• 한국식품과학회지
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• 제36권3호
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• pp.501-506
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• 2004

생식제품의 미생물학적 안전성을 확보를 위한 기초 자료로 활용하고자 생식제품 및 제조 공정 중에 있어서 Bacillus cereus, Clostridium perfringens, Staphylococus aureus 등 식중독세균을 중심으로 한 자연 환경 유래 위해미생물의 분포 및 주 오염공정을 조사하였다. 생식 원료 중 위해미생물의 검출율이 높은 원료는 주로 곡류이었으며, 원료를 일반수도수로 세척하고 동결건조 하여도 위해미생물은 완전히 제거되지 않아 원료에 대한 비가열살균 대책이 필요할 것으로 사료된다. 한편 최종제품의 위해미생물의 검출율이 원료보다 높게 나타나 제조공정 중 미생물 오염이 증가하는 것을 알 수 있었으며 위해미생물은 원료의 1차 분쇄 후 공정이 진행됨에 따라 증가하였고, 특히 외주분말(하청공장에서 원료를 세척, 건조, 분쇄한 것)을 혼합한 후 균수가 급속히 증가하였다. 공중부유균은 분쇄실과 혼합실에서 많이 검출되었으며, 생식 제조 공정에 사용되는 기계 및 기구에서도 위해미생물이 검출되어 공중부유균과 기계 및 기구의 오염, 그리고 기계에 끼여 있는 분말 찌꺼기가 제조공정 중 생식의 미생물 오염 원인이라는 것을 알 수 있었으며, 따라서 공중부유균의 살균대책 및 하청공장의 철저한 위생관리가 요구되며, 분쇄기 및 혼합기의 정기저인 소독 및 살균이 필요 할 것으로 사료된다.

• 한국어병학회지
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• 제17권1호
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• pp.39-55
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• 2004

감초외 48종의 천연 생약재로 부터 열수 및 알콜 추출액을 제작하여 19 균주 어병 세균을 대상으로 항균력을 조사한 결과, 알콜 추출액은 22종, 열수 추출액은 16종이 어병 세균에 대하여 항균력을 나타내며 이 중 13종의 생약재는 알콜 및 열수 추출액 모두 8 mm이상의 저지대를 나타내어 항균력이 있는 것으로 나타났다. 열수 추출물에서 항균력을 나타내는 약재 중 그람 음성균에 감수성이 양호한 약재는 저지대 8 mm 이상을 나타내는 애엽, 개옻나무, 연교, 지유, 파엽, 대황 및 황금이었으며, 그람 양성균에 항균력이 양호한 약재는 삼지구엽초, 육계 및 보골지 등 이었다. 그리고 오매, 황련, 계혈등, 상백피, 오배자 및 오미자는 저지대가 8mm 이상으로 그람 음성, 양성균 모두에 항균력이 있었다. 알콜 추출물중에서 그람 음성균에 항균력을 나타내는 것은 백작약, 오매, 선모 및 황금 등으로 저지대가 8mm 이상으로 측정되었으며, 그람 양성균에 항균력을 나타내는 것은 감초, 계혈등, 단삼, 상백피, 육계 및 보골지 등으로 저지대가 8mm이상이었다. 또한 그람 음성, 양성균에 모두 8mm 이상의 저지대를 나타내는 것은 애엽, 개옻나무, 황련, 지유, 오배자 및 오미자 등이었다. 그러나 이 중에서 오배자 열수 추출물의 어병 세균에 대한 발육 저지대가 32 mm로 그람 음성, 양성균 모두에 가장 뛰어난 항균력을 나타내어 다른 생약재와는 다른 광범위 생약재인 것으로 나타났다. 애엽, 황금, 지유, 오매, 황련 및 오배자 열수․알콜 추출물은 tetracycline(30$\mu{g}$)에 내성을 나타내는 균주에 감수성을 나타내었다.

• 생명과학회지
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• 제32권6호
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• pp.438-446
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• 2022

꽃은 특유한 모양, 색, 향, 맛으로 인한 시각적, 후각적 관능성이 우수하다. 최근에는 식용 꽃을 건조한 후 열수로 우려내는 침출차가 사회적 관심을 받고 있으며, 식용꽃을 이용한 기능성 식의약품 소재 개발도 진행되고 있다. 그러나 현재까지 건조꽃차의 유해 미생물, 중금속 및 잔류농약에 대한 위해성 평가는 거의 이루어진 바 없으며 농산물과 달리 건조꽃차에 대한 안전성 규격도 마련되어 있지 않다. 본 연구에서는 시판 건조꽃차의 유해 미생물, 중금속 및 잔류농약 오염도를 평가하였다. 먼저 유해 미생물 오염도 평가에서 23종 꽃차 시료 모두에서 대장균군 및 리스테리아균은 검출되지 않았다. 그러나 갈화, 캐모마일꽃, 아카시아꽃, 진달래꽃, 달맞이꽃, 유채꽃, 벚꽃의 경우 3.24~3.85 Log CFU/g의 일반세균이 검출되었으며, 황색포도상구균도 23종 꽃차 중 11종에서 검출되었다. 살모넬라균 역시 23종 꽃차 중에서 8종에서 검출되어 시판 꽃차의 유해 미생물 관리가 필요함을 확인하였다. 한편 대부분의 꽃차에서는 Pb, Cd, Co, Cr, Cu, Ni 및 As 유해 중금속은 검출되지 않았으나, 원추리꽃차에서만 0.08 ppm의 Pb가 검출되었다. 따라서 시판 꽃차에서 별도의 중금속 위해는 없을 것으로 판단된다. 건조꽃차의 경우 일부 꽃에서 잔류농약이 검출되었으나 극미량(0.01~0.08 ppm)으로 유해성은 없으리라 판단되었으며, 다만 국화꽃차에서 검출된 chlorpyrifos (0.215 ppm)의 경우 잠재적 위해 가능성이 인정되었다. 본 연구 결과는 건조꽃차의 잔류농약기준 설정이 필요하며, 식용꽃차의 안전성 확보를 위해 식용꽃차와 농약 사용이 허용되는 관상용 꽃의 엄격한 재배 구분이 필요하며, 꽃의 수확, 가공, 유통 단계에서 미생물적 오염 방지 노력도 필요함을 제시하고 있다.

• Safety and Health at Work
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• 제11권4호
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• pp.517-525
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• 2020

Background: The study was planned to show the status of indoor microorganisms and the status of the reduction device in the military dog clinic. Methods: Airborne microbes were analyzed according to the number of daily patient canines. For identification of bacteria, sampled bacteria was identified using VITEK^®2 and molecular method. The status of indoor microorganisms according to the operation of the ventilation system was analyzed. Results: Airborne bacteria and fungi concentrations were 1000.6 ± 800.7 CFU/m³ and 324.7 ± 245.8 CFU/m³. In the analysis using automated identification system, based on fluorescence biochemical test, VITEK^®2, mainly human pathogenic bacteria were identified. The three most frequently isolated genera were Kocuria (26.6%), Staphylococcus (24.48%), and Granulicatella (12.7%). The results analyzed by molecular method were detected in the order of Kocuria (22.6%), followed by Macrococcus (18.1%), Glutamicibacter (11.1%), and so on. When the ventilation system was operated appropriately, the airborne bacteria and fungi level were significantly decreased. Conclusion: Airborne bacteria in the clinic tend to increase with the number of canines. Human pathogenic bacteria were mainly detected in VITEK^®2, and relatively various bacteria were detected in molecular analysis. A decrease in the level of bacteria and fungi was observed with proper operation of the ventilation system.

• 식물병과 농업
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• 제5권1호
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• pp.41-45
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• 1999

Bacterial population densities on soybean pods from Chungnam province ranges 105~106 CFU/$\textrm{cm}^2$, whereas those of bacteria causing sprout rot ranged 0~103 CFU/$\textrm{cm}^2$. Erwinia chrysanthemi, Xanthomonas campestris pv. glycines, Staphylococcus sp., and Micrococcus sp. were identified as pathogenic bacteria causing soybean sprout rot. The population density of X. campestris pv. glycines was higher than those of other bacteria.

• Journal of Dairy Science and Biotechnology
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• 제39권2호
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• pp.51-62
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• 2021

Escherichia coli are the predominant facultative bacteria found in the gastrointestinal tract of animals and humans. Some strains of E. coli that acquire virulence factors and cause foodborne and waterborne diseases in humans are called pathogenic E. coli and can be divided into five pathotypes according to the virulence mechanism: EAEC, EHEC, EIEC, EPEC, and ETEC. Although selective media have been developed to detect E. coli, distinguishing pathogenic strains from non-pathogenic ones is difficult because of their similar biochemical properties. Therefore, it is very important to find a new and effective diagnostic method to identify pathogenic E. coli. With recent advances in molecular biology and whole genome sequencing, the use of polymerase chain reaction (PCR) is increasing rapidly. In this review paper, we provide an overview of pathogenic E. coli and present a review on PCR detection methods that can be used to diagnose pathogenic E. coli. In addition, the possibility of real-time PCR incorporating IAC is introduced. Consequently, this review paper will contribute to solving the current challenges related to the detection of pathogenic E. coli.

• Journal of Microbiology and Biotechnology
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• 제30권2호
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• pp.287-295
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• 2020

The differences between luminal microbiota (LM) and mucosal microbiota (MAM) were little known, especially in duodenum. In this study, LM and MAM in colon and duodenum of mice were investigated through 16S rRNA high-throughput sequencing. The lowest bacterial diversity and evenness were observed in duodenal LM (D_LM), followed by duodenal MAM (D_MAM). Meanwhile, the bacterial diversity and evenness were obviously increased in D_MAM than these in D_LM, while no significant difference was observed between colonic MAM (C_MAM) and colonic LM (C_LM). PCoA analysis also showed that bacterial communities of LM and MAM in duodenum were completely separated, while these in colon overlapped partly. The ratio of Firmicutes to Bacteroidetes (F/B) in D_MAM was significantly higher than that in D_LM. Lactobacillus was largely enriched and was the characteristic bacteria in D_LM. The characteristic bacteria in D_MAM were Turicibacter, Parasutterella, Marvinbryantia and Bifidobacterium, while in C_LM they were Ruminiclostridium_6, Ruminiclostridium_9, Ruminococcaceae_UCG_007 and Lachnospiraceae_UCG_010, and in C_MAM they were Lachnospiraceae_NK4A136, Mucispirillum, Alistipes, Ruminiclostridium and Odoribacter. The networks showed that more interactions existed in colonic microbiota (24 nodes and 74 edges) than in duodenal microbiota (17 nodes and 29 edges). The 16S rDNA function prediction results indicated that bigger differences of function exist between LM and MAM in duodenum than these in colon. In conclusion, microbiota from intestinal luminal content and mucosa were different both in colon and in duodenum, and bacteria in colon interacted with each other much more closely than those in duodenum.

• 치위생과학회지
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• 제18권1호
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• pp.18-23
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• 2018

Propolis has been used as a natural remedy in folk medicine worldwide. The antibacterial, antiviral, antifungal, and antiprotozoal aspects of its antimicrobial properties have been widely investigated. However, few studies focused on its applications in dentistry. Many dental diseases are related to various microorganisms in the oral cavity. In this study, we assessed the antimicrobial activity of Korean propolis extract, collected from 6 different regions, on oral pathogenic microorganisms. The propolis samples, collected from 6 different regions (P1: Uijeongbu, P2: Ansan, P3: Hongcheon, P4: Iksan, P5: Gwangju, and P6: Sangju), were dissolved in ethanol at two different concentrations (10 and 50 mg/ml). Three oral bacteria (Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis) and one fungus (Candida albicans) were activated in general broth for 24 hours. Microorganisms were diluted and spread onto agar plates, onto which sterilized 6 mm filter papers with or without each propolis sample were placed. After 24 hours of incubation, clear zones of inhibition were observed. All tests were performed in triplicate. The propolis samples showed significant antibacterial and antifungal activity on oral pathogenic microorganisms; in addition, low-concentration groups showed outstanding antimicrobial efficacy on the 4 different microorganisms. Among the samples, P6 had significantly higher antibacterial activity than that of the others against three different bacteria. In particular, a high concentration of P6 showed a significant antifungal effect. In conclusion, we confirmed that Korean propolis has an inhibitory effect on oral pathogenic bacteria and fungi. Therefore, we suggest the possibility of developing oral medicine and oral care products based on Korean propolis.

• 대한영양사협회학술지
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• 제24권4호
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• pp.330-343
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• 2018

Recently, there has been a growing demand for natural preservatives because of increased consumer interest in health. In this study, we produced Lactobacillus rhamnosus cell-free supernatant (LCFS) and evaluated and compared its antimicrobial activity with existing natural preservatives against pathogenic microorganisms and in chicken breast meat contaminated with Escherichia coli and Staphylococcus aureus. Lactobacillus rhamnosus cell-free supernatant possessed 30 units of lysozyme activity and contained 18,835 mg/L of lactic acid, 2,051 mg/L of citric acid and 5,060 mg/L of acetic acid. Additionally, LCFS inhibited the growth of fourteen pathogenic bacteria, S. aureus, Bacillus cereus, Listeria monocytogenes, Vibrio parahaemolyticus, Listeria innocua, S. epidermidis, L. ivanovii, E. coli, Pseudomonas aeruginosa, Shigella sonnei, Shi. flexneri, Proteus vulgaris, Pseudomonas fluorescens, and Klebsiella pneumoniae. The antibacterial activity of LCFS was stronger than that of egg white lysozyme (EWL), Durafresh (DF) and grapefruit seed extract (GSE). Additionally, LCFS maintained its antimicrobial activity after heat treatment at $50^{\circ}C{\sim}95^{\circ}C$ and at pH values of 3~9. Moreover, LCFS inhibited the growth of E. coli and S. aureus in chicken breast meat. In conclusion, it is expected that LCFS, which contains both lysozyme and three organic acids, will be useful as a good natural preservative in the food industry.

• 대한수의학회지
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• 제46권3호
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• pp.255-261
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• 2006

Experimental animals have been used to biological and medical purposes and the animals must be, for these purposes, healthy and clean to microbial infection. However, the animals can be easily exposed to pathogenic microorganism via several routes. Of the routes, environmental conditions are the most important factors to keep the animals healthy and clean, especially air condition. Monitoring of air-condition has been required to keep the animal healthy and clean. However, any guideline is not available for experimental conditions with pigs. Therefore, the sampling times and points were compared in different conditions to establish an optimal protocol for monitoring of air borne bacteria. Tryptic soy agar(TSA), blood agar containing 5% defibrinated sheep blood and Sabraud dextrose agar(SDA) were used as media to capture total bacteria, pathogenic bacteria and fungi, respectively. Two methods, compulsive capture using an air-sampler and capturing fall-down bacteria were used to capture the microorganisms in the air. The points and time of capturing were different at each experiment. Air borne microorganisms were captured at three and five points in the open and closed equipments, respectively. Air was collected using an air-sampler for 1 min and 5 min and the agar plates as open status were left from 30 min to 2hr. At first, we monitored an experimental laboratory which dealt with several pathogenic bacteria and then, a protocol obtained from the investigation was applied to open or close experimental conditions with pigs. Number of bacteria was high from 10:00 to 15:00, especially on 13:30-15:30 but sharply decreased after 17:00. The tendency of the number of bacteria was similar between two methods even though the absolute number was higher with air sampler. Critical difference in the number of cells was observed at 5 min with air sampler and 2 hr with fall-down capturing method. However, 1 min with air sampler and 1 hr with fall-down capturing were the best condition to identify bacterial species collected from the air. Number of bacteria were different depending on the sampling points in closed condition but not in opened condition. Based on our results, a guide-line was suggested for screening air-borne microorganism in the experimental conditions with pigs.