• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.823-826
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• 1997

The EtOAc extracts from needles of Pinus densiflora showed antimicrobial activities against bacteria, yeast and fungi. The antimicrobial principle was successively purified by solvent fractionation, silica gel adsorption column chromatography and Sephadex LH-20 column chromatography. The active substance was further purified by HPLC using $C_{18}$ column. The active substance was identified as trans-cinnamic acid by MS, $^{1}H-NMR\;and\;^{13}C-NMR$. The amount of cinnamic acid was $9.27\;{\mu}g$ Per gram of fresh needle of Pinus densiflora.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.993-999
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• 1998

Methanol extract of roots of Amblytropis pauciflora Kitagawa showed the antimicrobial activity to three test strains. Antimicrobial spectra of various extracts of Amblytropis pauciflora Kitagawa were tested against 24 strains of bacteria and fungi. The crude methanol extract inhibited the growth of 12 strains of bacteria and Asp. fumigatus with the exception of yeasts. The properties of the antimicrobial substance were very stable under heat(at 12$0^{\circ}C$), acid(pH 3.0) and alkali(pH 11.0) treatment. Only the root harvested in spring showed the antimicrobial activity. Among the components extracted by butanol, ginseng saponin Rg1 and various saponin-like materials were detected by TLC analysis using a plate of silica gel 60F254. The antimicrobial compound was purified by methanol extraction, activated charcoal column chromatography, Sep-pak(C18) pretreatment and reverse phase HPLC. The purified compound was detected at 13.520 min as a single peak(about 98% purity) through the HPLC analysis.

• Animal cells and systems
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• v.12 no.1
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• pp.41-46
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• 2008

A bacterium strain called Bacillus coagulans was isolated from an industrial wastewater drainage and selected for its antimicrobial activities against bacteria and fungi. Characterization studies strongly suggested that this strain is Bacillus coagulans. Antimicrobial activity was found against gram-positive, gram-negative bacteria and yeast strain. Maximal activity was observed after 24 h when incubated at $30^{\circ}C$ and pH 8. The activity was found to be stable at $75^{\circ}C$ for 30 min and at pH range of 2-12. Analysis of the antimicrobial compound by SDS-PAGE suggested a molecular mass of approximately 7.5 KDa. The substance was characterized as a bacteriocin, because of its proteinaceous nature and low molecular weight. Our bacteriocin could potentially be used as a food preservative, because of its thermostable property and broad antimicrobial spectrum.

• YAKHAK HOEJI
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• v.43 no.4
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• pp.419-422
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• 1999

In order to develop a antimicrobial agent, dried Sophora flavescens Ait. was extracted with several solvents, and than antimicrobial activity was investigated. The minimal inhibitory concentration (MIC) of the extracted substance against microorganisms were also examined. Antimicrobial activity of the initial methanol extract from the sample was the strongest compared to those of other solvent extracts such as $H_2O$, n-hexane, chloroform, ethyl acetate and methanol. The methanol extract had strong growth inhibition activity against gram-postive bacteria (MIC, $25~50{\;}{\mu\textrm{g}}/ml$) such as B. subtilis. Among gram-positive bacteria tested, B. subtilis was the most susceptible to the extracted substance. The antimicrobial activity of the methanol extract from the sample had strong growth inhibition activity against gram-negative bacteria such as P. aeruginosa (MIC, $25{\;}{\mu\textrm{g}}$/ml).

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.90-94
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• 2013

A new Bacillus strain designated as MP56 producing antimicrobial substance has been isolated from the mud flat of Korea. The strain MP56 was found to exhibit broad spectrum of antimicrobial activity against Gram-positive pathogenic microorganisms and MDR (multi drug resistant) strains. The 16S rRNA sequence revealed that the MP56 was closely related to Bacillus subtilis with 99.93% homology. The optimal medium composition for production of antimicrobial substance in the B. subtilis MP56 were 1% mannitol, 1% oat meal, 0.01% $CaCl_2$. Antimicrobial activity of the culture broth against different pathogenic strains was assessed using the antimicrobial spectrum. The result suggests that Bacillus strain MP56 produces high quality antimicrobial substance that might be very useful to control varieties of pathogenic microbial growth.

• Korean Journal of Veterinary Service
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• v.38 no.2
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• pp.65-70
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• 2015

The present study was to investigate in vitro antimicrobial effects of propolis against six different fish bacterial pathogens, Aeromonas hydrophila, Edwardsiella tarda, Vibrio vulnificus, V. parahaemolyticus, A. salmonicida subsp. masoucida, A. salmonicida subsp. salmonicida) using minimum inhibitory concentration (MIC) and minimum bacteriocidal concentration (MBC) tests. In the results, propolis exhibited antimicrobial activity against all bacteria used in the present study, but there was no marked difference in bacterial species except Vibrio species. Collectively, propolis was thought to be an usefulness antimicrobial substance for controlling bacterial diseases in the fish industry.

• International Journal of Human Ecology
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• v.7 no.1
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• pp.145-153
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• 2006

Hwangryeon (Coptidis rhizoma) was extracted by methanol and its antimicrobial activities against food spoilage and 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, and Staphylococcus aureus) and 3 species of fungi (Fusarium solani, Aspergillus flavus, and Penicillium citreonigrum). The Hwangryeon extract showed antimicrobial effect against P. aeruginosa, S. aureus, S. typhimurium, and K. pneumonia. The minimum inhibitory concentration on S. aureus, S. typhimurium, and K. pneumoniae was 300 mg/mL, but on P. aeruginosa it was 200 mg/mL. In the methanol extracts from Hwangryeon, 190 compounds were separated by GC/MS. The extraction yields of phenols, furans, alcohols, acids and esters, ketones, and miscellaneous compounds were 28.10%, 2.67%, 1.79%, 12.89%, and 2.35%, respectively. The phenolic compounds, generally understood to be an antimicrobial active substance, was measured at 28.10%, a relatively remarkable amount.

• 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.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.672-676
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• 2006

The aim of this study is to evaluate the antioxidant, antimicrobial, and antitumor activities of various concentrations of partially purified substance(s) from green tea seed (Camellia sinensis L.). The total polyphenol contents of each fraction (non-adsorption fraction: F-1, fraction eluted with 40% methanol: F-2, and fraction eluted with 100% methanol: F-3) purified by Diaion HP-20 column chromatography were, in the increasing order: F-1 (3.7 mg tannic acid equivalents, TAB/g) < F-3 (23.2 mg TAB/g) < seed extracts (26.2 mg TAB/g) < F-2 (42.7 mg TAB/g). The scavenging activities toward the 1,1-diphenyl-2-picyrylhydrazyl (DPPH) radical were, in decreasing order: F-2 (93.3%) > butylated hydroxytoluene (BHT; 89.8%) > ascorbic acid (89.3%) > leaf extracts (70.3%) > F-3 (15.9%) > seed extracts (15.8%) > F-1 (14.8%) at a 0.1% concentration. In studies on antimicrobial activities, the results indicate that the growth of yeast (Candida albicans KCCM 11282 and Cryptococcus neoformans KCCM 50544) was inhibited more so than that of other fungi (Alternaria alternate KCTC 6005 and Rhizoctonia solani). In addition, it appears that the antitumor activities of the F-1, F-2, and F-3 fractions at a concentration of $50\;{\mu}g/mL$ showed 6, 7, and 23% growth inhibition of the HEC-1B cell line, 14, 11, 82% inhibition of the HEP-2 cell line, and 8, 16, and 81% inhibition of the SK-OV-3 cell line, respectively. Overall these results indicate that the antioxidant activity is greatest in the F-2 fraction, and the antimicrobial and antitumor activities are greatest in the F-3 fraction.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1303-1309
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• 2004

In order to extend shelf-life of the packaged or coated foods, an antibacterial edible film was developed. Antimicrobial activities of 9 bacteriocin-like substance (BLS)­producing strains were evaluated after growing them on defatted soybean meal medium (DSMM). Bacillus subtilis was selected among those, because it showed the biggest inhibition zone against 6 problem bacteria in food. The antimicrobial edible film, containing $0.32\%$ of BLS, was produced from the fermented soybean meal with B. subtilis at the optimum condition of pH 7.0-7.5 and $33^{\circ}C$ for 33 h. The antimicrobial activity of the film was over $50\%$ of the maximum activity after film production with heat treatment at $90^{\circ}C$ and pH adjustment to 9. When the soy protein film with BLS was applied on the agar media containing E. coli, the growth inhibition was much higher than the ordinary soy protein film. These results indicate that the soy protein film with BLS from B. subtilis can be used as a new packaging material to extend the shelf-life of foods.