• Journal of environmental and Sanitary engineering
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• v.20 no.1 s.55
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• pp.12-22
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• 2005

This study was performed to survey distribution of microorganisms and food-borne pathogenic bacterium in order to estimate microbiological safety in seonsik and saengsik. Total aerobic bacteria was detected over $10^5\;CFU/g$ in raw materials($4.3\%$) and products($35.7\%$) of saengsik. Coliforms were detected over $10^2\;CFU/g$ in seonsik products($27.3\%$) and in raw materials($4.3\%$) and products($35.7\%$) of saengsik. Cl. perfringens was detected in saengsik products($4.8\%$). B. cereus was detected in raw materials($12.5\%$) and products($18.2\%$) of seonsik and raw materials($13.0\%$) and products($23.8\%$) of saengsik. Concentration and detection rate of microorganisms in products were higher than raw materials. These results show some food hygiene problems but do not cause food poisoning because concentration of Clostridium perfringens and B. cereus were lower than $10^5\;CFU/g$.

• Journal of Food Hygiene and Safety
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• v.21 no.2
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• pp.60-64
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• 2006

In this study, we evaluated bacteriocidal effect of CaO (scallop shell powder) for the reduction of microorganism in lettuce, and compared with main chemical sanitizers such as chlorine, ethanol, hydrogen peroxide. As a result, the effectiveness of CaO showed dramatic reduction rate for total aerobic bacteria, Escherichia coli, Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, and Salmonella Typhimurium and were $5.9{\times}10^3,\;1.3{\times}10^5,\;5.9{\times}10^3,\;2.7{\times}10^6,\;3.6{\times}10^3,\;4.5{\times}10^3\;and\;2.6{\times}10^4$, respectively. CaO did not show better disinfecting efficiency than chlorine or hydrogen peroxide which were used as sanitizer. In Bacillus cereus case, it showed $10^6$ reduction rate, and were $10^2{\sim}10^5$ times better reduction than ethanol sanitizer. According to these results, CaO can alternate the currently used chemical sanitizers due to its natural origin as well as the effectiveness for sterilization.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.144-151
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• 2012

In the course of this study aimed at the development of functional food ingredients from seaweeds, the in vitro antimicrobial activities of methanol extracts prepared from 35 different seaweeds (17 phaeophyta, 11 rhodophyta and 7 chlorophyta) were determined against food-borne diseases and pathogenic microorganisms including multi-drug resistant (MDR) Pseudomonas sp. and Candida sp. Based on disc-diffusion assays at 500 g/disc concentration of the methanol extracts, Ishige okamurai, I. foliacea, Sargassum confusum, and S. yamade exhibited strong antibacterial activities in a broad-spectrum, except against Pseudomonas aeruginosa. In addition to the latter four seaweeds, Ecklonia stolonifera, E. cava and Eisenia bicyclis also demonstrated antifungal activity against C. albicans. Among these 8 selected seaweeds, I. okamurai, I. foliacea, and S. yamade exhibited strong hemolytic activity (55-93%) at 500 g/ml against human RBC. Organic solvent sequential fractions using hexane, ethylacetate and butanol, and water residues were prepared from the 8 selected seaweeds and their anti-Candida sp. activities were further determined. The ethylacetate and butanol fraction of I. okamurai, and the hexane fraction of I. foliacea demonstrated antifungal activity against MDR-pathogenic Candida sp. Although the solvent fractions had no activity against MDR-Pseudomonas sp., our results suggest that seaweeds, especially Ishige okamurai, I. foliacea, S. confusum, and S. yamade could be developed as broad-spectrum antimicrobial ingredients.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.2
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• pp.160-169
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• 2000

This study was conducted to understand the inhibitory garlic and ginger against the growth of food born pathogenic bacteria. Juice was prepared from the raw spices by using an electric homogenizer and membrane filter. Dry-powdered spices were treated with double distilled water and 70% ethanol to extract the antibacterial substances, respectively. Growth inhibitory effects of juice and extracts of the spices were monitored by using bacterial strains such as B. subtilis, L. moncytogenes, S. aureus,E. coli O157 : H7, P. aeruginosa, and S. typhimurium. On a solid medium where E. coli and S. aureus cells were grown, ginger juice formed inhibitory zone at the concentrations of 2-10% by paper disc test. The Bone formed by ginger juice was wider and more transparent than that formed by garlic juice on the same concentration.1. monocytogenes and B. subtilis were more sensitive to garlic juice than others, and stopped growing at 2% garlic juice. Ginger juice showed the growth inhibition by 30-50% at 1.0% concentration. On the contrast, P. aeruginosa which resisted to the garlic juice was the most sensitive to ginger juice. Water extract of garlic was not effective to inhibit the bacterial growth, while 2% ginger extract completely inhibited the growth of E. coli and S. aureus. Alcohol extract of ginger inhibited the growth of bacteria at the concentration of 0.3%. This growth inhibition is almost 10 times lower than that of the garlic extract. It was clear that ginger had more potential than garlic as an inhibitor to control the growth of the indicator organisms.

• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.531-536
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• 1995

Salmonella species are the most prevalent etiologic agents of food-borne acute gastroenteritis. Direct isolation of bacteria from the contaminated food, stool and animal tissues has been used for the diagnosis of salmonellosis routinely. However, isolation of bacteria is time consuming work and not so highly sensitive. In recent years, improved methods of polymerization chain reaction(PCR) and probe hybridization technique have led to the developement of diagnostic assays which employ to detect various human and animal pathogenic bacteria. In this study, we have performed the polymerization chain reaction to detect Salmonella pullorum from tissues and stool samples of chickens with two specific primers, ST5 and ST8C. The target DNA fragment of PhoE gene was successfully amplified from liver, spleen, pancreas, heart, lung, ovary, oviduct and feces samples. The amplified DNA fragments were hybridized with Salmonella typhymurium TA3000 PhoE probe by Southern hybridization. The PCR to amplify the PhoE gene was highly rapid and sensitive method to detect Salmonella pullorum from tissues and stool samples.

• Korean Journal of Food Science and Technology
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• v.49 no.2
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• pp.146-150
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• 2017

Staphylococcus aureus is a pathogenic bacterium that causes food poisoning, exhibits a strong capacity to form biofilm, and is highly resistant to antimicrobial agents. The purpose of this study was to investigate the antimicrobial characteristics of corosolic acid against S. aureus. S. aureus showed high susceptibility to corosolic acid in a concentration-dependent manner. The minimum inhibitory concentration and colony-forming ability determined by the broth microdilution method showed that corosolic acid had strong antimicrobial activity against the bacteria. The diameters of the inhibition zone and numbers of colony forming units at each concentration of corosolic acid were also measured. In addition, corosolic acid displayed potent biofilm inhibition activity against S. aureus at concentrations below its minimum inhibitory concentration. These results suggest that corosolic acid can be used to effectively prevent biofilm formation by S. aureus, thereby making S. aureus more susceptible to the action of antimicrobials.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.514-517
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• 2004

O157:H7, Salmonella typhimurium, Listeria monocytogenes were treated with aqueous chlorine dioxide to elucidate effect of aqueous chlorine dioxide treatment on major food-borne pathogenic bacteria. Survival plot of E.coli O157:H7 at 5 ppm chlorine dioxide showed typical first-order rate. After 5 min of treatment, cell number decreased by 1.5 log cycle. Survival plot slope gave D value of 3.37 min. S. typhimurium and L. monocytogenes showed biphasic curve. Aqueous chlorine dioxide treatment on S. typhimurium and L. monocytogenes resulted in bactericidal effect for 5 min, and thereafter no effect was observed under experimental conditions of this study. These results suggest concentration of chlorine dioxide is more important than treatment time, and 5 ppm chlorine dioxide treatment is not sufficient for sanitizing fresh vegetables.

• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.232-237
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• 2022

The present study investigated the bactericidal effects of chlorine dioxide (CD) and electrolyzed water (EW) on pathogenic bacteria, such as Bacillus cereus, Staphylococcus aureus, Salmonella Typhimurium, and Escherichia coli O157:H7, by treatment them with CD and EW, respectively, for 0, 2, 4, 6, 8, and 10 min. Additionally, the sensitivities of Gram-positive (B. cereus and S. aureus) and Gram-negative (S. Typhimurium and E. coli O157:H7) to CD and EW were compared, respectively. In CD, the D-values for B. cereus, S. aureus, S. Typhimurium, and E. coli O157:H7 were 1.85±0.64, 2.06±0.85, 2.26±0.89, and 2.59±0.40 min, respectively. In EW, the D-values for B. cereus, S. aureus, S. Typhimurium, and E. coli O157:H7 were 2.13±0.32, 1.64±0.64, 1.71±0.32, and 1.86±0.36 min, respectively. All strains decreased consistently for 10 min in both CD and EW. However, the D-values of each bacterial species did not differ significantly between CD and EW (P>0.05). When comparing the bactericidal effect of CD and EW, no difference in D-value was observed, even though the pH and available chlorine concentration of CD were significantly lower than those of EW. These data could be used for the application of CD and EW in the food industry, considering characteristics such as the selection of optimal disinfectants, determination of optimal concentrations, and sensitivity to disinfection targets.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.103-108
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• 2015

Weissella spp. from traditional Korean foods of Kimchi were isolated and characterized against food-borne pathogenic Listeria monocytogens. The isolates were identified as W. cibaria 0D17 and W. confusa 0D23 from Kimchi by the biochemical characteristics and 16S DNA sequencing. The culture solutions of the isolates adjusted to pH 7.0 showed L. monocytogens inhibition. To analyze the quantitative detection of L. monocytogenes, real-time PCR was performed according to the SYBR Green I method. The isolates grew well and L. monocytogens did not grow during the co-culture with those strains at $37^{\circ}C$. Therefore, W. cibaria 0D17 and W. confusa 0D23 might be the candidates as the functional lactic acid bacteria for improving food safety.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.804-810
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• 2010

This study was performed to select protease-producing Bacillus sp. as a potential probiotic starter for fermented meat products. In order to isolate protease-producing bacterium from meju, measured the diameter of the clear zone on agar plate (TSA, 1% (w/v) skim milk) and analyzed for intracellular protease activity, then 10 Bacillus-like strains were isolated. Three Bacillus-like strains (P19, P27, and P33) among 10 strains were able to tolerate in acidic condition (TSB, pH 2.5, 2 h incubation). These 3 strains were showed antimicrobial activity against food-borne pathogenic bacteria. These vegetative cells of 3 strains were showed a survival rate of 0.04% to 0.08% under the artificial gastric acidic condition (TSB, pH 2.5 with 1% (w/v) pepsin), but spore-forming cells were 56.29% to 84.77%. Vegetative cells of 3 strains were the least bile-resistant, while spore-forming cells of 3 strains showed higher survival rate more than 76% under artificial bile condition (TSB, 0.1% (w/v) oxgall bile). In these strains, P27 strain was finally selected as a good probiotic strain. P27 strain was tentatively identified as Bacillus amyloliquefaciens by API CHB kit and 16S rDNA sequence analysis. The results of this study suggest that B. amyloliquefaciens P27 can be used as a potential probiotic starter for fermented meat product.