• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.53-63
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• 2005

This study was carried out to determine the inhibitory effect of methanol extract from kimchi ingredients against Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus, and Esherichia coli which are pathogenic microorganisms and Aspergillus sp. Penicillium sp. Antimicrobial activity of methanol extracts was tested against bacteria by paper disc method. Antifungal activity of methanol extracts was shown by hyphal growth inhibition ratio. The methanol extracts from all materials were effective against E. coli among them. And the antimicrobial activity of the methanol extracts from ginger and onion were lower than the others. The antifungal activity of the methanol extracts from radish, ginger, and garlic were effective against Aspergillus sp. and Penicillium sp. In the result of identifying antimicrobial effect rate, the methanol extracts from red pepper and radish had more than $40\%$ against S. typhimurium and more than $30\%$ against E. coli. Also the methanol extracts from onion had an high inhibitory effect rate of more than $50\%$ against S. typhimurium and that from garlic had more than $60\%$ against S. aureus. The minimum inhibitory concentration(MIC) of red pepper was examined 500 $\mu$g/mL against L. monocytogenes. This value was the lowest among the others.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.76-81
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• 2008

Currently, natural food colorants and preservatives are being used for their general health benefits. Monascus koji, the product of certain fungi that grow on rice grains, has been added to many foods for coloring and preservation. In this study, the antimicrobial activities of Monascus koji ethanol extracts were investigated. Six Monascus strains (M. araneosus KFRI 00371, M. kaoliang ATCC 46597, M. pilosus IFO 4520, M. purpureus IFO 4482, M. ruber IFO 32318 and M. sp. ATCC 16437) were selected based on their relative intensity of red pigment. Two Monascus extracts, M. kaoliang ATCC 46597 and M. purpureus IFO 4482, displayed antimicrobial activities against Bacillus subtilis, B. cereus, Micrococcus luteus, Staphylococcus aureus and Salmonella typhimurium in concentration-dependent manners. The two extracts showed their strongest antimicrobial activity against S. typhimurium, a cause of food poisoning. Therefore, these results suggest that Monascus koji could be used as a natural food colorant and preservative.

• Journal of Life Science
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• v.12 no.6
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• pp.669-675
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• 2002

Introduction of sliced raw fish meat(SRFM) to fast food business has been considered seriously. However bacteria causing food poisoning should be controlled. Organic acids such as vinegar and lactic acid used in the sauce for SRFM were evaluated for their antibacterial activities. At low concentration levels of vinegar and lactic acid exerted strong antibacterial activities toward Vibriu sp.. In contrast, in case of Salmonella typhimurium and Escherichia coli O157:H7 low anitbacterial activities were observed even at relatively high concentrations. Minimum inhibitory concentrations(MIC) of vinegar for V. vulnificus, V. cholerae non-O1, V. parahaemolyticus, V. mimicus, S. typhimurium and E. coli O157:H7 were 16, 18, 16, 12, 26, and $20{\mu}\ell /m\ell, respertively. MIC of lactic acid for V. vilnificus, V. cholerae non-O1, V. parahaemolyticus, V. mimicus, S. typhimurium and E. coli O157:H7 were 20, 25, 25, 25, 40, and $35{\mu}\ell /m\ell, respectively. In case of vinegar bactericidal concentration upon 10 second contact for V. vulnificus, V. cholerae non-O1, V. parahaenolyticus, V. mimicus and E. coli O157:H7 were 8, 14, 10, 4, and 48%, respectively; however, even at 50% colony of S. typhimurium was observed. In case of lactic acid any colony was observed for V. vulnificus, V. cholerae non-O1, V. parahaemolyticus, V. mimicus, S. typhimurium and E. coli O157:H7 at the concentration of 2, 3, 4, 3, 14, and 17%, respectively. Vinegar and lactic acid of low concentration inhibited the growth of Vibrio sp., food poisoning pathogen in SRFM; in contrast, at high concentration these organic acids inhibited Salmonella sp. and Escherichia sp., food poisoning pathogen in other than SRFM.

• Food Science and Preservation
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• v.14 no.2
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• pp.207-212
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• 2007

The antimicrobial activity of Curcuma aromatica Salab. was investigated. The Curcuma aromatica Salab. extract showed antimicrobial activity against six pathogens tested. These were Listeria monocytogenes ATCC 19115, Pseudomonas fluorescens ATCC 21541,Staphylococcus aureus ATCC 29273, Salmonella typhimurium ATCC 21541, vibrio parahaemolyticus ATCC 17802, and Aeromonas hydrophila KCTC 2358. Antimicrobial activity was alsonoted when the extract was tested against four isolates of Bacillus sp. purified from spoiled tofu. The growth of various pathogens was significantly inhibited (100 10,000-fold) upon growth in tryptic soy broth containing 0.05 0.2%(w/v) Curcuma aromatica Salab. extract(CE), after incubation for 12hr at $37^{\circ}C$. The growth of the four Bacillus isolates was also significantly inhibited in nutrient broth containing 0.05 0.2% CE after incubation for 24hr at $37^{\circ}C$. Although the antimicrobial activity of CE was decreased by heat treatment at temperatures above $80^{\circ}C$, the activity remained relatively high after heat treatment at $121^{\circ}C$ for 15min. The minimum inhibitory concentrations of CE were 0.1 0.3%(v/v culture) for the six pathogens, and 0.2 0.25% for the Bacillus isolates, respectively.

• Microbiology and Biotechnology Letters
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• v.39 no.4
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• pp.390-396
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• 2011

Lactobacillus sakei is known to be the most populous lactic acid bacteria in over-ripened kimchi. Twenty three strains of Leuconostoc species inhibiting the growth of Lb. sakei were isolated from kimchi and amongst these the Leuconostoc mesenteroides strain CK0122 exhibited the highest antagonistic activity against Lb. sakei. The culture supernatant of the strain CK0122 was fractionated by a molecular weight cutter and lyophilized. The fraction with a molecular weight of less than 3,000 Da showed antagonistic activity against Lb. sakei. The antibacterial activity of the active fraction was sensitive to proteinase K treatment, confirming its proteinaceous nature (bacteriocin). The crude bacteriocin was active in the pH range of 4 to 7 and extremely stable after 15 min of heat treatment at $121^{\circ}C$. The crude bacteriocin inhibited the growth of Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Alcaligenes xylosoxydans, Flavobacterium sp., and Salmonella typhimurium.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.445-451
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• 1996

The strain YCH-37, which produces yeast cell wall lytlc enzyme, was isolated from soil. From the microscopic observation, morphological and cultural characteristics, this strain was identified to fungus, Dicyma sp. So, we named this strain as Dicyma sp. YCH-37. The lytic enzyme effectively lysed Salmonella typhimurium among intact living bacteria and Torulopsis, Hansenula, Zygosaccharomyces among intact living yeast, as well as autoclaved yeast strains. The yeast cell wall lytic enzyme was succesively purified to 204 folds with 13% yields through yeast glucan affinity adsorption and DEAE-cellulose column chromatography. The enzyme was identified to monomeric protein with molecular weight of 25,000 daltons from the results of SDS-PAGE and gel filtration. The optimum pH and temperature for the yeast lytic activity were 8.0 and 50$\circ$C, respectively. The enzyme was stable up to 40$\circ$C, and between pH 4.0-pH 10.0.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.253-257
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• 2002

The time-dependent changes of red pigments production in solid-state plant scale fermentor using barley cultured with Monascus sp., instead of rice which was traditionally used, were investigated in this study. A steady increase in the yield of red pigments in barley occurred between the 3rd and 6th days. The optimized conditions (inoculation volume = 6∼8%, initial pH = 6, air supply = 0.6∼0.8 m) promoted the production of red pigments. Short-time steaming of barley (< 20 min) decreased fungal growth and pigments production due to the insufficient gelatiniza-tion. The optical density of the red pigments under the optimized conditions was 120 at 500 ]nm per gram of barley. In addition, the metabolites from the fermented barley with Monucus sp. showed antibacterial effects against Escherichia coli and Salmonella typhimurium. Barley was shown to be one of the best grain sources for solid-state fermentation with Monascu sp., fur obtaining natural pigments and also functional food materials.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.459-464
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• 2019

This study aimed to identify and characterize the antimicrobial activity of prodigiosin produced by Serratia sp. $PDGS^{120915}$ isolated from stream water in Busan, Korea; the identification was performed using phonological, biochemical, and molecular techniques, including 16S rRNA sequence analysis. Prodigiosin from the bacterial culture was purified by high-performance liquid chromatography (HPLC), and its antimicrobial activity and minimum inhibitory concentrations (MICs) were evaluated against 10 intestinal pathogenic gram-positive and negative bacteria. The results revealed that the isolated prodigiosin exhibited high antimicrobial activity against Listeria monocytogenes, Bacillus cereus, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus, and Vibrio parahaemolyticus; further, the isolated prodigiosin showed minimum inhibitory concentrations (MICs) between $3{\mu}g/ml$ and 30 mg/ml, but they were not active against Bacillus subtilis, Enterococcus faecalis, Klebsiella pneumonia, and Escherichia coli. In conclusion, prodigiosin isolated from Serratia sp. $PDGS^{120915}$ showed high antimicrobial activity against intestinal pathogenic bacteria and has potential applications in the development of new antimicrobial agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.470-475
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• 2007

Antibacterial activities of Scutellaria baicalensis Georgi (SBG) extract were examined against spoilage bacteria isolated from commercial tofu and various pathogens such as Listeria monocytogenes ATCC 19115, Pseudomonas fluorescens ATCC 21541. Staphylococcus aureus ATCC 29737, Salmonella Typhimurium ATCC 11806, Vibrio parahaemolyticus ATCC 17802, and Aeromonas hydrophila KCTC 2358. Four kinds of spore forming organisms were isolated from commercial tofu and identified as Bacillus sp. KN-4, Bacillus sp. KN-6, Bacillus sp. KN-10 and Bacillus sp. KN-20 using API CHB kit. The SBG extract showed high antibacterial activities and significantly inhibited the growth of the isolated spoilage bacteria and pathogens. The inhibitory effects against the organisms increased as the concentration of the SBG extract increased. The antimicrobial activities of the SBG extract were maintained markedly after heat treatments $(80^{\circ}C/30\;min,\;100^{\circ}C/30\;min\;and\;121^{\circ}C/15min)$. The minimum inhibitory concentrations (MIC) of the SBG extract against the organisms ranged from 1,000 ppm to 5,000 ppm.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.77-83
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• 2010

The fructus of Crataegus pinnatifida Bunge (CBF) has been used as medicinal and food source in worldwide. In this study, antimicrobial activity of the methanol extract and its sequential organic solvent fractions of CBF against different pathogenic bacteria and fungi, including multidrug resistant Pseudomonas aeruginosa and Candida sp., were investigated. The methanol extract of CBF was active against various gram-positive and gram-negative bacteria, and the ethylacetate and butanol fractions of CBF showed strong antibacterial activity against Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Salmonella typhimurium, Proteus vulgaris, Escherichia coli and various multidrug resistant Pseudomonas aeruginosa with minimal inhibitory concentration of 1.0~7.5 mg/mL. Also the fractions showed anti-Candida activity against C. albicans, C. kruseis and C. geochares. The methanol extract of CBF and its solvent fractions, except n-hexane fraction, did not show any hemolytic activity against human red blood cell up to $500\;{\mu}g/mL$, respectively. The hemolysis in n-hexane fraction at $500\;{\mu}g/mL$ was less than 9.9%. Our results suggest that the CBF could be developed as a potent antibacterial agent, especially for multidrug resistant Pseudomonas aeruginosa.