• 한국축산식품학회지
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• 제35권2호
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• pp.211-215
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• 2015

From the previous study, Enterococcus faecium SH01 was isolated from mukeunji, an over-ripened kimchi, and it produced bacteriocin SH01. Bacteriocin SH01 showed an inhibitory effect against Listeria monocytogenes ATCC 19111, a bacterial strain causing human listeriosis. Crude bacteriocin SH01 was purified by ammonium sulfate precipitation and its inhibitory activity at two concentrations (500 and 1,000 AU/g) against Listeria monocytogenes ATCC 19111 was investigated in ground beef at increasing temperatures (5, 10, 15, and 20℃) for 8 d. The number of Listeria monocytogenes ATCC 19111 significantly decreased (p<0.05) as the concentration of bacteriocin increased from 500 to 1,000 AU/g. Intrinsic crude protease activities in ground beef were examined and increased as the temperature increased. Experiments varying both the concentrations of added bacteriocin SH01 and temperature demonstrated a maximum inhibition (2.33 log reduction of bacteria) in samples containing 1,000 AU/g of bacteriocin SH01 incubated at 20℃. When the crude bacteriocin SH01 solution (1,280 AU/mL) was incubated with crude protease solutions at different temperatures, its activity decreased by only half (640 AU/mL), as assessed in an agar well diffusion assay. The finding that the antilisterial activity of bacteriocin SH01 increased with temperature can be explained by the fact that higher temperatures increase bacterial membrane fluidity, thereby promoting the cellular penetration of bacteriocin SH01 into L. monocytogenes. Bacteriocin SH01 may be an excellent candidate as a biopreservative for controlling L. monocytogenes growth in ground beef.

• 한국축산식품학회지
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• 제31권6호
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• pp.952-959
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• 2011

여러 원천에서 분리한 유산균을 대상으로 신규 bacteriocin 생산 유산균을 선발하고 API 당 발효성과 16S rDNA를 분석한 결과 P. damnosus 로 동정되어 JNU 534로 명명하였다. P. damnosus JNU 534에 의해 생산된 bacteriocin은 다수의 유산균과 L. monocytogenes의 생육을 억제하였지만, Gram음성균을 포함한 다른 병원성균들은 저항성을 나타냈다. Bacteriocin의 생산은 대수기 초반에 시작되어 정지기 초기에 최대 활성에 이르렀다. Bacteriocin은 pH 2-9의 넓은 범위와 $100^{\circ}C$에서 15분간의 열처리에 대해서도 안정성을 유지하였다. 또한 각종 단백질 분해효소에 의해 활성을 상실함으로써 본 연구에서 정제한 항균 물질이 단백질성 물질임을 확인할 수 있었으며 30% ammonium sulfate 침전과 $C_{18}$ chromatography를 통하여 bacteriocin을 정제 할 수 있었다. Tricine-SDS-PAGE에 의해 bacteriocin의 분자량을 약 3.4 kDa으로 추정하였으며, 지시균의 생육 저지환의 위치가 bacteriocin band와 일치하였다. 정제된 bacteriocin으로부터 분석한 N-terminal 아미노산 부분 서열은 $NH_2$-ILLEELNV로 나타났다.

• The Korean Journal of Ecology
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• 제22권1호
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• pp.45-50
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• 1999

김치 발효 초기에 bacteriocin 생성 유산균을 분리하고자 하였다. 분리 유산균은 형태, 배양 및 생리학적인 특징과 16S rDNA의 부분적인 염기서열로부터 Lactococcus lactis로 동정되었다. 분리균주가 생성한 bacteriocin은 Listeria monocytogenes, Staphylococcus aureus와 같은 그람 양성 병원성 세균과 몇몇 유산균에 대해 항균활성이 있었고, 그람음성균인 Yesinia에는 활성이 없었다. bacteriocin의 활성은 protease, protease ⅩⅣ, a-chymotrypsin과 pepsin에 대해서 활성이 소실되었으나, lipase, trypsin, lysozyme에 대해서는 활성이 유지되었다. bacteriocin의 활성은 pH 2∼11에서 안정적이며 l00℃에서 10분간 열처리시에도 변하지 않았다. 따라서 L. monocytogenes는 발효초기에 L. lactis에 의하여 억제될 수 있다.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.101-108
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• 1997

A lactic acid bacterium LAB3113, isolated from traditionally fermented Kimchi was found to produce bacteriocin whose activity was very specific toward lactobacilli and not effective against any other bacteria. Lactobacilli affected by the inhibitory substance included Lactobacillus delbrueckii-lactis, L. johnsonii, L. gsseri, and L. curvatus. Based upon biochemical and physiological characteristics, LAB3113 was classified as Lactococcus lactis, and its bacteriocin was named as lactococcin K3113. Lactococcus lactis. LAB3113 produced bacteriocin at th early stage of growth and the concentration of the bacteriocin did not decrease even after alt stationalry phase. Optimal temperature of bacteriocin production was $25^{\circ}C$ at the initial pH 7.0. Partially purified lactococcin K3113 was completely inactivated by protease, but not affected by lipase, lysozyme and RNase. The bacteriocin was very heat-stable even after autoclaving for 20 min. It was also stable in pH changes, an was not affected by th presence of solvents. lacotococcin K3113 appeared to act in bactericidal mode against L. delbrueckii-lactis ATCC4797. Molecular weight of lactococcin K3113 was calibrated as 10,500 dal by SDS-PAGE an activity staining. Lactococcus lactis LAB3113 had four residential plasmids of 3.7kb, 11.2kb, 15.5kb, and 48kh in molecular sizes. Plasmid profile analysis of mutant strain revealed that 15.5 kb plasmid was re-sponsible for the production of lactococcin K3113 and its immunity to the bacteriocin.

• 한국축산식품학회지
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• 제22권2호
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• pp.164-171
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• 2002

박테리오신을 생산하는 9종의 유산균 배양액으로부터 ammonium sulfate를 첨가하여 제조된 각각의 조박테리오신을 혼합하여 복합박테리오신용액을 제조하였다. 복합박테리오신의 항균 활성은 단일 박테리오신보다 우수하였으며 항균 범위 또한 넓어짐을 알 수 있었고 단일 박테리오신에 대하여 저항성을 나타내는 Listeria monocytogenes의 생육을 저해하는 것으로 나타났다. 또한, 복합박테리오신은 pH와 열에강한 안정성을 보여 식품 가공 중에도 이용이 가능한 것으로 나타났다. 복합박테리오신을 프랑크소세지, 모짜렐라 치즈 및 돈육등심근에 첨가한 후 저장기간별 일반세균수의 변화를 조사한 결과, 대조구에 비해 유의적인 감소현상을 나타내었고 저장 28일 경과 후에는 모든 식품에서 1/10 또는 1/100 정도로 식품내 총세균이 억제되었다. 또한, 저장기간 중 VBN의 함량을 조사한 결과 돈육등심근과 모짜렐라 치즈의 경우 14일 이후부터 박테리오신 처리구가 대조구에 비해 유의적으로 낮은 수치를 보여주었다.

• 한국식품위생안전성학회지
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• 제33권6호
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• pp.516-520
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• 2018

박테리오신은 미생물이 생산하는 단백질성의 항균물질이다. 본 연구에서는 Enterococcus faecium CJNU 2008 균주로부터 생산되는 박테리오신에 대한 일부 특성을 규명하였다. 부분 정제 박테리오신은 열처리($100^{\circ}C$ 30분, $121^{\circ}C$ 15분) 및 유기용매(메탄올, 에탄올, 아세톤, 아세토니트릴, 클로로포름)에 대한 안정성이 우수하였으며 효소처리의 경우 Lipase와 ${\alpha}-amylase$에 대해서는 안정하였으나 Protease 처리에서 활성이 소실되었다. 이는 E. faecium CJNU 2008균주가 생산하는 항균물질이 단백질성의 박테리오신임을 추가적으로 증명하는 것이다. 병원성 세균인 Listeria monocytogenes 균주를 지시균으로 사용했을 때 박테리오신은 살균(bactericidal)의 작용양상을 보였다. Tricine-SDS-PAGE를 이용한 박테리오신의 분자량은 6.5 kDa 이하로 확인되었다. 부분 정제된 박테리오신을 이용하여 HPLC법을 활용한 정제를 수행하였으며 크로마토그램 상에서 단일 피크를 얻었을 수 있었다. 앞으로 정제된 박테리오신은 생화학적 분석 등에 활용할 계획이다.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.270-277
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• 1996

A bacteriocin-producing strain, DU-0608, was isolated from Kimchi and identified as Leuconostoc mesenteroides subsp. mesenteroides. The bacteriocin from isolate was inhibitory against Listeria monocytogenes, Micrococcus luteus and several strains of lactic acid bacteria. The bacteriocin was inactivated by pepsin, trypsin, $\alpha$-chymotrypsin, protease, $\alpha$-amylase and lipase, but not by catalase or by heating at $100^{\circ}C$ for 60 min. The molecular weight of the bacteriocin was estimated approximately 6 kDa. The inhibitory effect was bactericidal and rapid. Following treatment with isolate bacteriocin, cells of indicator strain (Lactobacillus sake JCM 1157) were damaged at the end regions of the cell wall, whereas the cells treated with nisin were damaged at many places around the cell wall.

• 한국식품위생안전성학회지
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• 제10권2호
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• pp.65-71
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• 1995

Bacteriocins from lactic acid bacteria have attracted much attention in recent years because of their useful worth in increasing safety and extending shelf life of foods. These substances show an inhibitory effect against some food spoilage bacteria and food-borne pathogens. The inhibitory effect fo the bacteriocin produces by lactic acid bacteria against Listeria monocytogenes(L. monocytogenes) was examined in this study. The culture supernatants of 5 kinds of bacteria among the 10 kinds of testes lactic acid bacteria had the inhibitory activity against Listeria sp., various Gram positive and Gram negative bacteria. Bacteriocin produced by Lactobacillus plantarum(Lact. plantarum) LMG 7945 was the most active toward L. monocytogenes. Bacteriocin production of the Lact. plantarum LMG 7945 cultured on MRS broth was increased late logarithmic phase over early stationary phase. This bacteriocin was stable at heat treatment and acidic pH relatively; The activity was retained after heating at 121$^{\circ}C$ for 15min and was active in the pH range of 2~4 but was lost above pH 5.

• Journal of Microbiology and Biotechnology
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• 제10권4호
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• pp.539-543
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• 2000

A new bacteriocin, named lacticin 10790, was purified from Lactococcus lactis subsp. cremoris KFCC 10790 by sequential adsorption, immobilized metal-affinity, cation-exchange, and $C_{18}$ reverse-phase chromatographies. The molecular mass of the bacteriocin was estimated to be between 3,000 and 3,500 Da. Lacticin 10790 showed a broad antimicrobial spectrum against many gram-positive bacteria. The bacteriocin was stable to heat and in the pH range between 2 and 6. Lacticin 10790 was destroyed by digestion with proteases and exhibited a bactericidal mode of action. An amino acid composition analysis of purified lacticin 10790 revealed a high concentration of hydrophobic amino acids. The N terminus of the bacteriocin was found to be blocked, upon analysis by Edman degradation. The results suggest that lacticin 10790 is a class I bacteriocin.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.522-530
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• 1994

Bacteriocin-producing lactic acid bacteria, Lactococcus sp. HY 449, was isolated from dairy products. Using response surface methodology, the various concentrations of medium compo- nents (tryptone, glucose, yeast extract, tween 80, and initial pH) were tested to find the optimum conditions for maximum bacteriocin production and growth of Lactococcus sp. HY 449. Central composite design was used to control the concentrations of medium components in the experiment. Bacteriocin production and cell growth of Lactococcus sp. HY 449 were most affected by glucose and yeast extract. Estimated optimum growth conditions of Lactococcus sp. HY 449 were as follows; tryptone 1.08%, glucose 1.129%, yeast extract 0.674%, tween 80 0.11%, and initial pH 7.19. Also estimated optimum conditions for bacteriocin production were tryptone 0.937%, glucose 1.108%, yeast extract 0.163%, tween 80 0.09%, and initial pH 6.98.