• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.52 no.6
• /
• pp.625-630
• /
• 2019

The pathogenic Vibrio genus contains halophilic bacteria that are distributed in marine and freshwater environments. Vibrio cholerae, Vibrio vulnificus, and Vibrio parahaemolyticus are potent human pathogens and leading causes of septicemia, wound infection, and seafood-borne gastroenteritis. The aim of this study was to investigate the presence of pathogenic Vibrio species in seawater off the west coast of Korea. Sixty-four seawater samples were obtained from different sites in Gomso Bay and Byeonsan from April 2018 to November 2018. Pathogenic Vibrio species were detected using a combination of most probable number (MPN)-polymerase chain reaction methods. V. cholerae, V. vulnificus, and V. parahaemolyticus were found in 0.0%, 20.3%, and 65.6% of seawater samples, respectively. Quantitative results revealed 3.6-23 MPN/100 mL of V. vulnificus, and 3.6-930 MPN/100 mL of V. parahaemolyticus in the samples. Overall, these results provide new insight into the necessity for seawater sanitation in Gomso Bay and Byunsan; they also provide evidence that will help reduce outbreaks of seafood-borne illness caused by pathogenic Vibrio species.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.55 no.6
• /
• pp.844-849
• /
• 2022

The pathogenic Vibrio genus denotes halophilic bacteria that are distributed in aquatic environments, including both sea and freshwater. V. cholerae, V. vulnificus, and V. parahaemolyticus are the main species that can be potent human pathogens and the leading cause of septicemia, wound infections, and seafood borne gastroenteritis. The aim of this study was to investigate the presence of pathogenic Vibrios in seawater. We obtained a total of 80 seawater samples from the Geum River estuary area in the west coast of Korea from April to December 2021. Pathogenic Vibrios was determined using a combination of the most probable number-polymerase chain reaction (MPN-PCR) methods. The detection levels of V. cholerae, V. parahaemolyticus, and V. vulnificus in the seawater samples were 7.5%, 68.8%, and 30.0%, respectively. The quantitative results were as follows: 3.6-3.6 MPN/100 mL in V. cholerae, 3.6-3,400 MPN/100 mL in V. parahaemolyticus, and 3.6-4,300 MPN/100 mL in V. vulnificus. Overall, these results provide novel insight into the necessity for seawater sanitation in the Geum River estuary area, and could help reduce the risk of seafood-borne outbreaks caused by pathogenic Vibrios.

• Natural Product Sciences
• /
• v.19 no.4
• /
• pp.297-302
• /
• 2013

The current study was conducted to evaluate the antibacterial and antioxidant activities of the essential oil fraction from the roots of Angelica tenuissima Nakai and its main components. We extracted the essential oil fraction from the roots of A. tenuissima using steam distillation and isolated its main components. Their antibacterial activities were determined by broth dilution test against food-borne pathogenic bacteria. Antioxidant activities were evaluated by DPPH-scavenging assay and reducing-power test. Also tested was their ability to inhibit the growth of two gastrointestinal cancer cell lines, Caco-2 and MKN-45. The A. tenuissima oil fraction and its main components, ligustilide and butylidene phthalide exhibited marked inhibitory effects against most of the tested antibiotic-susceptible and antibiotic-resistant bacterial strains with minimum inhibiting concentrations (MICs) from $0.21{\pm}0.08$ to $3.60{\pm}0.89mg/ml$. They also showed growth-inhibiting activity against Caco-2 and MKN-45 cells. The oil fraction showed significant antioxidant activities in DPPH radical scavenging assay and reducing-power test. Taken together, A. tenuissima essential oil could be used as a safe additive for preventing food contamination by pathogenic bacteria. Additionally, its antioxidative activity and the ability to inhibit gastrointestinal carcinoma cell lines could increase its value for functional foods and prevention of cancer.

• Journal of Food Hygiene and Safety
• /
• v.19 no.2
• /
• pp.60-65
• /
• 2004

120 samples of ready-to-eat salad product were purchased at department stores, marts and family restaurants in metro area. Coliform bacteria and food borne pathogenic bacteria were isolated from these samples. In 73 samples among the 120 salad product samples, coliform bacteria and food borne pathogenic bacteria were detected by 60.8％ of isolated rate. Salad were classified into organic and non-organic salad. According to a salad type, salad were classified into vegetable salad and mixed vegetable salad with fried chicken and extra food. According to a packing type, packed salad product and salad-bar product were classified. After the classification, the results of each cases were compared. There is no statistical relation between cultivation or packing methods and contaminated bacteria. But the incidence number of microbial strains was significantly different between vegetable salad and mixed vegetable salad(p＜0.005). In vegetable salad, more various strains were detected. E. coli was isolated in 10 cases among the 90 cases in non-organic vegetable and in 7 cases among the 30 cases in organic salad. Food borne pathogenic bacteria were isolated in non-organic vegetable salad product. Staphylococcus aureus was isolated in 4 cases of vegetable salad product and Salmonella spp. isolated in 1 case. After 5 times examination of each 4 market products, the total number of aerobic bacteria was average 4.8$\pm$0.19 log cfu/g. One sample from this product, saline and a detergent for vegetable were used for 3 minutes to notice the effect. As a result, when saline was used 5 times and detergent for vegetable was used 1 time, bacterial contamination was decreased up to 95.5％.

• Korean Journal of Food Science and Technology
• /
• v.37 no.6
• /
• pp.1005-1011
• /
• 2005

Widespread distributions of repetitive DNA elements in bacteria genomes are useful for analysis of genomes and should be exploited to differentiate food-borne pathogenic bacteria among and within species. Enterobacterial repetitive intergenic consensus (ERIC) sequence has been used for ERIC-PCR genomic fingerprinting to identify and differentiate bacterial strains from various environmental sources. ERIC-PCH genomic fingerprinting was applied to detect and differentiate four major Gram-negative food-borne bacterial pathogens, Esherichia coli, Salmonella, Shigella, and Vibrio. Target DNA fragments of pathogens were amplified by ERIC-PCR reactions. Dendrograms of subsequent PCR fingerprinting patterns for each strain were constructed, through which relative similarity coefficients or genetic distances between different strains were obtained numerically. Numerical comparisons revealed ERIC-PCR genotyping is effective for differentiation of strains among and within species of food-borne bacterial pathogens, showing ERIC-PCR fingerprinting methods can be utilized to differentiate isolates from outbreak and to determine their clonal relationships among outbreaks.

• Journal of Food Hygiene and Safety
• /
• v.32 no.3
• /
• pp.222-227
• /
• 2017

This study aimed to explore the potential for food-industry application of atmospheric pressure dielectric barrier discharge plasma (atmospheric pressure DBD plasma) as a non-thermal sterilization technology for microorganism. The effects of the key parameters such as power, oxygen ratio, exposure time and distance on Escherichia coli KCCM 21052 sterilization by the atmospheric pressure DBD plasma treatment were investigated. The experimental results revealed that increasing the power, exposure time or oxygen ratio and decreasing the exposure distance led to an improvement in the sterilization efficiency of E. coli. Furthermore, the atmospheric pressure DBD plasma (1.0 kW power, 1.0% (v/v) $O_2$, 5 min exposure time and 20 mm exposure distance) treatment was very effective for the sterilization of food-borne pathogenic bacteria. The sterilization rate of E. coli, Bacillus cereus KCCM 40935, Bacillus subtilis KCCM 12027, Bacillus thuringiensis KCCM 11429 and Bacillus atrophaeus KCCM 11314 were 72.3%, 74.6%, 88.5%, 84.7% and 91.3%, respectively.

• Food Science and Biotechnology
• /
• v.18 no.2
• /
• pp.425-431
• /
• 2009

Antimicrobial coating on chicken carcasses may reduce the effects of cross-contamination and improve product shelf-life and safety. Thyme oil was mixed at 0.5%(v/v) with a pre-gelatinized pea starch coating solution. The coating solution was spread on chicken breast meat after inoculation with selected spoilage and pathogenic bacteria. After inoculation, the chicken meats were packaged in plastic bags and stored at $4^{\circ}C$. During 12 day storage, total aerobic bacteria, lactic acid bacteria, and inoculated organisms were counted at 4 day intervals. Thyme oil treatments reduced the viability of Salmonella as well as the growth of Listeria and Pseudomonas by 2 log CFU/g, and appeared to eliminate inoculated Campylobacter during storage. The addition of thyme oil increased the viscosity of the pre-gelatinized pea starch solution. The results suggested that thyme oil inclusion in an edible starch coating may be a satisfactory delivery system to enhance the safety of processed fresh meat.

• Food Science and Biotechnology
• /
• v.17 no.6
• /
• pp.1345-1348
• /
• 2008

Titanium dioxide ($TiO_2$) shows antibacterial effects when exposed to near ultra violet (UV) light. In this study, $TiO_2$ photocatalytic continuous reactor was designed and applied to food-borne pathogens such as Vibrio parahaemolyticus ATCC 17802, Salmonella choleraesuis ATCC 14028, and Listeria monocytogenes ATCC 15313. $TiO_2$ films were prepared by conventional sol-gel dip-coating method using titanium tetra iso-propoxide (TTIP). The antibacterial activity of photocatalytic reactor with various flow rates and UV-A illumination time showed effective bactericidal activity. As the UV-A illumination time increased, survival rates of those bacteria decreased. After 60 min of UV-A illumination, the survival rates of V. parahaemolyticus and S. choleraesuis were less than 0.1%. However, that of L. monocytogenes was about 5% at that time point. These results present an effective way to exclude pathogenic bacteria from aqueous foods.

• Microbiology and Biotechnology Letters
• /
• v.49 no.1
• /
• pp.18-23
• /
• 2021

The aim of this study was to determine the production of folate, short chain fatty acids (SCFAs), and antimicrobial activity exhibited by Lactobacillus plantarum G72 for potential dietary application in pregnant women. L. plantarum G72 has been reported to possess characteristic activities and functionality including β-galactosidase activity and antioxidant activities. L. plantarum G72 showed antibacterial activity against pathogenic bacteria (Listeria monocytogenes ATCC 15313, Salmonella typhimurium P99, Escherichia coli ATCC 25922, and Staphylococcus aureus KCCM 11335) using a modified method, and formation of the largest inhibition zone was observed against S. aureus KCCM 11335 (12.0-17.0 mm). The adherence of four food-borne pathogenic bacteria to HT-29 cells was inhibited by L. plantarum G72 (0.13 to 0.92 log CFU/ml). The most considerable inhibition of adherence to HT-29 cells was observed by using L. plantarum G72 against S. typhimurim P99. Additionally, folate production by L. plantarum G72 was 50.1 ng/ml, and L. plantarum G72 produced relatively more lactic acid (11,176.73 mg/kg) than acetic, propionic, or butyric acids. Therefore, the results of this study suggest that L. plantarum G72 may serve as a multifunctional food additive in the health industry.

• Korean Journal of Environmental Agriculture
• /
• v.40 no.4
• /
• pp.248-259
• /
• 2021

BACKGROUND: Contaminated water was a major source of food-borne pathogens in various recent fresh produce-related outbreaks. This study was conducted to investigate the microbial contamination level and correlations between the level of sanitary indicator bacteria and the detection ratio of pathogens in agricultural water by logistic regression analysis. METHODS AND RESULTS: Agricultural water was collected from 457 sites including surface water (n=300 sites) and groundwater (n=157 sites) in South Korea from 2018 to 2020. Sanitary indicator bacteria (total coliform, fecal coliform, and Escherichia coli) and food-borne pathogens (pathogenic E. coli, E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were analyzed. In surface water, the coliform, fecal coliform, and E. coli were 3.27±0.89 log CFU/100 mL, 1.90±1.19 log CFU/100 mL, and 1.39±1.26 log CFU/100 mL, respectively. For groundwater, three kinds of sanitary indicators ranged in the level from 0.09 - 0.57 log CFU/100 mL. Pathogenic E. coli, Salmonella and Listeria monocytogenes were detected from 3%-site, 1.5%- site, and 0.6%-site water samples, respectively. According to the results of correlations between the level of sanitary indicator bacteria and the detection ratio of pathogens by logistic regression analysis, the probability of pathogen detection increased individually by 1.45 and 1.34 times as each total coliform and E. coli concentration increased by 1 log CFU/100mL. The accuracy of the model was 70.4%, and sensitivity and specificity were 81.5% and 51.7%, respectively. CONCLUSION(S): The results indicate the need to manage the microbial risk of agricultural water to enhance the safety of fresh produce. In addition, logistic regression analysis is useful to analyze the correlation between the level of sanitary indicator bacteria and the detection ratio of pathogens in agricultural water.