• 한국축산식품학회지
• /
• 제39권6호
• /
• pp.1015-1020
• /
• 2019

Staphylococcus aureus is a representative pathogenic bacterium carefully controlled in the dairy industry because it causes bovine mastitis and thus, can enter the dairy chain. Furthermore, the emergence of multi-drug resistant S. aureus is a big problem. We previously isolated a Lactococcus lactis strain producing a bacteriocin that exhibited strong antimicrobial activity against S. aureus. In this study, we investigated the synergistic inhibition of S. aureus by the bacteriocin and a bacteriophage (SAP84) which is specific to the organism. The bacteriocin (12.5-100 AU/mL) inhibited the growth of S. aureus KCTC 3881 in a dose-dependent manner, as did the bacteriophage SAP84 (0.001-1 MOI; multiplicity of infection). Co-treatment with the bacteriocin (100 AU/mL) and the bacteriophage (0.1 MOI) significantly inhibited the growth of S. aureus compared to each treatment alone (bacteriocin or bacteriophage), indicating the two components showed synergistic inhibition of S. aureus. Therefore, the bacteriocin and bacteriophage combination can be used as a good strategy for controlling pathogenic bacteria.

• Journal of Microbiology and Biotechnology
• /
• 제12권6호
• /
• pp.936-942
• /
• 2002

When used in combination with organic acids, Pediococcus acidilactici K10 or its bacteriocin was effective in inhibiting Escherichia coli O157:H7 in vitro and in situ. P. acidilactici K10, a strain of bacteriocin-producing lactic acid bacteria (LAB), was previously isolated from kimchi in our laboratory, and the molecular weight of its bacteriocin was estimated to be around 4,500 Da by SDS-PAGE. Initially, P. acidilactici K10 and its bacteriocin could not inhibit E. coli O157:H7, when used alone. However, when they were used together with organic acids such as acetic, lactic, and succinic acids, they greatly inhibited E. coli O157:H7 in vitro. Based on these in vitro results, a real sample test with ground beef was conducted at $4^{\circ}C$ with acetic acid (0.25%) or lactic acid (0.35%) alone, and then in combination with P. acidilactici K10 (10^5 CFU/g of sample). Combined treatment of P. acidilactici K10 with lactic acid showed the most inhibitory effect: a 2.8-$log_{10}$-unit reduction of E. coli O157:H7 in ground beef during storage at $4^{\circ}C$. This result suggests that the combination of bacteriocin-producing P. acidilactici K10 and organic acids has great potential as a food biopreservative by inhibiting the growth of E. coli O157:H7.

• 한국식품위생안전성학회지
• /
• 제20권4호
• /
• pp.217-224
• /
• 2005

E.faecium MJ-14가 생산하는 박테리오신 30 BU/ML 처리에 의해 L. monocytogepes 균수는 0.6 log unit 감소 되었으나, 박테리오신 (30 BU/mL $65^{\circ}C$, 5분간 가열처리와 병용한 경우에는 약 2.7 log unit가 감소하였다. 박테리오신 30 BU/mL와 itric acid혹은 acetic acid $0.5\%$를 병용 처리한 경우에는 24시간 만에 초기균수가 각각 약 2 log unit와 3 log unit감소하였다. 박테리오신 30 BU/mL와 NaCl $8\%$를 병용 처리했을 때에는 박테리오신 단독 처리구보다 약 1 log unit더 감소되었다. 또한, 박테리오신 30 BU/mL단독 처리했을 때에 비해 sodium benzoate $500{\mu}g/mL$혹은 sodium lactate $1000{\mu}g/mL$와 각각 병용 처리하면 2 log unit가 더 감소되었으며, sodium nitrate $100{\mu}g/mL$와 potassium nitrate $100{\mu}g/mL$와의 병용 처리한 경우 박테리오신 단독 처리구에 비해 각각 3.5 log unit와 2 log unit이상 더 감소하였다. 한편, 탈지유에 E. faecium MJ-14의 박테리오신 300 BU/mL을 첨가한 경우 $4^{\circ}C$에서 24시간 만에 L. monocytogenes의 균수는 대조구에 비해 각각 약 1.5 log unit감소되었으며,돈육에 첨가한 경우 $-20^{\circ}C$에서 7일간 만에 대조구보다 약 2 log unit의 감소효과가 나타났다.

• Journal of Microbiology and Biotechnology
• /
• 제14권5호
• /
• pp.924-931
• /
• 2004

A bacteriocin-producing lactic acid bacterium, which strongly inhibited the Lactobacillus plantarum recognized as an important acid spoilage microorganism in kimchi fermentation, was isolated from kimchi. From morphological, physiological, sugar fermentation, biochemical tests, and l6S rDNA sequencing results, the isolate was identified as an Enterococcus sp. and designated as Enterococcus sp. K25. The bacteriocin produced by Enterococcus sp. K25 inhibited several Gram-positive bacteria, including Lb. plantarum, whereas it did not inhibit Gram-negative bacteria and yeasts. Optimal temperature and pH for the bacteriocin production were $25^\circ{C}$ and 5.5, respectively. Enterococcus sp. K25 was applied to kimchi manufacturing alone and together with other preservatives (i.e., chitosan and fumaric acid). In addition, growth of lactic acid bacteria, pH, and titratable acidity (TA) were measured during aging at $5^\circ{C}$ and $10^\circ{C}$. Inoculation of Enterococcus sp. K25 together with fumaric acid showed the most synergistic effect on extension of kimchi shelf-life. Compared to control (no addition), the treatment prolonged the kimchi shelf-life up to 6 days, whereupon the eight-point TA value recognized as the edible limit was reached.

• Journal of Microbiology and Biotechnology
• /
• 제11권5호
• /
• pp.831-837
• /
• 2001

Pediocin K1, a bacteriocin produced by Pediococcus sp. K1 isolated from Korean traditional fermented flatfish, inhibited certain strains of Lactobacillus, Streptococcus, and Listeria monocytogenes. Pediocin K1 was found to be stable at $90^{\circ}C$ for 30 min. Among the organisms tested, Listeria monocytogenes was the most sensitive to pediocin K1 and was completely killed when the initial inoculum size of L.monocytogenes cells was equal to or less than $10^3 CFU/ml$. The degree of inibition of Listeria monocytogenes by pediocin K1 increased 10-fold on the addition of citric acid ($0.2\%$) to the medium, thereby showing the synergistic effect of citric acid. Listeria monocytogenes cells resistant to pediocin K1 appeared at a frequency of about $10^-4$/cells. Once developed after exposure to pediocin K1, the resistant phenotype still persisted in the absence of pediocin K1 in successive cultures. This infers that resistance may be attributable to genetic change(s) in the resistant cells.

• Asian-Australasian Journal of Animal Sciences
• /
• 제30권2호
• /
• pp.211-220
• /
• 2017

Objective: The aim of the present study was to investigate the effect of yeast with bacteriocin and Lactobacillus cultures (mixture of Lactobacillus agilis BCRC 10436 and Lactobacillus reuteri BCRC 17476) supplements, alone or in combination, on broiler chicken performance. Methods: A total of 300, 1-d-old healthy broiler chickens were randomly divided into five treatment groups: i) basal diet (control), ii) basal diet+0.25% yeast (Saccharomyces cerevisiae) (YC), iii) basal diet+0.25% yeast with bacteriocin (BA), iv) basal diet+Lactobacillus cultures (LAB), and v) basal diet +0.25% yeast with bacteriocin+Lactobacillus cultures (BA+LAB). Growth performance, cecal microbiota, cecal fermentation products, and blood biochemistry parameters were determined when chickens were 21 and 35 d old. Results: The supplementation of YC, BA, and BA+LAB resulted in a significantly better feed conversion rate (FCR) than that of the control group during 1 to 21 d (p<0.05). The LAB supplementation had a significant effect on the presence of Lactobacillus in the ceca at 35 d. None of the supplements had an effect on relative numbers of L. agilis and L. reuter at 21 d, but the BA supplementation resulted in the decrease of both Lactobacillus strains at 35 d. The BA+LAB supplementation resulted in higher short chain fatty acid (SCFA) in the ceca, but LAB supplementation significantly decreased the SCFA at 35 d (p<0.05). All treatments tended to decrease ammonia concentration in the ceca at 21 d, especially in the LAB treatment group. The BA supplementation alone decreased the triacylglycerol (TG) concentration significantly at 21 d (p<0.05), but the synergistic effect of BA and LAB supplementation was required to reduce the TG concentration at 35 d. The YC supplementation tended to increase the plasma cholesterol at 21 d and 35 d. However, the BA supplementation significantly decreased the cholesterol and low density lipoprotein cholesterol level at 35 d. In conclusion, the BA+LAB supplementation was beneficial to body weight gain and FCR of broiler chickens. Conclusion: The effect of BA and LAB supplementation may be a result of the growth of lactic acid bacteria enhancement and physiological characterization of bacteriocin, and it suggests that the BA and LAB supplementation level or Lactobacillus strain selection should be integrated in future supplementation designs.

• 미생물학회지
• /
• 제45권1호
• /
• pp.41-47
• /
• 2009

메주에서 분리된 Enterococcus faecalis MJ-213이 생산한 박테리오신 용액과 유기산의 혼합 처리에 의한 Listeria monocytogenes KCTC 3569의 항균효과를 조사하였다. 박테리오신 256 BU/ml 단독 처리에 의한 L. monocytogenes KCTC 3569의 감소율은 약 32% 정도였으나, 박테리오신과 acetic acid 2.0%의 혼합 처리에 의해 약 80% 감소되었고, 혼합한 유기산 중에서 citric acid와 lactic acid 보다 acetic acid에 의해 더 높게 나타났다. 한편, acetic acid 1.5%와 박테리오신 128 BU/ml에 의해선 약 30% 정도 감소된 반면, 512 BU/ml와의 혼합 처리에 의해선 약 78% 정도 감소되었다. 또한 유기산과 박테리오신의 혼합처리시 L. monocytogenes KCTC 3569의 초기 균수가 3 log CFU/ml인 경우 7 log CFU/ml일 때보다 감소율은 무려 2배 이상 증가되어 초기 균수가 적을수록 항균효과는 더 크게 나타났다. L. monocytogenes KCTC 3569의 증식과정 중 유도기에 acetic acid와 박테리오신을 혼합 처리한 경우 박테리오신 단독처리 때 보다 흡광도는 약 절반 정도에만 머물렀다. 시판 돈육 내에 존재하는 L. monocytogenes KCTC 3569의 균수는 박테리오신 256 BU/ml 단독 처리한 경우 $4^{\circ}C$에서 60시간 동안 약 1 log CFU/ml 감소되었으나, acetic acid와 혼합 처리에 의해선 약 2 log CFU/ml 감소되었다. 한편 가열 처리 전후 박테리오신 용액의 항균 활성에는 거의 변화가 없었다.

• 미생물학회지
• /
• 제46권2호
• /
• pp.192-199
• /
• 2010

식중독균에 대하여 Enterococcus faecalis MJ-213이 생산하는 박테리오신과 소르빈산칼륨의 혼합처리에 의한 항균효과를 조사하였다. Staphylococcus aureus ATCC 6538에 대한 박테리오신의 MIC는 50 ${\mu}g$/ml, Salmonella enteritidis ATCC 13076에 대한 MIC는 100 ${\mu}g$/ml이었으나, 400 ${\mu}g$/ml의 농도 하에서도 Vibrio parahaemolyticus KCTC 2471의 증식억제 효과는 나타나지 않았다. S. aureus ATCC 6538과 S. enteritidis ATCC 13076 ($10^6$ CFU/ml)에 박테리오신 100 ${\mu}g$/ml 단독 처리 후 24시간 만에 초기 균수가 각각 약 4 log와 2 log cycle 감소되었고, 박테리오신 100 ${\mu}g$/ml와 소르빈산칼륨 100 ${\mu}g$/ml을 혼합 처리한 경우는 박테리오신만을 처리할 때 보다 유의적(p<0.05)으로 더 높은 항균효과가 나타났다. $121^{\circ}C$에서 15분간 가열한 박테리오신 단독처리에 의한 S. aureus과 S. enteritidis의 저해율은 각각 $9.36{\pm}0.58%$와 $3.71{\pm}0.24%$로 가열처리 하지 않은 박테리오신의 항균력 보다 크게 감소하였다. pH 조정하지 않은 박테리오신 단독 처리에 의한 S. aureus의 저해율($65.61{\pm}0.42%$)은 pH 6.0 혹은 8.0으로 조정한 박테리오신 처리구와 유의적인 차이가 없었으나, 그 외의 pH로 조정한 박테리오신의 항균력은 유의할 만한 수준으로 감소되었다. 박테리오신 활성은 ${\alpha}$-amylase와 lipase 처리에 영향을 받지 않았으나, protease II와 pepsin 처리에 의해선 활성이 거의 소실되었다. 또한 갈은 쇠고기 내에 접종된 S. aureus와 S. enteritidis의 균수도 박테리오신 단독처리시보다 소르빈산칼륨과 혼합처리에 의해 $4^{\circ}C$에서 저장하는 동안 유의적(p<0.05)으로 더 낮은 균수를 유지하였다.