• Journal of Animal Science and Technology
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• v.64 no.3
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• pp.515-530
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• 2022

Sequence type (ST) 5 methicillin-resistant Staphylococcus aureus (MRSA) with staphylococcal cassette chromosome mec (SCCmec) type II (ST5-MRSA-II) and ST72-MRSA-IV represent the most significant genotypes for healthcare- (HA) and community-associated (CA) MRSA in Korea, respectively. In addition to the human-type MRSA strains, the prevalence of livestock-associated (LA) MRSA clonal lineages, such as ST541 and ST398 LA-MRSA-V in pigs and ST692 LA-MRSA-V and ST188 LA-MRSA-IV in chickens, has recently been found. In this study, clonotype-specific resistance profiles to cathelicidins derived from humans (LL-37), pigs (PMAP-36), and chickens (CATH-2) were examined using six different ST groups of MRSA strains: ST5 HA-MRSA-II, ST72 CA-MRSA-IV, ST398 LA-MRSA-V, ST541 LA-MRSA-V, ST188 LA-MRSA-IV, and ST692 LA-MRSA-V. Phenotypic characteristics often involved in cathelicidin resistance, such as net surface positive charge, carotenoid production, and hydrogen peroxide susceptibility were also determined in the MRSA strains. Human- and animal-type MRSA strains exhibited clonotype-specific resistance profiles to LL-37, PMAP-36, or CATH-2, indicating the potential role of cathelicidin resistance in the adaptation and colonization of human and animal hosts. The ST5 HA-MRSA isolates showed enhanced resistance to all three cathelicidins and hydrogen peroxide than ST72 CA-MRSA isolates by implementing increased surface positive charge and carotenoid production. In contrast, LA-MRSA strains employed mechanisms independent of surface charge regulation and carotenoid production for cathelicidin resistance. These results suggest that human- and livestock-derived MRSA strains use different strategies to counteract the bactericidal action of cathelicidins during the colonization of their respective host species.

• Journal of Food Hygiene and Safety
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• v.17 no.1
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• pp.31-35
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• 2002

According to food poisoning statistic data of 2000, the food poisoning outbreaks have occurred mainly by meat (27.9%), shellfish and its processed products (26.0%), and ready-to eat meals (24.0%) such as Kimbap and packed lunch boxes. The major causative flood poisoning bacteria were Salmonella spp. (35.6%), Staphylococcus aureus(11.3%) and Vibrio parahaemolyticus (3.2%). In this study, we conducted the isolation and enumeration for S. aureus in Kimbap. This monitoring data will be applied to the following study, risk assessment. The Kimbap samples were collected from department stores, convenient stores and snack bars located in Seoul, Busan, Daejeon, and Gwangju. The overall isolation rate of S. aureus from 214 Kimbap samples was 34.1% and the average count was 623 cells. Enterotoxin typing test for isolates showed 42.5%, 4.1% and 2.7% for type, A, B and C, respectively. There was no significant seasonal difference in S. aureus isolation, but the average count in summer(793 cfu/g) was 1.8 times higher than that of winter(446 cfu/g).

• Culinary science and hospitality research
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• v.17 no.3
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• pp.141-150
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• 2011

The objective of this study is to monitor the microbiological effect on preschool children's hand safety according to educational methods of hand washing. The subjects were ten children aged three to five. The analyses of the microbiological effect were made before band washing education, after one-week video demonstrations of hand washing education, and after one-week video demonstrations of hand washing education combined with practice. The results were as follows. Total plate count, filamentous fungi, coliform, and Staphylocuccus aureus were detected from children's hands just before band washing education. According to the two-week hand washing education, such education was found effective in keeping the children's hands clean and safe. In conclusion, repeated and more consistent training of band washing would be important for children, especially aged three to five because most of the habits and behavior patterns were developed in these age groups and the effects were persistent during their future life.