• Food Science and Preservation
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• v.20 no.3
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• pp.419-423
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• 2013

The objective of this study was to characterize the bactericidal effect of 461nm visible-light LED on three common foodborne bacteria: Escherichia coli O157:H7, Staphylococcus aureus and Vibrio parahaemolyticus. Tests were conducted against pathogen strains that were treated with 461nm LED for 10 h at $15^{\circ}C$. The E. coli (ATCC 43894, ATCC 8739 and ATCC 35150) and the S. aureus (ATCC 27664, ATCC 19095 and ATCC 43300) had average reductions of 2.5, 6.6, 1.5, 2.5 and 2.0 log CFU/mL, respectively, after they were exposed for 10 h to 461nm LED light (p<0.05). In contrast, V. parahaemolyticus (ATCC 43969) had 6 log CFU/mL reductions after it was exposed for 4 h to 461nm LED light. The results showed that both the Gram-positive and Gram-negative bacteria were inactivated with 461nm LED light exposure. Also, the Gram-negative bacteria were more sensitive to the LED treatment than the Gram-positive bacteria. These results show the potential use of 461nm LED as a food preservation and application technology.

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.37-44
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• 2006

Ecotoxicity assessments of 90 selected effluents of 22 industry types from 2002 to 2004 in Korea were evaluated by a toxic battery of bioassay test using fish Oryzias latipes, invertebrate Daphnia magna, algae Selenastrum capricornutum and bacteria Vibrio fischeri with the physicochemical measurement items and permit concentrations on the present Water Quality Conservation Act in Korea. Total toxic unit (${\Sigma}TU$) of 8 industry types of 22 industry types by the toxic battery appeared in order of the value site as follows; Pigment Dye Manufacturing (${\Sigma}TU$ 217.1) > Textile and Dye (${\Sigma}TU$ 39.3) > Semiconductor Electronic Manufacturing (Small) (${\Sigma}TU$ 25.6) > Wastewater and Sewage Treatment Plants (${\Sigma}TU$ 25.4) > Coating (${\Sigma}TU$ 23.8) > Leather Skin Manufacturing (${\Sigma}TU$ 18.0) > Synthetic Resin Manufacturing (${\Sigma}TU$ 15.6) > Assemble Metal Manufacturing (${\Sigma}TU$ 10.7). Our results demonstrate that ecotoxicity assessment, by bioassay test, is effective and practical for industrial wastewater management for 90 selected effluents with the limitation of the physicochemical permit. Among 90 effluents, 9 samples failed physicochemical permit limitation and 81 passed it. In result of ecotoxicity assessment of 90 effluents by the toxic battery, 76 effluents exhibited ecotoxicity and the others did not. The physicochemical measurement items and permit concentrations on the present Water Quality Conservation Act in Korea were low related to the ecotoxicity value by the toxic battery and appeared limited for water quality management to water-ecosystem and environment-friendly management of water.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.241-246
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• 2012

This report outlines the development of a rapid, simple, and sensitive detection system for pathogenic bacteria using a capillary electrophoresis-based, single strand conformation polymorphism (CE-SSCP) combined with PCR. We demonstrate that this method, used with primers targeting the V4 region of the16S rRNA gene, is capable of the simultaneous detection of 10 microbes that could be associated with foodborne illness, caused by animal-derived foods: Salmonella enterica, Listeria monocytogenes, Escherichia coli O157:H7, Campylobacter jejuni, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Yersinia enterocolitica, Vibrio parahaemolyticus, and Enterobacter sakazakii. The traditional detection techniques are time-consuming and labor-intensive, due to the necessary task of separate cultivation of each target species. As such, the CE-SSCP-PCR method, that we have developed, has the potential to diagnose pathogens rapidly, unlike the traditional technique, in order to prevent foodborne illness in a much more efficient manner.

• Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.241-250
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• 2012

Polycyclic aromatic hydrocarbons (PAHs), butyltins (BTs), nonylphenol (NP), and fecal sterols concentrations in sediments were investigated from Gunsan coast of Korea to evaluate organic pollution from anthropogenic activities. Sediment toxicity was also examined by bacterial bioluminescence toxicity test (Vibrio fischeri). The concentrations of 16 PAHs in sediments ranged from 67.9 to 425 ng/g dry wt; BTs ranged from 2.79 to 14.1 ng Sn/g dry wt; NP ranged from 20.7 to 2171 ng/g dry wt; and coprostanol, a fecal sterol, ranged from 7.60 to 245 ng/g dry wt. Effective concentration 50% ($EC_{50}$) of sediments ranged from 0.38 to 23.8 mg/mL. Most of the chemicals were present at levels lower than or comparable to the previously reported values from Korea. However, NP levels in the present study were in the high range of levels reported from the Korean coast, and 40% of the measured samples exceeded screening and ecotoxicological values of NP suggested by the Netherlands and Canada. This suggests that an ongoing source of NP is a serious concern in the Gunsan coast. High levels of contaminants were found in the proximity of potential sources, such as the outfall of a wastewater treatment plant for NP, an anthracite-fired power plant for PAHs, and ports for BTs, fecal sterols, and sediment toxicity. This indicates that Gunsan coast has various potential sources of marine sediment contaminants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.389-396
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• 2018

Marine pathogenic bacteria, such as Streptococcus parauberis, Edwardsiella tarda and Vibrio harveyi, can cause lethal infections in farmed fish, ozone and antibiotics, are employed to sterilize waters used for rearing fish to mitigate this threat. The most widely used method is treatment with sodium hypochlorite solution. However, the maintenance of a constant concentration of chlorine in rearing waters can be difficult. We investigated the potential of a mixed oxidant (MO) solution generated by electrolysis of sea water to improve water quality. We measured the survival rates of fish pathogenic bacteria exposed to different concentrations of MO (0.5, 1.0, 1.5 and 2.0 MO) and sodium hypochlorite (0.5, 1.0, 1.5 and 2.0 ppm) for various lengths of time (0, 5, 10, 15, 20, 25 and 30 min). We found a time-dependent decrease in the survival rates of the tested pathogenic microorganisms. The sterilization effect of the MO solution on pathogenic organisms was greater than that of sodium hypochlorite for gram-negative and gram-positive bacteria. We conclude that MO solution produced by electrolysis could be used to maintain a constant chlorine concentration in aquaculture systems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1233-1238
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• 2003

The growth inhibitory effects of chloride salts and organic acid salts against six food-borne microorganisms (Bacillus cereus ATCC 11778, Escherichia coli O157:H7 ATCC 43894, Listeria monocytogenes ATCC 19111, Salmonella Typhimurium ATCC 14028, Staphylococcus aureus ATCC 25923, Vibrio parahaemolyticus ATCC 17802) were determined using Bioscreen C in broth medium. The growth inhibitory concentrations of sodium chloride and potassium chloride on B. cereus were 7 and 9%, respectively. E. coli O157:H7 and S. aureus were inhibited by treatment of 3% calcium chloride. Magnesium chloride showed growth inhibitory effect on B. cereus, S. Typhimurium, and S. aureus at 5%. The order of growth inhibition effects by organic acid salts was calcium propionate>calcium acetate>calcium lactate. Calcium chloride (3%) with 0.01% lactic acid showed strong inhibition on the growth of S. Typhimurium and exhibited stronger growth inhibition than calcium chloride alone (5%). We concluded that calcium chloride and calcium propionate had strong growth inhibitory activities and that calcium chloride and sodium chloride in combination with lactic acid had stronger inhibitory activities than that of chloride salts alone.

• Food Science of Animal Resources
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• v.18 no.1
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• pp.27-34
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• 1998

This study was carried out to evaluate of the microbial and sensory quality of ready-made hamburger and sandwich. Initial total plate count of hamburger for establishment A and B were 1.2$\times$102 cfu / g and 3.4$\times$102 cfu / g, respectively, and for establishment C was 7.9$\times$104 cfu / g. After 48 hour storage at 1$0^{\circ}C$, total plate count of hamburger for establishment A and B increased to 1.2$\times$104 cfu / g and 6.8$\times$103, respectively, and for establishment C increased to 1.2$\times$107 cfu / g. Initial total plate count of sandwich for establishment A and B were 3.2$\times$102 cfu / g 7.9$\times$102 cfu / g, respectively, and for establishment C was 1.1$\times$105 cfu / g. After 48 hour storage at 1$0^{\circ}C$, total plate count of hamburger for establishment A and B increased to 8.1$\times$103 cfu / g and 2.3$\times$104, respectively, and for establishment C increased to 4.4$\times$108 cfu / g. No E. coli, Salmonella, Vibrio, and Staphylococcus aureus were detected under simulated storage conditions. There was no significant changes in pH, acid value, and volatile nitrogen number under simulated conditions. In sensory evaluation of hamburger and sandwich, sensory score was lowered by increase of total plate count.

• Journal of Aquaculture
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• v.12 no.1
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• pp.7-14
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• 1999

Protoplasts were isolated from the vegetative thalli of Meristotheca papulosa using several commercial and crude enzymes. The suitable enzyme combination for the protoplast isolation was 4% abalone acetone powder, 4% Macerozyme R-10 and 4% Hemicellulase in the filtered seawater buffered with 50mM MES (pH 6.0) containing 0.6M mannitol and 0.5% potassium dextran sulfate. Yield of protoplast was $107.6{\times}10^4$ cells per gram of fresh thallus. Protoplasts were whitish ovoid in shape and ranged between $7{\mu} m$~ $24{\mu} m$ in diameter. Division of protoplasts was first observed 9 days after culture in $ASP_{12}$ medium, and the germination occurred within 25 days. The addition of Guillard's antibiotics in culture media was harmful to the regeneration of protoplasts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.885-891
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• 1996

Various problems in fermented fish products have been a major obstacle to manufacture the product in large scale, which is mainly concerned with the food safety. In this review, salt-fermented anchovy was selected to elucidate the characteristics of microorganisms involved in fermentation; thereby, it is suggested for research areas to achieve the quality improvement of tile product. Different microorganisms were involved in fermentation of anchovy. Dominant species were reported to be Bacillus sp., Pseudomonas sp., and Micrococcus sp., other microorganisms were Vibro sp., Clostridim sp., Serratia sp., Achromobacter sp., Streptococcus sp., Breuibacterium sp., Halobacterium sp., Flavobacterium sp., Corynebacterium sp., Acinetobacter sp., Sarcina sp., Staphylococcus sp., Torulopsis sp., and Saccharomyces sp. To standardize the quality of fermented fish products, screening and isolation of promising microorganisms should be carried out to develop different types of products; at the same time, proper sanitation control should be employed to keep the commercial value of the product by prolonging the shelf life.

• Journal of Environmental Health Sciences
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• v.33 no.3
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• pp.184-189
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• 2007

Pathogenic microbial foodborne disease outbreaks (PMFBDOs) have increased in many countries, the boom in food service establishment is not matched by effective food safety and control. In this study, we investigated the current state and the epidemic aspects of FBDOs in Korea and Japan. In Korea, the average prevalence rate of foodborne disease (FBD) was 15.0 per 100,000 population and cases per outbreak of FBD was 57.0. During the same period in Japan, the prevalence rate showed an average of 24.9, and the cases per outbreak were 16. When both prevalence rate and cases per outbreak were compared, the prevalence rate in Japan was much higher than that in Korea (p<0.01). However, average cases per outbreak of FBD in Japan were much lower than those in Korea (p<0.01). In Korea, outbreaks of FBDs were more common in spring (p<0.01), while in Japan, more frequent in summer and winter (p<0.01). Outbreaks of FBD occurred largely through restaurant and school foods (32.0% and 27.5%) in Korea. In Japan, the proportion of the outbreak cases in the restaurant and home were 23.7% and 12.1%, and cases of unknown causes of FBDs were 48.2%, respectively. Bacteria were the major causes of infection in both countries. The prevalence of PMFBDOs by Salmonella spp. Vibrio parahemolyticus and Staphylococcus aureus were much higher in Korea, while those by Camphylobacter spp. and SRSV were more common in Japan. The causes by virus were more frequent in Japan (13.7%) than in Korea (7.7%). The prevalence of FBDs in Korea and Japan showed characteristic differences, especially in the PMFBDOs due to such factors as geography, climate, culture, diet and food management.