• Fisheries and Aquatic Sciences
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• v.21 no.7
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• pp.18.1-18.6
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• 2018

Background: Cutaneous bacterial pathogens including Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Propionibacterium acnes are often involved in acne vulgaris. The currently available therapeutic option for these skin pathogens is an antibiotic treatment, resulting in the emergence of antibiotic-resistant bacteria. The objective of this study was to discover an alternative antibacterial agent with lower side effect from marine algae. Results: The ethanolic extract of edible brown algae Ishige okamurae exhibits potent antibacterial activity against cutaneous bacterial pathogens. Among the ethanol soluble fractions, the n-hexane (Hexane)-soluble fraction exhibited the strongest antibacterial activity against the pathogens with MIC values ranging 64 to $512{\mu}g/mL$ and with minimum bactericidal concentration values ranging 256 to $2048{\mu}g/mL$. Furthermore, the combination with Hexane fraction and antibiotics (ceftazidime, ciprofloxacin, and meropenem) exhibited synergistic effect. Conclusion: This study revealed that the I. okamurae extract exhibited a synergistic antibacterial effect against acnerelated cutaneous bacterial pathogens acquired antibiotic resistant. Thus, the results of the present study suggested that the edible seaweed extract will be a promising antibacterial therapeutic agent against antibiotic-human skin pathogens and its infections.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.315-319
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• 2007

Biofilm formation on various surfaces is a well-known phenomenon and it has caused pollution problems, health and safety hazards, and substantial economic loss in many areas including the food industry. In the present study, Gamma irradiation at a dose of 2.0 kGy reduced the bacterial counts of Staphylococcus aureus and Pseudomonas aeruginosa suspensions by 6.7 and >6.5 log CFU/mL, respectively, and 30 ppm of sodium hypochlorite effectively reduced the counts of both bacterial suspensions to below the limit of detection ($<2\;log\;CFU/cm^2$). However, in bacterial biofilms attached to stainless steel, gamma irradiation at a dose of 10.0 kGy reduced the counts of S. aureus attached fur 1 hr and overnight by ${\geq}5.1\;and\;5.0\;log\;CFU/cm^2$, respectively. Gamma irradiation at a dose of 1.0 kGy reduced the counts of P. aeruginosa counts to below the limit of detection ($<2\;log\;CFU/cm^2$). On the contrary, S. aureus and P. aeruginosa cells attached to stainless steel chips were difficult to eliminate using sodium hypochlorite. Four hundred ppm of sodium hypochlorite reduced the counts of S. aureus and P. aeruginosa attached for 1 hr by 2.5 and $3.3\;log\;CFU/cm^2$, respectively.

• Microbiology and Biotechnology Letters
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• v.50 no.1
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• pp.95-101
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• 2022

Due to the pandemic caused by COVID-19, the demand for face masks is soaring and has often caused a shortage. The aim of this study was to evaluate the effect of ultraviolet (UV) and drying treatments on microbial contaminants in facial masks. To conduct this study, standard procedures were designed to develop samples contaminated by the control bacteria Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The contamination level of the standard samples was approximately 6.30 × 10⁶ CFU/ml, and the UV light treatment was performed 1, 3, 5, and 7 times. To evaluate the effect of the UV and drying treatments, the masks were first treated with UV 1, 2, and 3 times, followed by the drying process. As a result, the mask contaminated with E. coli and P. aeruginosa showed a bacterial rate of approximately 99.9% after 1 UV irradiation, and in the case of the S. aureus-contaminated mask, it exhibited a bactericidal rate of approximately 99.9% after 7 UV irradiations. However, when the drying process was included after UV irradiation, all the samples contaminated with E. coli, S. aureus, and P. aeruginosa showed a bactericidal rate of 99.9% or more. The results of this study suggest that UV and drying treatments can effectively reduce the bacterial contaminants in facial masks. In addition, these results provide fundamental data and appropriate sterilization methods for reusing masks.

• Food Science of Animal Resources
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• v.36 no.3
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• pp.405-411
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• 2016

The effects of gaseous ozone exposure on the bacterial counts and oxidative properties were evaluated in duck and chicken breast fillets, which were stored under a continuous flux of gaseous ozone (10×10⁻⁶ kg O₃/m³/h) at 4±1℃ for 4 d. The ozone generator was set to on for 15 min and off for 105 min, and this cyclic timer was set during storage. Ozone effectively reduced the growth of coliform, aerobic and anaerobic bacteria in both chicken and duck breast. However, lipid oxidation occurred faster in duck breast than chicken breast with higher degree of discoloration, TBARS value, and antioxidant enzyme (glutathione peroxidase and catalase) activity decline rates. It is concluded that ozone effectively controlled the growth of bacteria in both chicken and duck breast with less effects on oxidative deterioration in chicken breast.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.104-110
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• 2011

This study was conducted to improve the food functional and sensory food quality of Hizikia fusiforme by the fermentation of lactic acid bacteria. Seven strains of lactic acid bacteria isolated from traditional Korean fermented food were inoculated and cultivated in H. fusiforme water extract. Among them, Lactobacillus brevis LB-20, isolated from Kimchi, was selected for further study by considering the results of bacterial growth, DPPH radical scavenging activity, and sensory evaluation. No significant differences in proximate compositions (moisture, crude protein, crude fat, and crude ash) were observed by the fermentation of L. brevis LB-20. The most dramatical change was the conversion from glutamate to ${\gamma}$-aminobutyric acid (GABA) in H. fusiforme water extract fermented by L. brevis LB-20. The GABA content increased approximately 60-fold after 48 hr of fermentation. The bacterial fermentation also resulted in low-molecularization of the extract. The particle size of the fermented extract became approximately 4-fold smaller than that of the law extract. In addition, the analysis of volatile flavor compounds using GC/MS revealed that the bacterial fermentation dramatically removed off-flavors such as acetaldehyde, haxanal, diallyl disulphide and 1-penten-2-ol in the H. fusiforme extract.

• The Plant Pathology Journal
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• v.38 no.3
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• pp.194-202
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• 2022

Erwinia amylovora and Erwinia pyrifoliae cause fire blight and black-shoot blight, respectively, in apples and pears. E. pyrifoliae is less pathogenic and has a narrower host range than that of E. amylovora. Fire blight and black-shoot blight exhibit similar symptoms, making it difficult to distinguish one bacterial disease from the other. Molecular tools that differentiate fire blight from black-shoot blight could guide in the implementation of appropriate management strategies to control both diseases. In this study, a primer set was developed to detect and distinguish E. amylovora from E. pyrifoliae by conventional polymerase chain reaction (PCR). The primers produced amplicons of different sizes that were specific to each bacterial species. PCR products from E. amylovora and E. pyrifoliae cells at concentrations of 10⁴ cfu/ml and 10⁷ cfu/ml, respectively, were amplified, which demonstrated sufficient primer detection sensitivity. This primer set provides a simple molecular tool to distinguish between two types of bacterial diseases with similar symptoms.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.38-43
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• 2016

Novel and specific recognition elements are of central importance in the development of a pathogen detection method. Here, we describe a simple method for identifying the cell-wall binding domain (CBD) from a sequenced bacterial genome employing homology search for phage lysin genes. A putative CBD (CPF369_CBD) was identified from a genome of Clostridium perfringens type strain ATCC 13124, and its function was studied with the CBD-GFP fusion protein recombinantly expressed in Escherichia coli. Fluorescence microscopy showed the specific binding of the fusion protein to C. perfringens cells, which demonstrates the potential of this method for the identification of novel bioprobes for specific detection of pathogenic bacteria.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.668-674
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• 2020

Manuka honey (MH) has been shown anti-bacterial activity against several pathogenic bacteria. However, the inhibitory effect of MH on biofilm formation by Escherichia coli O157:H7 has not yet been examined. In this study, MH significantly reduced E. coli O157:H7 biofilm. Moreover, pre- and post-treatment with MH also significantly reduced E. coli O157:H7 biofilm. Cellular metabolic activities exhibited that the viability of E. coli O157:H7 biofilm cells was reduced in the presence of MH. Further, colony forming unit of MH-treated E. coli O157:H7 biofilm was significantly reduced by over 70%. Collectively, this study suggests the potential of anti-biofilm properties of MH which could be applied to control E. coli O157:H7.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.47-54
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• 1997

Fried vegetable mix, fried fish mix and fried chicken which prepared as convenient style at traditional market in Chonju were collected and evaluated their chemical composition, lipid and microbial changes during storage at different temperaturefor confirming those fried food stability. The POV and AV of oil in samples and total bacterial count during storage at 5, 15, 20 and 3$0^{\circ}C$ were monitered. The POV, AV and total bacterial count tested of each sample, shelf-life can be suggested as within 1 day at 3$0^{\circ}C$, 2~3 days at 15~2$0^{\circ}C$ and over 5 days at 5$^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.232-235
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• 2004

Since ready-to-use (RTU) products are not fully cooked, the shelf-life of the product is comparably short and the products are easily spoiled when contaminated with food-borne pathogens. Low-dose gamma irradiation of 0.5, 1, or 2 kGy effectively reduced the total aerobic bacterial counts in 2 Korean manufactured RTU products by 1.63 to 2.95 log CFU/g during cold storage. Irradiation at 2 kGy reduced the psychrotrophic bacterial counts in most of the samples to below the limit of detection (< log CFU/g). Irradiation at 0.5 kGy completely eliminated Escherichia coli from the commercial RTU samples.