• Proceedings of the Microbiological Society of Korea Conference
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• 2009.05a
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• pp.36-37
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• 2009

• Journal of the East Asian Society of Dietary Life
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• v.22 no.5
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• pp.692-700
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• 2012

The antibacterial activity of the ethanol extract of Cornus officinalis against some bacteria related to foodborne illness and food spoilage was investigated. In the case of the disc diffusion assay, clear zones due to the inhibition of proliferation by Cornus officinalis extract were 8.5~18.3 mm at $4,000{\mu}g/disc$. The inhibitory effect of Cornus officinalis was as follows: Escherichia. coli ${\geq}$ Listeria monocytogenes ${\geq}$ E. coli O157:H7 > Bacillus cereus > Staphylococcus aureus > Pseudomonas aeruginosa > Salmonella typhimurium. In addition, the MIC of Cornus officinalis extract toward B. cereus was the lowest at 1,000 ppm. The extract inhibited the growth of E. coli, L. monocytogenes, E. coli O157:H7, and Bacillus cereus throughout the growth stage. However, the growth of P. aeruginosa, S. aureus, and S. typhimurium was only inhibited by the extract during the lag phase. The constituents of all cells tested were released, especially E. coli and E. coli O157:H7. Observation of the cells using SEM demonstrated a morphological change and disruption of cells in response to treatment with Cornus officinalis extract. Based on these findings, the ethanol extracts of Cornus officinalis showed strong antimicrobial activity against all tested bacteria, indicating that Cornus officinalis can be a useful natural antimicrobial reagent.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.538-546
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• 2017

The occurrence of various pathogenic microorganisms on farms is a concern if they are able to contaminate fresh produce, which provides entry into the food supply. This study was undertaken to assess the microbiological quality and prevalence of pathogens in Chinese cabbage cultivated soil in Korea. A total of 57 Chinese cabbage cultivated soils were collected in 4 locations in Korea from February to August 2017. The soils were analyzed for the presence of total aerobic bacteria, Escherichia coli, coliforms, Salmonella spp., Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus. The total aerobic plate counts in soils were in the range of 5.7 to $8.7log\;CFU\;g^{-1}$. The coliforms and E. coli were detected in 39 and 8 out of 57 soil samples, respectively, in the range of 1.1 to $6.3log\;CFU\;g^{-1}$ and 0.7 to $4.0log\;CFU\;g^{-1}$. Salmonella spp., E. coli O157:H7, L. monocytogenes, and S. aureus were not detected from any samples. Results from these studies may help control the spread of bacterial species such as E. coli and Salmonella spp. through the farm environment.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.560-564
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• 2012

This study was undertaken to assess the microbiological quality and prevalence of pathogens in organic vegetables produced in Korea. A total of 189 organically grown vegetable samples (perilla leaf 50, lettuce 50, tomato 39, cucumber 50) were analyzed for the presence of aerobic plate count, Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, and Yersinia enterocolitica. The total aerobic plate counts were in the range of 4.2 to $7.7log\;CFU\;g^{-1}$ for perilla leaf, 5.0 to $8.0log\;CFU\;g^{-1}$ for lettuce, 4.0 to $7.5log\;CFU\;g^{-1}$ for tomato, and 6.6 to $8.6log\;CFU\;g^{-1}$ for cucumber. The highest counts were found in cucumber. E. coli O157:H7, Salmonella spp., S. aureus, L. monocytogenes, and Y. enterocolitica were not detected from any organically grown vegetable samples. This research suggests that continuous monitoring in organic vegetables is required to improve fresh produce safety.

• Journal of Dairy Science and Biotechnology
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• v.28 no.2
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• pp.7-11
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• 2010

In recent times, antimicrobial resistance has been a concern because of its relation to national health and food safety. In this study, we reviewed the management of antibiotics and antimicrobial-resistant microorganisms in domestic and foreign countries and analyzed microorganisms and antimicrobial resistance in dairy farms and raw milk. The isolates from dairy farms were Micrococcus spp., Staphylococcus chromogens, Escherichia coli, Bacillus licheniformis, Escherichia coli O157:H7, Pseudomonas plecoglossicida, Enterobacter spp., and Kluyvera intermedia. Rummeliibacillus stabekisii, Paenibacillus badius, Pantoea agglomerans, B. oleronius, B. fusiformis, and B. badius were isolated from feed E. coli and Kurthia gibsonii, from feces and S. pasteuri, S. aureus, S. chromogenes, and Salmonella spp., from raw milk. Pathogens isolated from dairy farms and raw milk were tested for susceptibility to 20 types of antibiotics. E. coli (EAEC) and E. coli O157:H7 (EHEC) isolated from dairy farms, E. coli (EAEC) isolated from feces, and Salmonella spp. isolated from raw milk showed resistance to multiple antibiotics. These results show that antimicrobial-resistant microorganisms should be more effectively managed to improve the safety of dairy farms.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.717-723
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• 2014

A rapid and specific PCR assay for the simultaneous detection of Listeria monocytogenes, Escherichia coli O157:H7, Bacillus cereus, Salmonella spp., and Staphylococcus aureus in foods was developed to reduce the detection time and to increase sensitivity. Multiplex PCR developed in this study produced only actA, fliC, hbl, invA, ileS amplicons, but did not produce any non-specific amplicon. The primer sets successfully amplified the target genes in the multiplex PCR without any non-specific or additional bands on the other strains. The multiplex PCR assays also amplified some target genes from five pathogens, and multiplex amplification was obtained from as little as 1 pg of DNA. According to the results from the sensitivity evaluation, the multiplex PCR developed in this study detected 10 cells/mL of the pathogens inoculated in milk samples, respectively. The results suggested that multiplex PCR was an effective assay demonstrating high specificity for the simultaneous detection of five target pathogens in food system.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1569-1571
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• 2002

The determination of DNA hybridization can apply the molecular biology research, clinic diagnostics, bioengineering, environment monitoring, food science and other application area. So, The determination of hybridization is very important for the improvement of DNA detection system. In this study, we report the characterization of the DNA hybridization by the electricalchemical methods. A new electrochemical biosensor is described for voltammetric detection of gene sequence related to probe oligonucleotide of bacterium Escherichia coli O157:H7. The biosensor involves the immobilization of a 18-mer probe oligonucleotide, which is complemetary to a specific gene sequence related to Escherichia coli O157:H7 on a gold electrode through specific adsorption. The probe oligonucleotide was used to determine the amount of target oligonucleotide in solution using mitoxantrone(MTX) as the electrochemical indicators. The cathodic peak currents $(I_{peak})$ of MTX were linearly related to the concentration of the target oligonucleotide sequence in the range $1[{\mu}M]{\sim}0.1[nM]$. The detection limit of this approach was 0.01[nM]. In addition, these indicators were capable of selectivity discriminating against various mismatching condition.

• Journal of Environmental Health Sciences
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• v.32 no.4 s.91
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• pp.316-323
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• 2006

This study was performed to assess the microbial contamination level for the processing of sandwich products in the middle of Gyeongnam province from December 2004 to January 2005. A total of 85 samples were collected from 5 sandwich shops. These samples were tested sanitary indication bacteria, such as aerobic Plate count(APC), coliforms, and Escherchia coli and pathogenic bacteria such as Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes, and Staphylococcus aureus. As a result of APC and coliform count ranged 0-4.59 $log_{10}$ CFU/(ml, g, 100 $cm^2$, hand) and 0-3.86 $log_{10}$ CFU/(ml, g, 100 $cm^2$, hand), respectively. Especially, the highly contaminated items for APC were confirmed 1.64-4.59 $log_{10}$ CFU/g to employees', raw materials and sandwich in all items. Escherichia coli was isolated from 5 samples. Listeria monocytogenes and Staphylococcus aureus were detected in 1 sample and 11 samples from utensil, raw materials and sandwiches, respectively. However, Escherichia coli O157:H7 and Salmonella spp. were not detected in anywhere. For the production of safety sandwich, education of sanitation for employees, control of raw materials, and continuous monitoring for microorganism will be required.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1230-1238
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• 1999

To identify antimicrobial activities of soybean paste, studies have been carried out with laboratory manufactured soybean paste, traditional and improved type soybean paste purchased on the market. The soybean paste fermented with Aspergillus oryzae and Rhizopus tamari and commercial soybean paste were shown antimicrobial activities for Bacillus cereus, Escherichia coli, Listeria monocytogenes, Staphy lococcus aureus, Streptococcus faecalis, Escherichia coli O157:H7, Bacillus subtilis and Salmonella typhimurium. Non fermented soybean paste did not show antimicrobial activities against Bacillus cereus, Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Streptococcus faecalis. The extract of soybean paste extracted by 80% methanol showed the highest antimicrobial activities of in ethyl acetate fraction and followed butanol fraction, respectively. Antimicrobial activities of traditional and improved type soybean paste were shown against all tested microorganisms and clear zone length of traditional soybean paste was slightly larger than that of improved type. Components of antimicrobial fractions of soybean paste were guessed peptides, 4 hydroxy benzoic acid, benzoic acid by GC MS.

• Journal of Food Hygiene and Safety
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• v.17 no.1
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• pp.36-44
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• 2002

GC-l00X is non-corrosive alkaline ionic water (pH 12). It is composed of hydroxyl radicals and supplemented with xylitol. Its antimicrobial activity was examined against 6 major food-borne pathogens; Staphylococcus aureus FRI 913, Salmonella enterica serova Enteritidis ATCC 13076, S. enterica serova Typhimurium Korean isolate, Vibrio parahaemolyticus ATCC 17803, Escherichia coli O157:H7 ATCC 43894 and Pseudomonas aeruginosa KCTC 1637 at three different temperatures (4$^{\circ}C$, $25^{\circ}C$ and 36$^{\circ}C$) with or without an organic material (2% yeast extract), respectively. The antimicrobial activities showed over 4 log-reductions (1.0$\times$10$^4$CFU/ml reduction) against all pathogens reacted at 37$^{\circ}C$ for 3 hours in the absence of the organic material. The activities showed same results when GC-l00X was diluted with same volume of distilled water or standard hard water (CaCO$_3$300 ppm). Its antimicrobial activity was more effective and quicker in Gram-negative bacteria than Gram-positive bacteria. Its washing efficacy against E. coli O157:H7 exposed to the surfaces of tomatoes (grapes) was compared with that of the other sanitizers such as other kitchen synthetic detergent and 100-ppm chlorine water. For the toxicological evaluation of the sanitizers, viable counts of E. coli O157:H7 penetrated into the core of tomatoes after washing products were also compared. The result revealed that GC-100X stock solution and its 5% diluted solution had similar washing effects to 100-ppm chlorine water and more effective than the other kitchen synthetic detergent. This result indicated that GC- l00X had antimicrobial activity and no toxicological side effects, therefore, could be useful for a new sanitizer to use in flood safety and kitchen hygiene.