• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.526-531
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• 2006

Minimum inhibition concentration(MIC), growth inhibition activity, and colony forming inhibitory activity of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enterifidis and Serratia marcescens were tested. MIC of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enteritidis and Serratia marcescens was 12.5, 12.5, 12.5, 50, 50, 100ppm, respectively. Growth inhibition concentration of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enteritidis and Serratia marcescens was below 1.0, 6.25, below 1.0, 6.25, 25, 25ppm, respectively. Colony forming inhibitory activity of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enteritidis and Serratia marcescens was 93.9, 94.0, 99.9, 4.4, 82.7, 86.4%, respectively. Colony forming inhibitory activities of grapefruit seed extract against Gram positive bacteria were higher than that against Gram negative bacteria.

• The Korean Journal of Food And Nutrition
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• v.21 no.1
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• pp.15-21
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• 2008

In this study, the minimum inhibition concentration(MIC), growth inhibition activity, and colony forming inhibitory activity of water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae and Salmonella enteritidis were tested. The MICs of the water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 312.5 ppm, below 156.3 ppm, 625 ppm, 10,000 ppm, above 10,000 ppm, 10,000 ppm, above 10,000 ppm, above 10,000 ppm, 10,000 ppm, and above 10,000 ppm, respectively. The growth inhibition concentrations against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, and Klebsiella pneumoniae were 156.3 ppm, below 156.3 ppm, 625 ppm, 5,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, and 5,000 ppm, respectively. However, 10,000 ppm did not inhibit the growth of Salmonella enteritidis. Finally, the colony forming inhibitory activities against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 98.0%, 99.8%, 69.8%, 98.1%, 62.0%, 63.1%, 79.5%, 61.9%, 79.6%, and 0.0%, respectively.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.2
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• pp.182-187
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• 2005

This study was performed to investigate the antimicrobial effect of the Viscum album var. coloratum extracts against food-borne pathogens. First, the Viscum album var. coloratum was extracted with methanol at room temperature and the fractionation of the methanol extracts was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol, respectively. The antimicrobial activity of the Viscum album var. coloratum extracts was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The petroleum ether extracts of Viscum album var. coloratum showed the highest antimicrobial activity against Bacillus cereus and Shigella dysenteriae. Synergistic effect in inhibition was observed when Viscum album var. coloratum extract was mixed with Perillae folium extract as compared with each extract alone. Finally, the growth inhibition curves were determined by using petroleum ether extracts of Viscum album var. coloratum against Bacillus cereus and Shigella dysenteriae. The petroleum ether extract of Viscum album var. coloratum had strong antimicrobial activity against Bacillus cereus at the concentration of 5,000 ppm. At this concentration, the growth of Bacillus cereus was retarded more than 24 hours and up to 12 hours for Shigella dysenteriae. In conclusion, the petroleum ether extracts of Viscum album var. coloratum inhibit efficiently Bacillus cereus and Shigella dysenteriae.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.188-193
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• 2001

To evaluate antimicrobial activities of chongkukjang slime fermented by different strains, growth characteristics were compared using various standard microorganisms with addition of chongkykjang slime. Chonghkjang slime was prepared by fermenting cooked soybean after inoculating with Bacillus circulans K-1, Baciilus spp N-1 and Bacillus subtilis CH-1, respectively. Significant antimicrobial activity was observed by chongkukjang slime on gram positive bacteria (Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Micrococcus luteus), gram negative bacteria(Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas fluorescens), and yeast (Pichia membranaefaciens, Saccharomyces cerevisiae, Candida albicans). In case of B. cereus growth inhibition of 80% was achieved by the addition of chongkukjang slime; on the contrary, to Escherichia coli O157:H7 only 20% inhibition was observed. Slime from Bacillus subtilis CH-1, in particular, inhibition of 40% toward bacteria and yeast, whereas slime from Bacillus circulans K-1, Bacillus spp N-1 showed only 20% inhibition.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.44-55
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• 2016

Bacillus cereus is a gram-positive, rod-shaped, spore-forming bacterium that has been isolated from contaminated fermented soybean food products and from the environment. B. cereus produces diarrheal and emetic toxins and has caused many outbreaks of foodborne diseases. In this study, we investigated whether B. amyloliquefaciens RD7-7, isolated from rice doenjang (Korean fermented soybean paste), a traditional Korean fermented soybean food, shows antimicrobial activity against B. cereus and regulates its toxin gene expression. B. amyloliquefaciens RD7-7 exhibited strong antibacterial activity against B. cereus and inhibited the expression of B. cereus toxin-related genes (groEL, nheA, nheC, and entFM). We also found that addition of water extracts of soybean and buckwheat soksungjang (Korean fermented soybean paste made in a short time) fermented with B. amyloliquefaciens RD7-7 significantly reduced the growth and toxin expression of B. cereus. These results indicate that B. amyloliquefaciens RD7-7 could be used to control B. cereus growth and toxin production in the fermented soybean food industry. Our findings also provide a basis for the development of candidate biological control agents against B. cereus to improve the safety of fermented soybean food products.

• Korean Journal of Food Science and Technology
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• v.48 no.6
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• pp.569-573
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• 2016

The effectiveness of various additives in reduction of an unpleasant odor and inhibition of Bacillus cereus growth in Cheonggukjang (CKJ) was investigated. Sensory evaluations of unpleasant odor intensity and taste preference for CKJ were conducted with a 5-point scale. Raw CKJ was rated to have the highest unpleasant odor intensity, followed by CKJ-salt, CKJ-wood vinegar salt, CKJ-red pepper seed oil, and CKJ-bamboo salt in the given order. The test panel had a greater preference for CKJ-red pepper seed oil than for the other CKJ products. The addition of bamboo salt to CKJ was the most effective in inhibition of B. cereus growth in comparison to the other three additives. Volatile compounds in CKJ and CKJ-bamboo salt were identified by GC/MS analysis. 1-Ethoxy-1-methoxy-ethane was responsible for the pleasant odor and its level significantly increased in CKJ-bamboo salt. Consequently, adding bamboo salt to CKJ not only masked and reduced the unpleasant odor, but also inhibited B. cereus growth in CKJ.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.163-167
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• 2010

Bacillus subtilis 168 secreted antimicrobial substance(s) into culture medium and culture supernatant inhibited growth of some Gram positive bacteria. B. cereus and Listeria monocytogenes were the most sensitive organisms. The antimicrobial activity was destroyed when culture supernatant was treated by protease and proteinase K, indicating the proteinous nature of the substance (bacteriocin). The molecular weight of the bacteriocin was estimated to be 5 kDa by Tricine SDS-PAGE. B. cereus ATCC 14579 cells were killed when exposed to the bacteriocin, indicating that the mode of inhibition was bacteriocidal. These results show that B. subtilis 168 could be useful as a starter for fermented foods such as cheonggukjang where B. cereus contamination is a major concern.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.998-1002
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• 2003

Agricultural foodstuffs, usually consumed without sterilization, are frequently contaminated with foodborne pathogen B. cereus. Ethanol and sodium chloride were used to inhibit this pathogen for its effective control. Though five minutes of exposure to 20% ethanol did not inhibit the growth of B. cereus, inhibition was detected to 30% ethanol solution. As exposed longer, B. cereus was more effectively inhibited than E. coli and S. typhimurium. B. cereus, E. coli and S. typhimurium were not inhibited when exposed in a 10% sodium chloride solution for five minutes. However, these bacteria were inhibited with a combination of 10% sodium chloride and 20% ethanol solution for five minutes. Much synergistic growth inhibition on B. cereus was found at the treatment. Its viable count was reduced from $10^8cfu/ml$ to $10^2cfu/ml$ after five minutes and showed no count after ten minutes. This trend was also confirmed for the wild types of B. cereus. This method may be applied for the effective pre-treatment of many agricultural foodstuffs, especially uncooked foodstuffs, without the hazards that accompany special sanitizers and the nutritional loss from harsh sterilization.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.200-204
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• 1991

Certain parts of 36 kinds of plant were extracted by 75% ethanol and water. The extracts were tested their microbial inhibition activities against several food spoilage microorganisms, Bacillus subtilis, Lactobacillus plantarum, Leuconostoc mesenteroides, Pseudomonas fluorescens, Bacillus cereus and Saccharomyces cerevisiae. The ethanol extract of amur cork was shown inhibitory effect on all 6 species of the microorganisms tested. Chinese pepper, sesame cake, gromwell and oak were on 5 species except S. cerevisiae or P. fluorescens and bamboo leaves, lycopi herba, paulownia and rigida were on 4 species. In general amur cork exhibited the strongest inhibition with a few exceptions on certain species. By disc diffusion method, the ethanol extract of leaf mustard showed the highest inhibition effect on B. subtilis, amur cork on L.plantarum, L. mesenteroides and B. cereus, and amur cork and gallnut on P. fluorescens. Mostly the ethanol extracts in comparison with water extracts showed higher inhibition in most of plants but a few exhibited higher in water extracts.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.5
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• pp.472-478
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• 2004

In this study, Perilla frutescens wh~ch has been used as a folk remedy was investigated its antimicrobial activity. First, the Perilla frutescens was extracted with methanol at room temperatures, and fractionation of the methanol extracts from Perilla frutescens was carried out by using petroleum ether, chloroform, and ethyl acetate, respectively. The antimicrobial activity. of the. Perilla frutescens extracts was determined using a paper disc method and the growth inhibition curve was determined using methanol extracts of Perilla frutescens against Salmonella enteritidis and Bacillus cereus. The methanol extract of Perilla frutescens showed strong antimicrobial activity against Bacillus cereus at the concentration of 1.000 ppm. The 4,000 ppm of methanol extract from Perilla frutescens. retarded the growth of S. enteritidis and Bacillus cereus up to 72 hours.