• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.683-687
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• 2004

Raw beefs used fer Jangzorim production were evaluated fur contamination of pathogenic bacteria and microorganisms related to spoilage and food safety. Eleven groups of mesophilic, psychrotrophic, and anaerobic microorganisms, and total coliforms were selected to evaluate degree of food contamination. Nine strains including Bacillus cereus, Clostridium botulinum, C. perfringens, and Listeria monocytogenes were selected to evaluate incidences of pathogenic bacteria. Raw beefs harbored large populations of microorganisms, which decreased greatly after heat treatment. Psychrotrophic microorganisms were found to be more abundant than other microorganisms. B. cereus, C. perfringens, and L. monocytogenes were isolated from raw beefs, whereas C. botulinum, Escherichia coli O157:H7, Salmonella spp., Shigella spp., Staphylococcus aureus, and Yersinia enterocolitica were not isolated. Isoiates from Cereus selective agar, clostridium Perfringens agar, and Oxford agar were in 99.8, 99.9 and 98.6% agreements with B. cereus, C. perfringens, and L. monocytogenes at species level, respectively. B. cereus produced enterotoxin with CRET-RPLA method, whereas C. perfringens did not produce enterotoxin with PET-RPLA method.

• Food Science of Animal Resources
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• v.22 no.2
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• pp.164-171
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• 2002

The purpose of this study was to evaluate inhibitory activity of a bacteriocin mixture from lactic acid bacteria(LAB) against foodborne pathogens. Each bacteriocin solutions were prepared by growing nine strains of bacteriocin producers in MRS broth for 18~24 h followed by centrifugation(8000$\times$g, 20 min, 4$^{\circ}C$). Bacteriocins were purified from ammonium sulfate precipitation and were resuspended in 50 mM phosphate buffer(pH 7.0). Nine bacteriocins were mixed together and then allowed to freeze at -2$0^{\circ}C$. The mixture of nine bacteriocins showed enhanced inhibitory activity compared to each of bacteriocins and inhibited the Gram negative pathogens including Escherichia coli 0157:H7, Klebsiella pneumoniae, Pseudomonas chlororaphis and Shigella sonnei. The mixture of bacteriocin solutions was significantly lower than controls when a freeze-dried bacteriocin mixture was added to frank sausage, Mozzarella cheese and pork loin. With addition of bacteriocin mixture, total mesophilic bacteria in pork loin were constant over storage period, whereas total mesophilic bacteria in Mozzarella cheese and frank sausang slightly increased. Total viable cells of control group increased during storage without bacteriocin treatment. Volatile base nitrogen content of pork loin during storage also increased significantly without bacteriocin treatment. The bacteriocin mixture was capable of inhibiting pathogenic and spoilage microorganisms and extending the shelf-life of cheese and meat products during storage.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.109-112
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• 1999

Aerobic plate counts(APC) gram-negative bacterial counts (GNC) and sensory evaluations on chic-ken carcasses during retail and refrigerated storages (3$\pm$1$^{\circ}C$ and 1$0^{\circ}C$) were evaluated. APC and GNC on whole chicken in retail store after storage of 7 days at 3$\pm$1$^{\circ}C$ increased to 3.11 and 3.89 log units com-pared to the initial controls. APC and GNC on whole chicken after storage of 7 days at 1$0^{\circ}C$ increased to 5.43 and 5.03 log units. Sensory scores of chicken carcasses obtained from retail store were in the "liked less" category after storage of 7 days compared to fresh controls. These results indicated that chicken carcasses during refrigerated (1$0^{\circ}C$) storages rapidly allowed the growth of aerobic spoilage bacteria dur-ing storage period which cluld not be microbiologically acceptable after of 7 days of 7 days.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.322-327
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• 2020

Abortive infection systems (Abi) are phage resistance systems that can be prophage-encoded. Here, two genes encoding an Abi system were identified on a prophage sequence contained by the chromosome of the Levilactobacillus brevis strain UCCLBBS124. This Abi system is similar to the two-component AbiL system encoded by Lactococcus lactis biovar. diacetylactis LD10-1. The UCCLBBS124 prophage-derived Abi system (designated here as AbiL₁₂₄) was shown to exhibit specific activity against phages infecting L. brevis and L. lactis strains. Expression of the AbiL₁₂₄ system was shown to cause reduction in the efficiency of plaquing and cell lysis delay for phages of both species.

• Journal of Nutrition and Health
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• v.36 no.2
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• pp.147-153
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• 2003

In this study, Artemisia capillaries, which has been used as a folk remedy, was investigated for its antimicrobial activity. First, the Aremisia capillaris was extracted with methanol at room temperature, and fractionation of the methanol extracts from Artemisia capillaris was carried out using petroleum ether, chloroform, and ethyl acetate. Second, the antimicrobial activity of the Artemisia capillaris extracts was determined using a paper disc method and minimum inhibitory concentration of ethyl acetate extracts from Artemisia capillaris against food-borne pathogens and food spoilage bacteria was measured. Finally, the growth inhibition curve was determined using ethyl acetate extracts of Artemisia capillaris against Staphylococcus aureus and Salmonella typhimurium. The ethyl acetate extract of Artemisia capillaris showed strong antimicrobial activity against S. typhimurium at a concentration of 1,000 ppm. The 3,000 ppm of ethyl acetate extract from Artemisia capillaris retarded the growth of S. aureus and S. typhimurium for up to 6 hours.

• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.306-311
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• 2004

This study was performed to investigate the antimicrobial effects of Portulaca oleracea extracts against food-borne pathogens. First, the Portulaca oleracea was extracted with methanol at room temperature, and then further fractionated by using petroleum ether, chloroform, ethyl acetate and methanol, respectively. The antimicrobial activity of the Portulaca oleracea extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of Portulaca oleracea showed the highest antimicrobial activity against Staphylococcus aureus and Shigella dysenteriae. There was also a synergistic effect of the combined extracts of Portulaca oleracea and Indigofera kirilowii as compared to each extract alone. Finally, the growth inhibition curve of ethyl acetate extracts of Portulaca oleracea against Staph­ylococcus aureus and Shigella dysenteriae was determined The ethyl acetate extract of Portulaca oleracea showed strong antimicrobial activity against Staphylococcus aureus at the concentration of 4,000 ppm. The 4,000 ppm of ethyl acetate extract from Portulaca oleracea, retarded the growth of S. aureus by more than 24 hand Shigella dysenteriae up to 12 h at $37^{\circ}C$.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.311-316
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• 2005

This study was performed to investigate the antimicrobial effect of Sophora angustifolia extracts against food-borne pathogens. First, Sophora angustifolia was extracted with methanol at room temperature, and the methanol extracts from Sophora angustifolia were fractionated using petroleum ether, chloroform, ethyl acetate, and methanol. The antimicrobial activity of the Sophora angustifolia extracts was determined using the paper disc method against food-borne pathogens and food spoilage bacteria. The methanol extracts of Sophora angustifolia showed the highest antimicrobial activity against Staphylococcus aureus and Salmonella typhimurium. A synergistic effect was found in the combined extracts of Sophora angustifolia and Portulaca oleracea, compared to the activity of each extract alone. Finally, the growth inhibition curve was determined using the methanol extracts of Sophora angustifolia against Staphylococcus aureus and Salmonella typhimurium. The methanol extract of Sophora angustifolia showed strong antimicrobial activity against Staphylococcus aureus at a concentration of 5,000 ppm. The 5,000 ppm methanol extract from Sophora angustifolia retarded the growth of S. aureus for more than 24 hours and of Salmonella typhimurium for up to 12 hours.

• Journal of Integrative Natural Science
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• v.4 no.1
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• pp.15-22
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• 2011

In this study, liquid with carbonized artemisia was developed for the first time that can be used as food additives and outside medicinal agents by burning artemisia species such as Artemisia dubia wall, Artemisia capillaris Thunb, Artemisia montana (Nakai) Pamp), Artemisia keiskeana Miq, Leonurus Japonicus Houtt. etc. In addition, edibility of recovered liquid with carbonized artemisia was verified by comparing the contents according to each ingredient with common refined pyroligneous liquid through the analysis of 9 kinds of organic acid by the species of artemisia, methanol and ethanol. Besides, the result of antimicrobial activities on six kinds of food spoilage and food poisoning bacteria observed by paper disc method for liquid with carbonized artemisia indicated that those two liquids showed strong antimicrobial. At the concentration of 1.5 mg/disc, clear zone for S. sonnei and S. aureus, L. monocytogenes was 13~16 mm, and they showed stronger antimicrobial activities than other strain.

• Korean journal of food and cookery science
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• v.17 no.6
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• pp.565-570
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• 2001

Soibirhym(Portulace oleracea) was extracted by methanol and its antimicrobial activities against food spoilage or foodborne disease microorganisms were investigated by the paper disc method. The microorganisms used in this experiment included 5 species of bacteria(Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Klebsiella Pneumoniae, Staphylococcus aureus) and 3 species of fungi(Fusarium solani, Aspergillus flavius, Penicillium citreonigrum). Soibirhym showed high antimicrobial activites against P. citreonigrum, P. aeruginosa and K. pneumoniae. Minimum inhibitory concentrations(MICs) on S. aureus, P. citreonigrum and K. pneumoniae were 200, 200 and 250 mg/㎖, respectively. In the methanol extracts from Soibirhym, 147 kinds of compound were separated by GC/MS. The extraction yields of phenolics, furans, alcohols, acids and esters, ketones, aldehydes, and miscellaneous compounds were 7.43%, 6.13%, 2.20%, 41.06%, 9.21%, 0.15% and 1.08%, respectively. Some antimicrobial compounds such as 2,3-dihydro-benzofuran, 4-hydroxy-3-methoxy-benzoic acid, 4-hydroxy benzeneethanol were detected in the methanol extract.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.116-122
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• 1990

In order to improve the shelf life of Tofu, the effect of calcium chloride or acetic acid as coagulants were investigated for microbial and physicochemical changes during the storage in different kinds of soaking solution. The soaking water of Tofu prepared from calcium chloride was found to be spoiled after 15-17 hours of storage at $30^{\circ}C$, by reaching the bacteria count to 10million per ml. The shelf life of the Tofu prepared from acetic acid was better than those prepared by calcium chloride. For the effect of soaking solution on storage life, soaking Tofu in 0.1% acetic acid was found to be more effective than soaking in other solutions of 3% NaCl or 0.1% K-sorbate. The optical density of soaking solution of Tofu increased in proportion to spoilage, and in case of soaked Tofu in 3% sodium chloride and 0.1% K-sorbate solution, it greatly increased. Titratable acidity, and amino nitrogen contents in soaking solution increased as spoilage of Tofu progressed, but pH decreased the early period, one or two days, of stored Tofu and then increased.