• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.340-349
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• 2009

A CJ9 bacterial strain, which showed antifungal and antibacterial activities, was isolated from meju and identified as Bacillus polyfermenticus based on Gram staining, biochemical properties, as well as its 16S rRNA sequence. B. polyfermenticus CJ9 showed the antimicrobial activity against the various pathogenic molds, yeasts, and bacteria. The antibacterial activity was stable in the pH 5.0~9.0, but the activity was lost at $37^{\circ}C$ for 24 hr. The antifungal activity was stable in the pH range of 3.0~9.0 and reduced at $121^{\circ}C$ for 15 min, but antifungal activity was not completely destroyed. The antibacterial activity was completely inactivated by proteinase K, protease, trypsin, and $\alpha$-chymotrypsin. The antifungal activity was also completely inactivated by protease and $\alpha$-chymotrypsin, and reduced its activity by proteinase which indicated that the antifungal and antibacterial compounds have proteineous nature. The apparent molecular mass of the partially purified antifungal compound, as indicated by using the direct detection method in Tricine-SDS-PAGE, was approximately 1.4 kDa. The molecular mass of the antibacterial compound could not be determined because of its heat-liable characteristic.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.339-346
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• 2007

The MJP1 bacterial strain, which possesses antifungal activity, was isolated from meju and identified as Bacillus subtilis based on its morphological and biochemical properties, as well as its 16S rRNA sequence. Antimicrobial activity was found against various species of Gram-positive bacteria, yeasts, and molds, including food-spoilage microorganisms. The antifungal activity was found to be stable after heat and proteolytic enzyme treatment, and in the pH range of $6.0{\sim}10.0$. The antibacterial activity was stable in the pH range of $6.0{\sim}10.0$, but about 50% of the activity was lost after 24 hr at $30^{\circ}C$. The antibacterial compound was also inactivated by proteolytic enzyme treatment, indicating its proteinaceous nature. The apparent molecular masses of the partially purified antifungal and antibacterial compounds, as indicated by using the direct detection method in Tricine-SDS-PAGE, were approximately 2.4 kDa and 4.5 kDa, respectively. These studies suggest that B. subtilis MJP1 produces two bacteriocin-like substances with antifungal and antibacterial activities.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.59-65
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• 2009

The antimicrobial activity-possessing materials were screened in the cell free supernatant (CFS) of fourteen lactic acid-fermenting strains isolated from pig's intestine. Each cell free supernatant of cultured strains was treated with various proteinases, heat, and/or alkali (NaOH). The antimicrobial activities were remained even after the enzyme and heat treatment but disappeared after neutralization with 1M NaOH, implying that the materials would be organic acids rather than proteins. Further purification of CFS through solid phase extraction using Sep-pak $C_{18}$ Cartridges and high performance anion exchange chromatography using Bio-LC system revealed that four organic acids, such as oxalic acid, citric acid, lactic acid, and acetic acid, were the main materials for the activity. Lactic acid was the highest amount in all organic acids, ranging from 54% to 77%. This strongly implies that the lactic acid would be the primary material for the antimicrobial activity in all tested strains.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.2
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• pp.112-120
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• 2006

For the conversion of food waste into a good recycling material such as animal feed without antibiotics, thirteen lactic acid bacteria, which can be used as good probiotics for animal feed, were isolated from the intestine and feces in pigs. All isolates showed strong tolerance to high salt (4% of NaCl), acid(pH4.0), and bile juice (0.8% of oxgall). The growth rate was best at $37^{\circ}C$ in all strains. Among the isolates, Lactobacillus plantarum CJY-22, L. brevis CJY-42, L. arizonensis CJY-3, and Pediococcus sp. CJY-41 showed higher and broader spectrum of antimicrobial activities against six different pathogens such as Salmonella, typhimurium. L. plantarum CJY-22 has also grown well at $25^{\circ}C$, making this strain as an appropriate candidate for the fermentation of food waste at room temperature, thus conducting the fermentation process cost-effectively.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.84-92
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• 2010

Antibacterial compound from Bacillus subtilis MJP1 was purified using C18 Sep-Pak cartridge, ion exchange chromatography, and gel filtration chromatography. The purified antibacterial compound showed antibacterial activity against Listeria monocytogenes, Bacillus subtilis, Staphylococcus aureus subsp. aureus, and Enterococcus faecalis. The purified antibacterial compound was found to be stable at $100^{\circ}C$ for 5 min and in the pH range of 3.0~9.0, but it was unstable at pH 10.0. It was inactivated by proteinase K and pronase E, and heat treatment at $121^{\circ}C$ for 15 min, but it was stable with lipase and $\alpha$-amylase treatment, which indicated its proteineous nature. Ultra performance liquid chromatography and electrospray ionization tandem mass spectrometry analysis were used to identify the purified antibacterial compound and confirmed the existence of two peptides (3356.54 Da, 3400.5244 Da).

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.903-911
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• 2011

In this study, Bacillus polyfermenticus CJ6 harboring antibacterial activity was isolated from meju. The antibacterial activity of Bacillus polyfermenticus CJ6 was stable in the pH range of 3.0~9.0, but it disappeared after culture at $70^{\circ}C$ for 24 hr. Antibacterial activity was inactivated by proteinase K, protease, and ${\alpha}$-chymotrypsin, indicating its proteinaceous nature. The growth inhibitory effects of B. polyfermenticus CJ6 culture on food-borne pathogens such as Staphylococcus aureus, Salmonella Typhi, Listeria monocytogenes, and Escherichia coli O157:H7 were examined in this study. Approximately 6~6.2 log CFU/mL of each pathogen was co-cultured with B. polyfermenticus CJ6 in a 50 mL culture volume for 24 hr. Growth of S. aureus and L. monocytogenes was completely inhibited after 3 hr of incubation. Growth of S. Typhi and E. coli O157:H7 was also completely inhibited after 6 hr of incubation. The antibacterial compounds from B. polyfermenticus CJ6 were purified by solid phase extraction (C18 Sep-pak cartridge), recycling preparative HPLC, and analytical HPLC. Ultra-high performance liquid chromatography and electrospray ionization tandem mass spectrometry analysis were used to identify the purified antibacterial compounds, which were confirmed to be five peptides (757.4153 Da, 750.3444 Da, 1024.5282 Da, 1123.6083 Da, and 1617.8170 Da).

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.420-424
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• 2002

The purpose of this study is to investigate anticariotic activity of the ethyl acetate soluble extract of Sophora flavescens Ait. for the prevention of dental caries and glucosyltransferase activity caused by Streptococcus mutans. The fraction 5-4-3 showed strong growth inhibition activity against Streptococcus mutans (MIC, 3.13 $\mu\textrm{g}$/ml). The glucosyltransferase activity of the active fraction 5-4-3 inhibited the formation of glucan and showed 77% of the antiproliferative effect at 100 $\mu\textrm{g}$/ml (P<0.05). Two flavanones, (2S)-2'-methoxy kurarinone (1) and (+)-kurarinone (2), were isolated from the active fraction 5-4-3 of the ethyl acetate soluble extract of S. flavescens Ait. Their structures were elucidated using spectroscopic methods.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.44-51
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• 2013

We prepared culture extracts of 174 Corallococcus and 207 Myxococcus strains isolated in Korea, and compared their antimicrobial activity against Candida albicans, Pseudomonas aeruginosa, and Staphylococcus aureus. The percentage of strains showing antifungal activity was lower in Corallococcus (7.5% [13 of the 174 strains]) than in Myxococcus (51.7% [107 of the 207 strains]). However, the percentage of strains exhibiting antibacterial activity was higher in Corallococcus (12.1% [21 strains]) than in Myxococcus (1% [2 strains]). The culture extracts of 6 Corallococcus strains inhibited both P. aeruginosa and S. aureus and displayed similar high-performance liquid chromatography chromatograms, although the shapes of their fruiting bodies were dissimilar. The rate of production of antibacterial substances was the highest when the strains were cultured in CYS medium for more than 6 days.

• The Korean Journal of Food And Nutrition
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• v.13 no.6
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• pp.539-546
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• 2000

The purpose of this study is to investigate antibacterial activities of Sophora flavescens Ait. extracts for the prevention of dental caries caused by Streptococcus mutans. The fraction 5-4-3 of the ethyl acetate soluble extract of Sophora flavescens Ait. Showed strong growth inhibition activity against Streptococcus mutans (MIC, 3.13 ${\mu}$g/ml). The glucosyltransferase activity inhibited the formation of glucan by the fraction 5-4-3 and showed 77% of the antiproliferative effect at 100 ${\mu}$g/ml. This showed a significant activity (p<0.05). These results suggest that the fraction 5-4-3 of the ethyl acetate soluble extract of Sophora flavescens Ait. may be a valuable material as the prevention of dental caries.

• The Korean Journal of Mycology
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• v.24 no.1 s.76
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• pp.25-37
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• 1996

Antifungal and antibacterial activities of 108 extracts from 36 species of mushrooms in Korea were screened. The powder of fruiting body of each mushroom was extracted with petroleum ether, 80% ethanol and distilled water subsequently. Among these, five extracts including the ethanol extract of Agaricus subrutilescens, seven extracts including the water extract of Amanita virosa, nine extracts including the water extract of Amanita pantherina and twenty five extracts including the water extract of Lycoperdon perlatum showed antibiotic activities against yeasts, fungi, Gram-negative bacteria and Gram-positive bacteria, respectively.