp. thermophilus from raw milk. First, urease-producing lactic acid bacteria in raw milk were screened on the HY agar medium containing urea. Thereafter the urease-producing colonies were tested the ability to ferment maltose and to grow at43$\circ $C. We obtained about 400 maltose-negative colonies that grew at 43$\circ $C. No significant difference in carbohydrate fermentation test for isolated and type strains(S. salivarius subsp. thermophilus ATCC 19258 and ST-4) was found. And all of the isolated strains were able to ferment galactose. Furthermore, it was investigated that the cellular fatty acid profiles of isolated strains were similar to that of type strains. These results indicated that the isolated strains from raw milk were S. salivarius subsp. thermophilus. But when the isolated and type strains were incubated in 12% reconstituted skim milk at 43$\circ $C, the isolates produced lactic acid more slowly than the type strains.

• Food Science and Biotechnology
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• 제15권1호
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• pp.86-90
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• 2006

Two lactic acid bacteria (LAB) with high ${\gamma}$-aminobutyric acid (GABA)-producing capacity were isolated from naturally aged cheese. Examination of the biochemical features using an API kit indicated that the two strains belonged to Lactobacillus. They were gram positive, rod-type bacteria, and fermented arabinose, melezitose, melibiose and xylose, but did not utilize cellobiose or trehalose. 16S rDNA sequencing analysis confirmed that they were Lactobacillus buchneri and Lactobacillus sp. They were accordingly named as Lactobacillus buchneri OPM-1 and Lactobacillus sp. OPM-2, and could produce GABA from MRS broth supplemented with 10 g/L of monosodium glutamate (MSG) at a productivity of 91.7 and 116.7 mg/L/hr, respectively. Cell extracts of L. buchneri OPM-1 and Lactobacillus sp. OPM-2 showed glutamate decarboxylase (GAD) activity, for which the optimum pH and temperature were 5.5 and $30^{\circ}C$, respectively.

• Food Science and Biotechnology
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• 제14권4호
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• pp.518-522
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• 2005

Yogurt containing high ${\gamma}$-aminobutyric acid (GABA) was developed using lactic acid bacteria and germinated brown rice. Lactobacillus acidophilus, L. plantarum, and L. brevis OPY-1 strains were inoculated into Lactobacillus MRS broth for use as yogurt starter. After treatment with 5% monosodium glutamate in MRS broth, L. brevis OPY-1 strain isolated from Kimchi produced GABA concentration of 8,003.28 nmol/mL. Starter was inoculated into fermentation substrate mixture containing germinated brown rice extract and blend of powdered whole milk and skim milk. Samples were incubated, and viable cell colonies were counted. Highest number of lactic acid bacteria was reached between 16 and 20 hr. Concentrated rice milk fermented with high GABA-producing strain contained GABA concentrations of $137.17\;{\mu}g/g$ D.W., whereas concentrated fermented milk prepared by conventional method contained GABA of $1.29\;{\mu}g/g$ D.W. Sensory evaluation panelists gave favorable ratings to fermented rice milk containing high GABA concentration.

• Preventive Nutrition and Food Science
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• 제21권1호
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• pp.52-56
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• 2016

This study was performed to investigate the antifungal substances and the antifungal activity against fungi of lactic acid bacteria (LAB) isolated from kimchi. LAB from kimchi in Imsil showed antifungal activity against Penicillium brevicompactum strain FI02. LAB LI031 was identified as Lactobacillus sakei subsp. Antifungal substances contained in L. sakei subsp. ALI033 culture media were unstable at high pH levels. Both, the control and proteinase K and protease treated samples showed clear zones, suggesting that the antifungal substances produced by ALI033 were non-protein substances unaffected by protesases. Both, the control and catalase showed clear zones, suggesting that the antifungal metabolite was not $H_2O_2$. The molecular weights of the antifungal substances were ${\leq}3,000Da$. The organic acid content of crude antifungal substances produced by L. sakei subsp. ALI033 showed high concentrations of lactic acid (502.47 mg/100 g). Therefore, these results suggest that antifungal substance produced by L. sakei subsp. ALI033 is most likely due to its ability in producing organic acid.

• 한국식품과학회지
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• 제35권6호
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• pp.1244-1247
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• 2003

발효 및 유산균 제품에 모유만을 먹은 생후 3개월된 유아의 분변으로부터 bromocresol pule을 함유한 MRS 배지에서 노란색의 집락을 형성하는 균주들을 내산성 및 담즙산 내성이 우수한 13종의 Lactobacillus 균주들을 분리하였으며 당발효성 및 생화학적 실험을 토대로 분리된 유산균들을 동정하였다. 최종적으로 선발한 균주를 L. acidophilus로 KY1909로 명명하였다. Lactic acid 생성 능력을 평가한 후 이성질체를 분석한 결과 상업적으로 이용되는 L. acidophilus NCFM, L. acidophilus CH5, L. acidophilus NOCKS 균주들은 전체 lactic acid 중에서 L(+) form이 차지하는 비율이 각각 52.49, 40.63 및 63.13%로 나타났으나, L. acidophilus KY1909는 L(+) lactic acid의 비율이 93.96%로 나타났다.

• 한국식품영양과학회:학술대회논문집
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• 한국식품영양과학회 2001년도 International Symposium on Food,Nutrition and Health for 21st Century
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• pp.161-169
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• 2001

Lactic acid producing bacteria were isolated from baby feces and characterized to be used as a probiotic with anti Helicobacter pylori functions. The selected bacteria had inhibition activity on the adherance and growth of H. pylori. These bacteria had additional beneficial characteristics for the probiotic such as antibacterial activity, antitumor activity, immunostimulation activity, resistance to antibiotic and bile salt, ability to bind to the intestinal cells, and safe for the human use.

• 미생물학회지
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• 제54권4호
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• pp.398-409
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• 2018

본 연구에서는 된장으로부터 바이오제닉 아민 생성 바실러스균과 박테리오신 생산유산균은 16S rRNA 염기서열 분석을 통해 동정하였고, 이들 균주들의 혼합 배양으로 제조한 청국장의 이화학적 및 미생물학적 특성을 조사하였다. 총10종의 시료로부터 바이오제닉 아민을 생성하는 바실러스균은 Bacillus licheniformis DB102, B. subtilis DB203, B. stearothermophilus DB206, B. pumilus DB209, B. subtilis DB310, B. coagulans DB311, B. cereus DB313, B. amyloliquefaciens DB714, B. amyloliquefaciens DB915, B. licheniformis DB917, B. cereus DB1019, B. subtilis DB1020, B. megaterium DB1022로 동정되었다. 바이오제닉 아민 생성 바실러스균에 대해 항균 활성을 나타낸 박테리오신 생산균은 Lactobacillus plantarum DLA 205, L. brevis DLA501, L. fermentum DLA509, L. acidophilus DLA703 및 Enterococcus faecalis DLA804로 확인되었다. 유산균의 박테리오신은 농도의존적으로 바이오제닉 아민 생성균의 생균수 및 아민 생성능을 유의하게 감소시켰다. 따라서 유해 아민 생성균에 대한 항균 활성을 나타낸 유산균의 증식에 따라 유산균과 바실러스균을 혼합 배양하여 제조한 청국장의 pH, 암모니아태 질소 함량 및 바이오제닉 아민 함량은 대조구에 비해 유의하게 감소되었다.