• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.695-702
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• 2017

This study was carried out to investigate the effects of seed vinegar on antioxidant activity and antimicrobial activities of concentrated blueberry vinegar (CBV). Of the nine strains of yeast and six strains of acetic acid bacteria provided by the Microbial Institute for Fermentation Industry, each strain of yeast (Saccharomyces cerevisiae SRCM 100610, showing the highest ethanol content) and acetic acid bacteria (Acetobacter pasteurianus SRCM 101342, showing the highest total acidity) was selected for production of CBVs. Sugar content, pH, total acidity, total phenolic content (TPC), and browning intensity (280 nm and 420 nm) in CBVs using concentrated blueberry juice were $11.05{\sim}12.70^{\circ}Brix$, 2.63~2.98, 1.65~5.72%, 3.03~4.24 mg/mL, 0.95~1.50, and 0.11~0.20, respectively. Sugar content and total acidity of CBVs increased upon addition of seed vinegar, whereas pH, TPC, and browning intensity decreased. Of all CBVs with various additions of seed vinegar, the control showed the lowest $EC_{50}$ values in DPPH radical scavenging assay, ABTS radical scavenging assay, and reducing power (23.80, 19.48, and 79.21 dilution factor, respectively), whereas the 40% seed vinegar group showed the highest clear zone diameter values for Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus (4.31, 4.59, 5.81, and 3.97, respectively). Antioxidant activities of CBVs were closely correlated with their TPC, browning intensity at 280 nm, pH, and total acidity values, showing correlation determination coefficient ($R^2$) values higher 0.82. However, antimicrobial activities of CBVs were closely correlated with their pH and total acidity values, showing higher $R^2$ values more than 0.92. These results suggest that CBVs using concentrated blueberry juice, S. cerevisiae SRCM 100610, and A. pasteurianus SRCM 101342 may be useful as potentially functional foods for enhancing health.

• Journal of Life Science
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• v.12 no.6
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• pp.803-811
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• 2002

The present study was carried out for research and development of natural antimicrobial from extract of Stachys sieboldii MIQ against food borne bacteria. The hexane extract of Stachys sieboldii MIQ at 250$\mu\textrm{g}$/$m\ell$ per disc showed 15 ~ 20 mm inhibition zone against gram positive and gram negative barteria. Minimum inhibitory concentration (MIC) of hexane extract was 250${\mu}g$/$m\ell$against Bacillus cereus, 250~500${\mu}g$/$m\ell$against Listeria monocytogenes, 500${\mu}g$/$m\ell$ against Staphylococcus aureus, Psedomonas aeruginosa. Observation by transmission electron microscope, showed that disruption of the cell wall assumed to be due to the bactericidal activity. In addition, the membrane integrity of the sensitive cells was disrupted by exposure to Stachys sieboldii MIQ extract on the D-$\beta$-galatosidase activity as substrate of O-nitrophenol-$\beta$-D-galacto-pyranoside. The hexane extract of Stachys sieboldii MIQ was very stable on the pH and thermal stability.

• Korean Journal of Veterinary Service
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• v.28 no.3
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• pp.215-223
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• 2005

The bacteria on the surface of slaughtered meat was monitored to investigate the relationships between microbiological quality and sanitation management in slaughter process of cattle and pig. It was conducted to evaluate the microbiological quality on the surface of slaughtered beef and pork in Seoul from January to December 2004. Two hundred and thirty three beef and 233 pork carcasses were surveyed on generic E coli counts and standard plate count for microbiological quality and Salmonella spp, Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens and E coli O157: H7 as pathogenic microorganisms. The prevalence of the excellent or good grade $(10^4\;CFU/cm^2)$ in beef and pork carcasses were $100\%\; and\;99.2\%$, respectively. The frequency of beef carcasses with less than $10^2\;CFU/cm^2$ of generic I coli counts was $100\%$, while that of pork carcasses was $99.6\%$. Of 233 beef carcasses, $1(0.42\%)$ was contaminated with L monocytogenes and $6(2.58\%)$ with C perfringens. Of 233 pork carcasses, $11(4.72\%),\;2(0.86\%),\;and\;2(0.86\%)$ were contaminated with L monocytogenes, C perfringens, and S aureus, respectively, Salmonella spp and E coli O157:H7 were not detected with all of the beef and pork carcasses. In conclusion, this study emphasized the Importance of relationship between microbiological quality and sanitation management in slaughter process of cattle and pig, in abattoirs.

• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.147-153
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• 2009

Salmonella species are the most important etiologic agents of food-borne acute gastroenteritis. The most common serotypes isolated from humans are Salmonella enterica serotype Typhimurium (S. Typhimurium) and S. Enteritidis. Traditional detection methods for Salmonella are based on cultures using selective media and characterization of suspicious colonies by biochemical and serological tests. These methods are generally time-consuming and not so highly sensitive. Recently, the polymerase chain reaction (PCR) has been used as a highly sensitive, specific, and rapid test for the presence of pathogenic bacteria. In this study, a multiplex PCR (m-PCR) was used to detect S. Typhimurium and S. Enteritidis. We selected m-PCR target genes, which were the spv (virulence plasmid specific for S. Enteritidis) and sefA (S. Enteritidis fimbrial antigen) genes, fliC (H1-i antigen specific for S. Typhimurium) and a randomly cloned sequence specific for the genus Salmonella. With m-PCR, random sequence was detected from all strains of Salmonella spp, spv and sefA were detected from all strains of S. Enteritidis (100%), and fliC was detected from all strains of S. Typhimurium (100%). This assay indicate that the specificity of the m-PCR make them potentially valuable tools for detection of S. Typhimurium and S. Enteritidis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.535-541
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• 2018

This study evaluated the sanitary state of seawater and shellfish in Yongnam-Gwangdo area from January 2014 to December 2016. The sampling stations for sanitary survey in Yongnam-Gwangdo area were composed of 41 seawater stations and 5 oyster Crassostrea gigas stations. The samples were collected monthly at each station. Shellfish-borne disease is associated with bacteria and viruses in the presence of fecal coliforms. Bacteriological pollution levels of shellfish increase with seawater quality. Therefore, fecal coliforms are very important criteria for evaluating the safety of fisheries in coastal areas. The geometric mean and the estimated 90th percentile ranges of total and fecal coliforms for seawater were 1.8-11.7, 2.8-233.6, <1.8-6.7 and 1.8-100.2 MPN/100 mL, respectively. The range of E. coli levels for oysters was <20-1,300 MPN/100 g. Based on various standards, the sanitary condition in Yongnam-Gwangdo area was evaluated as follows: clean area (Korean criteria), conditionally approved area (US criteria) and class B (EU criteria).

• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.93-100
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• 2005

This research was performed to investigate the possibilities of industrial usage of camellia (Camellia japonica L.) by examining the antioxidant and antimicrobial effects of methanol extract with different sections. Content of total phenolics, DPPH radical scavenging activities and antibacterial activity of young leaf, mature leaf, flower bud, flower, bark, and seed of camellia were compared in vitro experimental models. Total phenolics was contained the higher in young leaf (74.62 mg), flower bud (65.02 mg) and flower (62.42 mg) but less than 20.95 mg per 100 g of dry weight in other parts of Camellia japonica L. And effects of antioxidant measured by DPPH radical scavenger activity ($RC_{50}$, reduce concentration 50%), was shown higher $7.16{\sim}18.14\;{\mu}g/m{\ell}$ in methanol extract of young leaf, flower bud and flower than $61.23\;{\mu}g/m{\ell}$ of BHT as a chemical oxidant. Also, the antimicrobial activity of Camellia japonica L. extracts determined using a paper disc method against food-borne pathogen and food spoilage bacteria, the young leaves extracts showed the most active antimicrobial activity against 7 kinds of harmful microorganisms. Flower bud extracts showed the highest antibacterial activity against P. aeruginosa and Enterobacter spp. C1036. In addition, the minimum inhibitory concentration (MIC) of young leaf extract against B. subtillis,S. fradiae,S. aureus,E. coli,P. aeruginosa, Enterobacter spp. C1036, and S. typhimurium were revealed 1 to 15 ${\mu}g/m{\ell}$. As a result, antimicrobial activity of camellia extracts was shown higher gram positive bacteria than gram negative bacteria.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.437-442
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• 2014

Foodborne illness due to the consumption of contaminated raw strawberries is a continuing food safety concern. This study investigated and evaluated contamination levels of bacteria on strawberries at farms stage to evaluate potential hazards associated with fresh strawberries. A total of 315 samples, 105 samples from 5 sampling sites (A to E) of 21 farms and 210 samples from 1 sampling site of 6 farms, was collected every month for four months and analyzed to enumerate aerobic bacterial counts, Coliforms/E. coli, Bacillus cereus and Staphylococcus aureus. In addition, the prevalence study of five pathogens (S. aureus, E. coli, E. coli O157:H7, Salmonella spp. and Listeria monocytogenes) was performed on each sample. Aerobic bacterial counts ranged from 0.48 to 6.36 Log CFU/g, with the highest bacterial cell counts recorded for D and E sites. Coliforms were detected in 71 samples (22.5%) with a minimum of 0.48 cfu/g and a maximum of more than 4 Log CFU/g. B. cereus was detected in 98 samples (31.1%) among total samples analyzed. S. aureus was detected in 2 samples with a minimum of 0.48 Log CFU/g and a maximum of 1.38 Log CFU/g. E. coli, E. coli O157:H7, Salmonella spp. and L. monocytogenes were not isolated from any of the samples. The microbial contamination levels of strawberries determined in this study may be used as the fundamental data for microbiological risk assessment.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.328-335
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• 2010

The aim of our study was to develop a new starter culture for fermented milk. Polymerase chain reaction screening of 103 acid-producing isolates from Kimchi identified 72 Lactobacillus strains. The ability of the strains to inhibit the growth of the food-borne human pathogens (Escherichia coli, Salmonella Enteritidis, Staphylococcus aureus) was measured, using a conventional paper disk method. Among the 72 strains, strain LHC52 displayed potent antagonistic activity. Use of 16S rDNA sequencing and the API 50CHL system identified the strain as Lactobacillus plantarum and it was designated L. plantarum LHC52. Biochemical analyses revealed especially high antibacterial activity against E. coli. Yogurt produced using L. plantarum LHC52 did not show different microbiological and physicochemical properties compared to conventionally-prepared yogurt, implicating L. plantarum LHC52 as a useful, potently antibacterial starter culture for yogurt preparation.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.647-651
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• 2013

Animal manure compost is a commonly used fertilizer in organic vegetable and fruit production in Korea. However, livestock manure compost produced from animal feces can contain a lot of the non-pathogenic and pathogenic bacteria. Of particular concern are bacteria causing human food-borne illness such as Escherichia coli O157:H7 and Listeria monocytogenes. The objective of this study was to investigate effect of temperature on survival of E. coli O157:H7 and L. monocytogenes in livestock manure compost. Commercial livestock manure compost (manure 60%, sawdust 40%) was inoculated with E. coli O157:H7 and L. monocytogenes. Compost was incubated at four different temperatures (10, 25, 35, and $55^{\circ}C$) for 20 weeks. Samples were taken every week during incubation depending on the given conditions. E. coli O157:H7 persisted for up to 1 day in livestock manure compost at $55^{\circ}C$, over 140 days at $10^{\circ}C$, 140 days at $25^{\circ}C$, and 120 days at $35^{\circ}C$, respectively. L. monocytogenes persisted for up to 1 day in livestock manure compost at $55^{\circ}C$ and 140 days at $10^{\circ}C$, 70 days at $25^{\circ}C$, and 40 days at $35^{\circ}C$, respectively. The results indicated that E. coli O157:H7 and L. monocytogenes persisted longer under low temperature condition. E. coli O157:H7 survived longer than L. monocytogenes at three different temperatures (10, 25, and $35^{\circ}C$). The results are being used to develop guidelines on the management of manure to reduce the risks of E. coli O157:H7 and L. monocytogenes transmission to foods produced in the presence of animal waste.

• Korean Journal of Veterinary Service
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• v.35 no.3
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• pp.223-230
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• 2012

This study was carried out to investigate the heavy metal and microbiological hazards on by-products (liver, omasum, small intestines) of cattle. From April to October in 2011, one hundred and twenty samples were equally collected from slaughterhouse and meat by-product markets in Incheon city. The total bacteria counts and E. coli count were applied to assess the microbiological quality. Food borne bacteria including Salmonella spp., Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens and E. coli O157:H7 were also determined. The results were obtained as follows: The undesirable grade (more than $10^5\;CFU/cm^2$) was detected in the by-product from 18.3% (slaughterhouse) and 23.3% (by-product markets). The frequency of generic E. coli (more than $10^2\;CFU/cm^2$) from the slaughterhouse was 20.0%, whereas that of the meat by-product markets was 26.7%. Of the samples from slaughterhouse, 3 (5.0%), 5 (8.3%), and 12 (20.0%) samples were contaminated with Salmonella spp, S. aureus, and C. perfringens, respectively. S. aureus and C. perfringens were also detected in 6 (10.0%) and 25 (41.7%) samples in the meat by-product markets, respectively. Nine of 11 S. aureus isolates harbored toxin gene. However, the cpe gene of C. perfringens was not detected among the 37 isolates. The detection rate was higher in August than in February, April and June. The levels of Cd and Pb in all the samples tended to be low (<0.2 mg/kg). This preliminary data could be used for legislation on the regulation and control of microorganism and heavy metal in by-products of cattle.