안전 축산물 생산을 위한 사료공장에서의 HACCP적용

서근석,박용호,윤장원,신숙,주이석,장금찬 대한수의학회 1997 대한수의학회 학술대회발표집 Vol.1997 No.-

Evaluation of the HApS™ Method for the Enumeration of Aerobic Microorganisms and Coliforms in Retailed Meat Samples in Korea

박용호,서근석,김소현,임지연,배원기,권남훈,김지연,허문종 한국식품위생안전성학회 2001 한국식품위생안전성학회지 Vol.16 No.3

This study was designed to compare the effectiveness and applicability of the HApS (Hazard Analysis process System; HUKO, Seoul, Korea) based on Petrifilm^(TM)(3M, St. Paul, MN, USA) with the AOAC (the Association of Official Analytical Chemists) standard total aerobic count (TAC) method and coliform count (CC) method for meat products. The comparisons were carried out using 230 meat samples collected from various retailers: 80 pork samples, 80 chicken samples, and 70 beef samples. In the comparison of the correlation coefficient (r) between conventional method and HApS^(TM) method by a linear regression analysis, the correlation coefficients in total microorganism were 0.97767, 0.90712, and 0.95594 in pork, beef, and chicken samples, respectively. The correlation coefficients in coliform count were 0.82062, 0.94833, and 0.96839 in pork, beef and chicken samples, respectively. All the independent t-test on measun:ment values between conventional method and HApS^(TM) method represented no significant differences in the means between two methods at the 0.05 of significance level(α=0.05). Based on the high correlation between HApS^(TM) and the AOAC standard methods in the TAC and CC, it might be compatible to employ the HApS method to measure the microbial contamination in livestock products. HApS^(TM) method was simpler and less time-consuming in sample preparation and procedures faster than the conventional method. These results suggested that the HApS method could be substitute for the conventional methods in the analysis of microbial contamination measurement in meat products.

Development of Multiplex PCR for Detection of Vancomycin Resistant Enterococci and Epidemiological Application in Korea

Park, Yong Ho,Seo, Keun Seok,Yoo, Han Sang,Gwyther, M.J. 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.4

Vancomycin에 저항성을 나타내는 장구균(VRE)은 중요한 병원내 감염 병원균으로 등장하고 있으며 1989년 미국 CDC의 보고에 따르면 VRE에 의한 세균혈증과 심내막염의 감염율이 매우 빠른 속도로 증가하고 있다고 알려져 있다. 이러한 VRE의 축산동물 내에서의 등장은 avoparcin의 사용에 관련이 있을 것이라고 주장되어지고 있다. 본 연구에서는 4가지 형태의 VRE를 유도하는 유전자를 진단하고 구별할 수 있는 multiplex PCR법을 확립하였으며 이를 이용하여 avoparcin을 사용하였던 농장 및 사용하지 않은 농장으로부터의 VRE의 분리율 및 유전자형을 조사하였다. 70개소의 돼지 및 32개소의 닭 농장으로부터 1,091개의 분변 샘플을 수거하여 425주의 장구균을 분리하였으며 그 중 11주가 높은 농도의 vancomycin 저항성(64-256㎍/㎖)을 나타내었으며 PCR 조사결과 vanA, vanB 유전자를 확인할 수 있었다. 57주의 낮은 농도의 vancomycin에 저항성 3-8㎍/㎖)을 나타내는 VRE는 PCR 조사결과 vanC-1 또는 vanC-2의 유전자를 확인할 수 있었다. 국내의 높은 농도의 vancomycin에 저항성을 나타내는 VRE의 분리율(11/425, 2.58%)은 avoparcin을 사용하였던 다른 나라의 분리율(22/55 in England, 7% in Belgium)에 비해 현저히 낮은 것으로 조사되었다. 또한 분리주에 대한 유전적 연관성을 분석하기 위하여 rep-PCR법을 확립하였으며 이를 이용하여 8주의 동물유래 VRE와 31주의 사람유래 VRE의 rep-PCR 양상을 분석한 결과 사람유래 VRE의 경우 6개, 동물유래 VRE의 경우 한 개의 역학적으로 연관성이 있는 그룹이 관찰되었으며 사람유래 VRE의 동물유래 VRE간의 연관성을 관찰할 수 있었다. 결론적으로, 돼지 및 양계농장으로부터 11주의 high-level VRE가 분리되었으며, 이를 사람으로부터 분리된 VRE와 genotype 등을 비교 분석한 결과, 역학적으로 상관관계가 없는 것으로 확인되어 국내에서 동물사료첨가제로 쓰이는 avoparcin에 의한 vancomycin 항생제 유도는 인정되지 않았다. Vancomycin resistant enterococci (VRE) have emerged as an important nosocomial pathogen. Since 1989 the Center for Disease Control, United States, has reported a rapid increase in the incidence of enterococcal bacteremia and endocarditis infection by VRE. It was suggested that the use of avoparcin in animal husbandry was associated with the appearance of VRE. In this study a multiplex PCR method was established to detect and differentiate genotypes of enterococci which specifically amplify the four van genes encoding vancomycin resistance elements. The incidence rates and types of VRE from farms using or not using avoparcin was investigated using this method. From 1,091 animal fecal samples collected from 70 pig and 32 poultry farms, a total of 425 of enterococci were isolated. Of the isolates, 11 of the them showed a pattern of high-level vancomycin resistance (MIC: 64-256 ㎍/㎖) which was associated with the vanA or vanB gene. Fifty-seven isolates showed a pattern of low-level vancomycin resistance (MIC: 3-8 ㎍/㎖) associated with the vanC-1 or vanC-2 gene. The high-level VRE isolation rate in Korea (2.58%) was much lower than that of other countries (50% in England. 7% in Belgium) where avoparcin have been used. A repetitive extragenic palindromic PCR (rep-PCR) method was also established to determine genetic relatedness between animal and human VRE isolates. The repPCR pattern of 31 human VREs isolates with 11 animal isolates was compared. Human isolates generated five different types of group (Group Ⅱ to Ⅳ), whereas animal isolates generated only one group (Group Ⅰ). None of animal isolates had similar rep-PCR pattern of the human isolates. This result suggested that no genetic relatedness was in between animal and human VRE in Korea. In conclusion, the multiplex PCR and rep-PCR methods established in this study could be applied for detection of VRE and might be useful for the epidemiological investigations for their origins.

식육유래의 Staphylococcus aureus으로부터 산생되는 staphylococcal superantigens의 유전자형 분석

윤장원,정석찬,양수진,정병열,서근석,김소현,박용호,Yoon, Jang-won,Jung, Suk-chan,Yang, Soo-jin,Jung, Byong-youel,Seo, Keon-suk,Kim, So-hyun,Park, Yong-ho 대한수의학회 1998 大韓獸醫學會誌 Vol.38 No.3

Using the previous established multiplex PCR (mPCR), the presence of six kinds of staphylococcal superantigen (SAg) genes was investigated for nineteen Staphylococcus aureus isolates from the commercialized meat sources. As a result, only one isolate from pork among 19 S aureus isolates (5.3%) was confirmed as a potential SAg producer and harbored sec gene. The results in this study suggest that meat may not be major contagion of staphylococcal food poisoning (SFP) in Korea and that staphylococcal enterotoxin type C may be associated with the disease. Also, the mPCR method in this study can be a useful genotypic method which can overcome the typical disadvantages of conventional antibody-based methods due to antigenic homology, and furthur survey on food-borne S aureus isolates can provide the important epidemiological data for SFP in Korea.

포도상구균 장내 C 형 변이독소 (SEC mutant)의 면역원성에 대한 연구

장병선,주이석,문진산,서근석,양수진,김소현,박용호,Chang, Byoung-sun,Joo, Yi-seok,Moon, Jin-san,Seo, Keun-seok,Yang, Soo-jin,Kim, So-hyun,Park, Yong-ho 대한수의학회 2001 大韓獸醫學會誌 Vol.41 No.2

Mastitis is one of the most significant cause of economic loss to the dairy industry. Especially, Staphylococcus aureus is a major contagious mastitis-causing pathogen in dairy cattle. Because of its high transmission rate and resistance to antibiotic therapy, staphylococcal mastitis presents a constant threat to the dairy industry. Staphylococcal enterotoxin C(SEC) produced by S aureus has been known as one of superantigens which are able to stimulate a large proportion of T lymphocytes independently of their antigenic specificity. In this experiment, we have conducted preliminary studies with mice and lactating cows to evaluate the immunogenicity and safety of the experimental vaccine consists of SEC mutant antigen on controlling the bovine mastitis associated with S aureus infections. The average value of somatic cell counts in quarter milk, isolation rate of S aureus were consistently decreased in SEC-SER vaccinated groups, whereas antibody titers were highly increased in SEC-SER vaccinated groups. Peripheral blood were also collected from the lactating cows to determine the proportion of leukocyte subpopulation associated with humoral immunity(HI) and cell mediated immunity(CMI). Proportion of leukocyte subpopulation expressing $BoCD2^+$(total T lymphocyte), $BoCD4^+$(T helper cell), $BoCD8^+$(T cytotoxic/suppressor cell) and NonT/NonB lymphocyte which are involved in CMI in SEC-SER vaccinated groups were decreased for the initial stage after first vaccination and then increased from ten weeks after first vaccination maintaining elevated level till 14 weeks after vaccination. In contrast, proportion of monocyte, MHC class II and B lymphocyte which are associated with the production of primary immune response in SEC-SER vaccinated groups were increased for the initial period and then decreased from ten weeks after first vaccination. We present evidence that vaccination of SEC-SER mutant antigen in lactating cows induced a significant proliferation of bovine T lymphocytes. These results suggest that SEC-SER mutant antigen used in this experiment might be one of potential immunogen in developing innovative vaccine against bovine IMI associated with S aureus. Additional challenge trials should be carried out to evaluate substantial protection against S aureus under the commercial farm conditions.

식품 및 환경 , 기타 Bifidobacterium longum HYS001 균주의 Escherichia coli O157H7 과 Salmonella typhimurium DT104 장관 내 감염 예방효과 및 Vero Cytotoxin 중화효과

양수진(Soo Jin Yang),윤장원(Jang Won Yoon),서근석(Keun Seok Seo),구혜정(Hye Cheong Koo),김소현(So Hyun Kim),배형석(Hyoung Suk Bae),백영진(Young Jin Baek),박용호(Yong Ho Park) 한국미생물생명공학회 1999 한국미생물·생명공학회지 Vol.27 No.5

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