• 생명과학회지
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• 제22권5호
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• pp.692-696
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• 2012

식품으로부터 유래되어 치명적인 질병을 유발하는 $Listeria$ $monocytogenes$는 다양한 지지체 위에 biofilm을 형성할 수 있다. 이러한 biofilm은 여러 가지 소독제나 살균과정으로부터 $L.$ $monocytogenes$의 생존력이나 저항성을 증가시켜 준다. 본 연구에서도 $L.$ $monocytogenes$는 다양한 배양용기에서 biofilm을 형성하였으며, BHI를 배지로 하여 $30^{\circ}C$에서 4일 동안 배양하였을 때 최대의 biofilm을 형성하였다. $L.$ $monocytogenes$의 biofilm의 형성에 미치는 김치의 효과를 살펴본 결과 김치를 첨가함에 따라 biofilm의 양이 줄어들기도 하고 늘어나기도 하여, 김치에 따라 다른 영향을 미치는 것으로 여겨졌으며, 이러한 결과는 $L.$ $monocytogenes$의 생육에 미치는 김치의 효과와는 차이가 있었다.

• 한국식품조리과학회지
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• 제16권5호
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• pp.379-384
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• 2000

길경중 물과 에탄올을 이용하여 얻은 추출물을 5종의 식중독세균(Listeria monocytogenes ATCC 15313, Staphylococcus aureus 196E ATCC 13565, Escherichia coli O157:H7 ATCC 43895, Salmonella typhimurium ATCC 13311, Yersinia enterocolitica)에 대하여 항균효과를 검색한 결과 Gram양성균인 L. monocytogenes에 대하여 물 및 에탄을 추출물 모두 MIC가 60$\mu\textrm{g}$/ml으로 극히 우수한 항균효과를 보여주었으며 항균효과가 높은 추출물의 열 안정성을 살펴보기 위하여 Listeria monocytogenes균 ATCC 15313, 19111 및 19113등 3종에 대하여 실험한 결과 길경 내 항균성물질은 121$^{\circ}C$ 에서 15분간 처리 시에도 항균효과가 나타남을 보아 열 안정성이 있는 것으로 나타났다. 또한 길경 추출물의 농도에 따른 항균효과를 실험한 결과 추출물의 농도가 500$\mu\textrm{g}$/m1일 때 Listeria monocytogenes균 ATCC 15313, 19111 및 19113 균 모두에 거의 안정된 항균효과를 가지고 있었으며 특히 Listeria monocytogenes ATCC 15313에 대하여 더욱 강한 항균효과를 보여주었다.

• 한국미생물·생명공학회지
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• 제25권5호
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• pp.442-447
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• 1997

To development food preservative, antimicrobial activities of Schizandra chinensis (SC) against Listeria monocytogenes Scott A, L. monocytogenes Brie I and L. monocytogenes ATCC 19111 were investigated. The growth of L. monocytogenes Scott A, L. monocytogenes Brie I and L. monocytogenes ATCC 19111 was inhibited apparently in Tryptic Soy Broth (TSB) containing 1% SC at 35$\circ$C and it was found that these had antibacterial effects against a broad spectrum of pathogenic bacteria such as S. aureus ATCC 29737, B. subtilis KCTC 1021, E. coli ATCC 11775. The growth of L. monocytogenes was also inhibited about 3 to 5 log$_{10}$ cycle by 0.1% of three fractions of the alcohol extract such as ether, ethyl acetate and butanol. Acidic, weakly acid and neutral fraction of ether fraction showed inhibitory properties against L. monocytogenes.

• 대한수의학회지
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• 제36권1호
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• pp.119-129
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• 1996

The present study was conducted to rapidly detect Listeria monocytogenes in raw milk. Specificity and sensitivity of polymerase chain reaction(PCR) technique, and direct PCR were examinded in raw milk, also were compared the calssical culture methods with PCR technique. This method used a pair of primers based on a unique region in the 16S rRNA sequence of L nomocytogenes. In the PCR specificity tests, each of the 10 strains of L monocytogenes tested gave a single 70-bp band. But the other six Listera spp tested gave negative results. Results of the sensitivity tests showed that as few as 2 CFU of L monocytogenes in pure cultures could be detected with 16S rRNA-based primers, L-1 and L-2. In different PCR cycles, a PCR product was detected with $10^3$ cells of L monocytogenes from 25 cycles to 50 cycles and the concentration of PCR products was cycle-dependent. Raw milk samopes added L monocytogenes cells gave negative results. However, these samplers gave a single 70-bp band by pretreatment of pronase, and PCR products were detected with $10^1$ cells of L monocytogenes. To detemine the most sensitive culture protocol to use in conjunction with the PCR assay, raw milk samples were inoculated with L monocytogenes at concentrations ranging from 1 to $5.7{\times}10^4CFU/ml$. PCR assays from Listeria enrichment broth(LEB) containing raw milk samples added L monocytogene EGD could dtect 10 cells in pronase-pretreated samples without incubation, and 1 cell of L monocytogenes in both 12 hr and 24 hr incubation, respectively. Isolation raw of PCR assays was similar to that of classical culture methods, but required time for detection of L monocytogenes could remarkably be reduced compare to culture methods.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.196-199
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• 2003

We investigated the antagonistic effects of two lactococcal bacteriocins, nisin or lacticin NK24, on the growth and the survival of Listeria monocytogenes in vacuum or modified atmosphere-packaged ground beef, Ground beef was inoculated with approximately 3 log colony-forming units (CFU) of L. monocytogenes ATCC 15313 culture per gram of ground beef. Inoculated samples were blended with/without 100 AU/g nisin or lacticin NK24, and subsequently vacuum or modified atmosphere packed at 4$^{\circ}C$. Listeria in the bacteriocin-treated and control samples was subsequently isolated from both vacuum and modified atmosphere packs and enumerated as CFU on Listeria Isolation Agar medium. Microbial counts in ground beef treated with bacteriocin declined steadily, while those of non-treated beef samples increased steadily. The results obtained demonstrate that nisin inhibits the growth of L. monocytogenes more effectively than lacticin NK24 at 100 AU/g. The use of lactococcal bacteriocins, such as nisin or lacticin NK24, in vacuum or modified atmosphere packaging offers a promising approach for eliminating or reducing the risk of L monocytogenes contamination in ground beef.

• 한국동물위생학회지
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• 제23권4호
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• pp.341-348
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• 2000

Nowadays we continue to face challenges to the safety of our foods. It seems clear that contaminated meats provide the major route of listeria monocytogenes transmission from the environment to humans. L monocytogenes is the most important species associated with disease in humans among the listeria sp. The current incidence of symptomatic listeriosis caused by L monocytogenes is uncertain. Although the number of reports in the literature on listeriosis are increasing, it is likely that they are actually unrecognized or underreported because of a lack of awareness on the part of some laboratory workers who fail to isolate or identify these organisms. To get the information of sanitary development, we survey various meats (beef, pork, etc) in Kyongbuk area. Samples were collected from local meat shop at Kyongbuk area. Total sixty six case were isolated and identified from one hundreds and seven samples. L innocua was the most abundant in listeria sp. Among U isolates, the number of isolated L innocua was 43 (65.2%). The numbers of isolated L murrayi, L welshimeri, L monocytogenes and L seeligeri were 12(18.2%), 7(10.6%), 3(4.5%) and 1(1.5%), respectively, but L grayi, L iuanouii were not Isolated.

• 한국동물위생학회지
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• 제26권2호
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• pp.105-111
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• 2003

From February 2000 to December 2001, A total of 1,785 samples was taken from beef and pork carcasses in Seoul. Seven(0.69%) Listeria spp. were isolated from the 1,014 of beef carcasses, and five(0.65%) were isolated from the 771 of pork carcasses. The isolates were identified L monocytogenes by API listeria, and VIDAS LMO kit, serological test and PCR assay were preformed. A total 12 strains of L monocytogenes were isolated form samples tested and all of the strains were classified into serotype 1. PCR primers are selected to amplify a 520-base pair(bp) DNA fragment from the listeolysin O gene(hlyA) of Listeria monocytogenes. A 520-bp product was detected in PCR with DNA from L monocytogenes, but not from the other Listeria species tested.

• 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.

• 한국수산과학회지
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• 제36권3호
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• pp.193-197
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• 2003

Psychrotrophic characteristics of Listeria monocytogenes YM-7 showed similar growth at $8^{\circ}C$ as L. monocytogenes ATCC 15313. But it showed different growth pattern at $4^{\circ}C.$ Thus the isolated strain from the Patient can not grow at $4^{\circ}C,$ while L. monocytogenes ATCC 15313 grow slowly. Number of the injured cells of L. monocytogenes YM-7 was higher at $-3^{\circ}C$ than at $-18^{\circ}C$ in phosphate buffer solution. The rate of the injured cell was higher in the TSB (tryptic soy broth) medium than in phosphate buffer solution at $-3^{\circ}C$ and $-18^{\circ}C.$ When L. monocytogenes YM-7 stored at $-18^{\circ}C$ in homogenized fish muscle, the cell numbers decreased by 2-3 log cycles in 12 weeks.

• 대한수의학회지
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• 제45권3호
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• pp.359-367
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• 2005

This study was carried out to understand the contamination patterns of Listeria in pork processing plants. A total of 402 samples were collected from carcass, pork during processing, surfaces of equipment and environment, and 238 isolates of Listeria species were identified. L. innocua was found in 64.7% of the isolates, L. monocytogenes in 33.2%, and L. welshimeri in 2.1%. Random amplified polymorphic DNA (RAPD) analysis performed to investigate the origin and routes of Listeria contamination, showed 21 composite types of L. monocytogenes and 26 composite types of L. innocua. It was confirmed that Listeria contamination begins with contaminated incoming carcass and ever-present contaminants in the processing environments. The persistence and dissemination of the same strain of L. monocytogenes and L. innocua throughout the processing line revealed that the sanitation standard operating procedure should be implemented to minimize the risk of colonization in the workplace. Molecular subtyping of L. innocua allowed us to tracing the possibility of cross-contamination during processing.