• Life and Agrochemicals
• /
• s.248
• /
• pp.24-27
• /
• 2009

식품위해 요인은 여러 가지이지만, 이에 대한 인식도 사회 문화적 환경에 따라 차이가 크다. 우리나라는 농약과 식품첨가물을, 미국은 병원성 미생물과 비만, 당뇨 등과 같은 영양학적 불균형을 가장 위험한 요인으로 인지하고 있었다. 식품안전은 이제 선택사항이 아닌 필수사항이다.

• Korean Journal of Food Science and Technology
• /
• v.43 no.1
• /
• pp.91-97
• /
• 2011

This study was performed to assess the microbiological quality and potential health risk of fresh-cut produce and organic vegetables sampled from supermarkets and department stores in Korea. A total of 96 samples comprised three types of fresh-cut produce (sprouts, mixed-vegetables, fruit) and three types of organic vegetables (lettuce, perilla leaf, green pepper). The samples were analyzed for total viable cell counts, coliforms, Enterobacteriaceae, Escherichia coli, Salmonella spp., Listeria monocytogenes, Vibrio parahaemolyticus, Bacillus cereus, and Staphylococcus aureus. The microbiological counts of fruit were very low. Sprouts were highly contaminated by total viable cell counts ($8.3{\pm}0.57$ log CFU/g), Enterobacteriaceae ($7.1{\pm}0.76$ log CFU/g), and coliforms ($4.9{\pm}0.40$ log MPN/g), and showed a high incidence level of B. cereus ($2.9{\pm}0.48$ log CFU/g). Of the fresh-cut produce analyzed, six (13.6%) mixed-vegetable salads were E. coli positive. S. aureus was detected in only one sprout sample and one mixed-vegetable salad, and its contamination levels were under 2 log CFU/g, which is appropriate for Korean standards (<3 log CFU/g) of fresh-cut produce. Of the organic vegetables, lettuces were highly contaminated by total viable cell counts ($6.4{\pm}0.74$ log CFU/g), Enterobacteriaceae ($5.7{\pm}0.98$ log CFU/g), and coliforms ($3.7{\pm}1.72$ log MPN/g). Two (13.6%) organic lettuce and one (7.1%) perillar leaf sample were E. coli positive, and S. aureus was detected in one lettuce and two perilla leaf samples. Salmonella spp., Vibrio parahaemolyticus, and Listeria monocytogenes were not detected in any of the fresh-cut produce or organic vegetables analyzed.

• Korean Journal of Microbiology
• /
• v.49 no.1
• /
• pp.51-57
• /
• 2013

As facilities and equipments for learning activities in college campuses are handled by mass public, their contact surfaces may function as major routes of cross-infection of microbial pathogens. However, unlike items in cafeteria which is the typical target for campus hygiene, those surfaces are not under regular surveillance or sanitary maintenance. In this study, I made a quantitative comparison of the risk of being exposed to microbial pathogens from use of learning facilities such as classrooms and library to the risk from use of cafeteria, for about 1,500 students in a college. Regarding total coliforms as surrogate model of bacterial pathogens, exposure rates were estimated for each item in learning facilities and cafeterias by devising deterministic exposure algorithms based on bacterial abundance, contract rates and transfer rates. The exposure rate in cafeterias was 1.0 CFU/day while learning facilities imposed the rate of 0.5 CFU/day, which reaches a half of the exposure rate in cafeterias. However, 70% of students were exposed more in learning facilities than cafeteria because individuals had different frequencies in using cafeteria. Based on the results, some human-contact surfaces of learning facilities, including elevator buttons, may require regular sanitary maintenance. An efficient sanitary maintenance considering seasonality in diversity of pathogens involved with cross-infections is suggested besides improvement of personal hygiene among students.

• Korean Journal of Microbiology
• /
• v.53 no.4
• /
• pp.323-325
• /
• 2017

Pectobacterium carotovorum subsp. actinidiae KKH3 is an Enterobacteriaceae bacterial pathogen that infects kiwi plants, causing canker-like symptoms that pose a threat to the kiwifruit industry. Because the strain was originally isolated from woody plants and possesses numerous plant cell wall-degrading enzymes, this draft genome report provides insight into possible bioconversion applications, as well as a better understanding of this important plant pathogen.

• Journal of Korean Society of Water and Wastewater
• /
• v.33 no.5
• /
• pp.379-388
• /
• 2019

Chlorination and UV illumination are being widely applied to inactivate a number of pathogenic microbials in the environment. Here, we evaluated the inactivation efficiency of individual and combined treatments of chlorination and UV under various aqueous conditions. UV dosage was required higher in waste water than in phosphate buffer to achieve the similar disinfecting efficiency. Free chlorine generated by electrolysis of waste water was abundant enough to inactivate microbials. Based on these, hybrid system composed of sequential treatment of electrolysis-mediated chlorination and UV treatment was developed under waste water conditions. Compared to individual treatments, hybrid system inactivated bacteria (i.e., E. coli and S. typhimurium) and viruses (i.e., MS-2 bacteriophage, rotavirus, and norovirus) more efficiently. The hybrid system also mitigated the photo re-pair of UV-driven DNA damages of target bacteria. The combined results suggested the hybrid system would achieve high inactivation efficiency and safety on various pathogenic microbials in wastewater.

• Korean Journal of Microbiology
• /
• v.37 no.4
• /
• pp.305-311
• /
• 2001

Antifungal bacterium, Bacillus subtilis YS1 was isolated from Yusong hot spring showed broad antifungal spectrum against 12 kinds of plant pathogenic fungi and Candida albicans, animal pathogen. From the gamma($Co^{60}$) radiation sensitivity test, $D_10$ value was 2.08 kGy and it survived above 20 kGy of radiation dose. Several mutants were induced by gamma radiation. Among them, YS1-1009 mutant showed resistance against tebuconazole of herbicide, increased activity against Botryoshaeria dothidea and ligninase activity. YS67 mutant was antifungal deficient auxotrophic mutants(trp-pro-or arg-ura-). From this results, it suggested that gamma irradiation could be useful method for mutant induction.

• The korean journal of orthodontics
• /
• v.36 no.4
• /
• pp.263-274
• /
• 2006

Objective: The purpose of this study was to evaluate clinical and microbiological changes in periodontal tissue around the banded molars after debanding. Methods: This study included 17 young adult patients treated with fixed orthodontic appliances including bands on the last molars more than 1 years. Probing depth and bleeding frequency were measured and plaque samples were collected from the last banded molars in all quadrants of each patient. All the data were collected immediately after debanding and 4 weeks after debanding. Results: Using polymerase chain reaction based on 16S rDNA, the presence of Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola was detected. After debanding, probing depth, bleeding frequency, and prevalance of periodontopathogens were reduced. Probing depth and bleeding frequency were most decreased in the buccal site of the mandibular left molar and were least decreased in the lingual site of the maxillary right molar. Conclusion: The results of this study indicated that proper management of oral hygiene after debanding can recuperate unfavorable periodontal condition caused by orthodontic treatment.

• The Journal of the Korean Society for Microbiology
• /
• v.11 no.1
• /
• pp.23-26
• /
• 1976

The authors identified sixteen Shigella cultures, which were three cultures of subgroup A, ten cultures of subgroup B, three cultures of subgroup D and none of cultures belnoging to the subgroup C was detected as it was in previous year.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
• /
• 2004.05a
• /
• pp.206-210
• /
• 2004

본 연구는 국내 조건에서 살라미를 생산하였을 때 현행 국내 육제품의 위생 기준을 만족시킬 수 있는지 여부와 살라미 저장 중 미생물학적 품질 변화를 살펴보기 위하여 실시되었다. 살라미 원료육에서는 Staphylococcus aureus와 대장균군이, 그리고 살라미 제품 중 한 시료에서 Clostridium perfringens가 검출되었다. 살라미의 저장 중 냉장온도($10^{\circ}C$)보다 실온($25^{\circ}C$)에서 균수의 감소가 두드러졌다. 제품의 저장 중 대장균군은 발견되지 않았다. 종합적으로 판단해 볼 때 살라미에서의 병원성 미생물에 대한 음성 기준을 만족시키기는 현실적으로 어렵다고 판단되므로 관련 기준의 완화가 요구된다.

• Korean Journal of Microbiology
• /
• v.45 no.2
• /
• pp.126-132
• /
• 2009

Legionella spp. is the causative agent of Legionellosis, which induces a potentially fatal form of pneumonia. With a concentrated performance during the summer of 2008, we secured 73 isolates from the water systems of 25 wards in Seoul. We analysed serotypes, pathogenic genes (Dot/Icm), and patterns of pulsed-field gel electrophoresis (PFGE) in an attempt to confirm relationships among them. Different from the previous year's pattern (2007), among the isolates, 69 were Legionella pneumophila and 4 were Legionella spp. The serotype distribution of Legionella pneumophila was sg1 43, sg6 9, sg5 8, sg3 8, and sg2 1. The serotype for the 4 Legionella spp. was Legionella nautarum. Most of the Legionella pneumophila had several pathogenic genes. On the other hand, the 4 Legionella spp. were defective in pathogenicity in genomic terms. The PFGE patterns of the serotypes showed a tendency for diversity of Legionella pneumophila and a close correlation with genetic pathogenicity.