• Food Science and Biotechnology
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• 제14권1호
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• pp.49-57
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• 2005

Enterococcus faecium MJ-14, having strong antilisterial activity, was isolated from Korean fermented food, Meju. MJ-14 showed the same phenotypic characteristics, but different sugar utilization, as reference strain, E. faecium KCCM12118. It could utilize D-xylose, amygdaline, and gluconate, whereas E. faecium KCCM12118 could not. Optimal condition for bacteriocin production by E. faecium MJ-14 was at $37^{\circ}C$ and pH 7.0. Bacteriocin activity appeared in mid exponential phase and increased rapidly up to stationary phase. Activity was significantly promoted in MRS broth containing 3.0% glucose, 1.5% lactose, 2.0% peptone, or 1.5% tryptone. Bacteriocins effectively inhibited Enterococcus faecalis and Listeria spp. of Gram-positive bacteria, and Helicobacter pylori of Gram-negative bacteria, but did not inhibit yeasts and molds. They were stable against heat (for 30 min at $100^{\circ}C$), pH (3.0-9.0), long-term storage (for 60 days at 4 or $-20^{\circ}C$), and enzymatic digestion by catalase, proteinase K, papain, lysozyme, trypsin, chymotrypsin, and lipase, etc. Bacteriocin activity was completely inhibited by protease and pepsin, and 50% by ${\alpha}$-amylase. Studies on PCR detection of enterocin structural genes revealed bacteriocins are identical to enterocins A and B.

• 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.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1228-1236
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• 1997

Lactobacillus strains were isolated from volunteer's feces, including from newly-born infants and adults in their 20's, by using differential MRS-BPB plates. Total 56 presumptive Lactobacillus strains were isolated and the bacteriocin productions by the isolates were examined by agar diffusion method. Six bacteriocin-producing strains were confirmed. Among them, two isolates, HU-1 and H22-3, showed the most outstanding antimicrobial activities, which were not affected by pH adjustments or catalase treatments of culture. HU-1 was originated from a two-years old boy and H22-3 was originated from a newly-born infant. HU-1 and H22-3 had the same morphology(short rod) when examined by scanning electron microscope, and the same biochemical traits including growth temperature range, salt tolerance and sugar-fermenting abilities. But the growth-inhibition spectrum and plasmid profiles of HU-1 and H22-3 were different. Both strains inhibited the growth of various Gram (+) microorganisms including Listeria monocytogenes. Micrococcus luteus, and Staphylococcus aureus in addition to many species of lactic acid bacteria, indicating the production of broad-spectrum bacteriocins. Bacteriocins produced by HU-1 and H22-3 were stable up to 90℃, 15 min heat treatments. Their activities were not affected by pepsin or trypsin treatments but destroyed by proteinaseK or pronase treatments.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2000년도 Proceedings of 2000 KSAM International Symposium and Spring Meeting
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• pp.53-60
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• 2000

Strain BH5 was isolated from naturally fermented Kimchi and identified as a bacteriocin producer, which has bactericidal activity against Micrococcus flavus ATCC 10240. Strain BH5 was identified tentatively as Lactococcus lactis by the API test and some characteristics. Lactococcus lactis BH5 showed a broad spectrum of activity against most of the non-pathogenic and pathogenic microorganisms tested by the modified deferred method. The activity of lacticin BH5, named tentatively as the bacteriocin produced by Lactococcus lactis BH5, was detected at the mid-log growth phase, reached its maximum during the early stationary phase, and decreased after the late stationary phase. Lacticin BH5 also showed a relatively broad spectrum of activity against non-pathogenic and pathogenic microorganisms as tested by the spot-on-lawn method. Its antimicrobial activity on sensitive indicator cells was completely disappeared by protease XIV or ${\alpha}$-chymotrypsin. The inhibitory activities of lacticin BH5 were detected during treatments up to 100$^{\circ}C$ for 30 min. Lacticin BH5 was very stable over a pH range of 2.0 to 9.0 and was stable with all the organic solvents examined. The cell concentration and bacteriocin production in strain BH5 were maximum when grown at 30$^{\circ}C$ in a modified MRS medium supplemented with 0.5% tryptone, 1.0% yeast extract, and 0.5% beef extract as nitrogen sources. It demonstrated a typical bactericidal mode of inhibition against Micrococcus flavus ATCC 10240. Lacticin BH5 was purified through ammonium sulfate precipitation, ethanol precipitation, and CM-Sepharose column chromatography. The apparent molecular mass of lacticin BH5 was estimated to be in the region of 3.7 kDa, by the direct detection of bactericidal activity after SDS-PAGE. Mutant strain NO141 which was isolated by nitrosoguanidine mutagenesis produced about 4 fold more bacteriocin than the wild type.

• 미생물학회지
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• 제51권3호
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• pp.288-299
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• 2015

숙성된 백김치로부터 얻은 Lactobacillus brevis BK11의 증식과 항균물질 생산에 대한 배양용 배지 종류, 공기 조성, 초기 pH, 배양온도 및 시간과 프리바이오틱스의 영향을 조사하였다. L. brevis BK11의 증식과 항균물질 활성은 BHI와 M17 배지 보다는 MRS 배지 상에서 더 높게 나타났으며, 배지의 초기 pH 6.0에서 생산량이 최대에 이르렀다. 혐기적 조건보다는 호기적 및 미호기적 조건에서 배양했을 때와 $25^{\circ}C$ 보다는 $30^{\circ}C$와 $37^{\circ}C$ 온도에서 배양했을 때 균 성장과 항균물질 생산에 유리하였다. BK11 균주는 배양 24시간 만에 정지기에 도달하였고, 36시간 후부터는 생균수가 감소되었고, 배양상등액과 박테리오신 용액의 항균 활성은 $37^{\circ}C$, 24-30시간 배양했을 때 가장 높았다. 세포수와 유산 및 박테리오신 생산은 프락토올리고당 1-2% 첨가한 경우에 가장 높았으나, 이뉼린과 라피노오스는 균 증식에 별다른 도움을 주지 못했다. 결과적으로 L. brevis BK11의 항균물질 생산은 세포수와 관계 있었으며, 이러한 최적 조건 하에서 배양한 경우 Helicobacter pylori ATCC 43504의 성장을 효과적으로 저해할 수 있다.

• 한국축산식품학회지
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• 제30권1호
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• pp.66-72
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• 2010

Pediococcus pentosaceus SA131 was isolated from jeotgal, is the bacteriocin producer against bovine mastitis pathogens, Streptococcus uberis E290, Enterococcus gallinarum E362, and Staphylococcus epidermidis ATCC 12228. The medium composition for pediocin SA131 production by P. pentosaceus SA131 was optimized using response surface methodology. Component of medium was studied as carbon source (glucose, fructose, lactose, glycerol, sucrose, maltose, and mannitol), nitrogen source (beef extract, yeast extract, peptone, malt extract, and tryptone), mineral and surfactant ($MgSO_4$, $KH_2PO_4$, $(NH_4)_2SO_4$, $MnSO_4$, NaCl, sodium acetate, and Tween 80). Through one factor-at-a-time experiment, glucose, fructose, yeast extract, malt extract, NaCl, $MgSO_4$, and Tween 80 were determined as the good ingredient. The effects of major factors for pediocin SA131 production were investigated by two-level fractional factorial designs (FFD). By a $2^4$ FFD, fructose, yeast extract, and $MnSO_4$ were found to be the important factors for the bacteriocin production. Subsequently, a $2^3$ central composite design (CCD) was adopted to derive a statistical model for optimizing the composition of the fermentation medium. The estimated optimum composition for the production of pediocin SA131 by P. pentosaceus SA131 was as follows; 0.13% fructose, 1% glucose, 1.8% yeast extract, 2.58% $MnSO_4$, 0.2% NaCl, and 0.2% Tween 80. The pediocin production under optimized medium was increased to 1,000 AU/mL, compared to the 400 AU/mL in MRS medium.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.69-72
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• 2005

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2003년도 International Meeting of the Microbiological Society of Korea
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• pp.39-39
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• 2003

• KSBB Journal
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• 제19권4호
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• pp.291-294
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• 2004

박테리오신의 일종인 leucocin A로 형질전환된 효모가 보이는, B. subtilis에 대한 항균 활성을 파악하기 위하여 형질 전환되지 않은 효모와 형질전환된 효모를 배양하면서 시간별로 채취하여 광학밀도, 건조중량, 총단백질량, 단백질 분해효소 그리고 항균활성을 측정하였다. Leucocin A의 항균활성은 성장양상과 비례하였다. 배양초기에 비해 12시간 배양 후에 항균활성이 3배 이상 증가하는 것으로 나타났고, 이때 B. subtilis의 성장이 70.57% 감소하는 것으로 나타났다. 정지기 이후에는 항균활성이 급속히 감소하였는데, 이는 항균활성을 보이는 leucocin A가 단백질이고, 단백질 분해효소가 정지기 이후 증가한 것에 의한 것으로 사료되었다. 이 연구는 향후 식품산업 등에 사용할 수 있는 bacteriocin의 산업적 생산에 필요한 기초자료를 제공할 수 있을 것이다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.554-557
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• 2000

Strain JV3 was isolated from commercial Swiss cheese products and identified as a bacteriocin producer, which has bactericidal activity against Leuconostoc mesenteroides KCCM 11324. Strain JW3 was identified tentatively as Lactococcus lactis by the API test. The activity of lacticin JW3, named tentatively as the bacteriocin produced by Lactococcus lactis JW3, was detected during the mid-log growth phase, and reached a maximum during the early stationary phase, and decreased after the late stationary phase. Its antimicrobial activity on sensitive indicator cells was completely disappeared by protease IV. The inhibitory activities of lacticin JW3 were detected during treatments of up to $121\'^{circ}C$ for 15 min. Lacticin JW3 was very stable over a pH range of 2.0 to 9.0 The apparent molecular mass of lacticin JW3 was estimated to be in the region of 3-3.5kDa, which was determined by the direct detection of bactericidal activity after SDS-PAGE.