• Korean Journal of Organic Agriculture
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• v.13 no.2
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• pp.161-173
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• 2005

This study was carried out to clarify the effects of antifungal bacterial strains isolated from the greenhouse soil grown strawberry plants on the growth inhibition of plant pathogen, gray mold (Botrytis cinerea) infected in strawberry plants in Damyang and Jangheung districts. Antagonistic bacterial strains were isolated and investigated into the antagonistic activity against gray mold. Screened ten bacterial strains which strongly inhibited Botrytis cinerea were isolated from the greenhouse grown strawberry plants, and the best antifungal microorganism designated as SB 143 was finally selected. Antifungal bacterial strain SB 143 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. SB 143 showed 59.4% of antifungal activity against Botrytis cinerea. By the bacterialization of culture broth and heated filtrates of culture broth, Bacillus sp. SB 143 showed 93.1% and 32.1% of antagonistic activity against Botrytis cinerea.

• The Korean Journal of Mycology
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• v.6 no.2
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• pp.15-18
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• 1978

The study was performed to investigate the inhibitory action on the growth rate of Candida albicans under the various immunological conditions, Candida albicans was grown in broth media containing 0.1ml. (in total broth volume 4.0ml.) of normal human serum, diabetic patient serum, albumin solution, artifical bulla content and nutrient solution as control subject. The inhibitory action of Candida albicans was indicated by mesurement of transparency rate with use of the spectrophotometer. The results are as follows: 1. Normal human serum shows inhibitory effect on the growth of the candida distinctly. 2. Albumin solution reveals almost similar to that of the effect of normal human serum. 3. Artificial bulla content which obtained by irradiation of ultraviolot ray after application of 1% 8-Methoxy-psolaren cream and the diabetic patient serum shows reduction of inhibitory effect as compared with that of the normal human serum. 4. It is estimated that the titer of negative effect of diabetic patient serum is not related with the variation of immunoglobulin titer in patient serum.

• Korean Journal of Organic Agriculture
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• v.12 no.1
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• pp.101-114
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• 2004

This study was carried out to clarify the effects of antagonistic microorganism, Bacillus sp. JC181 isolated from the greenhouse soil grown cucumber plants on the growth inhibition of plant pathogen, fusarium wilt (Fusarium oxysporum) occurred in cucumber plants in greenhouse. Antagonistic bacterial strains were isolated and were investigated into the antifungal activity of the antagonistic microorganism against fusarium wilt. Screened fourteen bacterial strains which strongly inhibited F. oxysporum were isolated from thc greenhouse soil grown cucumber plants, and the best antagonistic bacterial strain designated as JC181, was finally selected. Antagonistic bacterial strain JC181 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. JC181 showed 58.2% of antifungal activity against the plant pathogen growth of F. oxysporum. By the bacterialization of culture broth and heated filtrates of culture broth, Bacterial strain, Bacillus sp. JC181. showed 91.2% and 260% of antifungal activity against F. oxysporum, respectivrly.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.199-203
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• 1999

To evaluate antidental caries activity of polylysine cell growth and acid production of Streptococcus mutans and lactobacillus acidophilus were microbiologically monitored in anaerobic broth system containing various concentration of polylysine. The pH and heat stability of polylysine having antimicrobial activity were also examined. Two tested microbes were fairly well grown in broth containing polylysine 0.1mg/ml however inhibited at 1 and 2mg/ml of polylysine concentration. Especially lag times of Strep-tococcus mutans and Lactobacillus acidophilus were prolonged to about hour at 1.0 and 2.0 mg/ml of poly-lysine. acid production of Streptococcus mutans and lactobacillus acidophilus was also decreased by poly-lysine. Antimicrobial activity of polylysine was not affected by the change of pH and the heat treat-ment.

• Korean Journal of Microbiology
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• v.17 no.2
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• pp.49-57
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• 1979

Cadimium ion-resistant microorganism was isolated from the sludge of wastewater. The physiological, morphological and other cultural data showed that this strain belonged to Citrobacter freudii. A clearcut distinction of growth among nutrient broth, typtic soy broth and synthetic medium was demonstrated. The resistant cells showed only slight mutagenic action. During the growth of bacterial population in resting state, the organisms reduced the initial level of resistance to cadmium ions when they were not kept in contact with cadmium ions in bacteral multiplication. And cadmium ion-resistant and cadmium ion-sensitive strain were found to show equal, lower or higher sensitivity to other heave metals.

• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.39-44
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• 2000

This study was carried out to develop a new starter culture for the fermented meat products. Nine strains of lactic acid bacteria isolated from kimchi inhibited the growth of Listeria monocytogenes. Among these nine strains, three strains showing antimicrobial activities against Escherichia coil, Staphylococcus aureus and Vibrio paraphaemolyticus were selected for further study. Growth of the strains was inhibited in MRS broth containing 5% of NaCl at $21^{\circ}C$, but not at $32^{\circ}C$. Nitrite depletion ratio of the strains was above 70% after 48h incubation at $21^{\circ}C$, and above 90% after 48h at $32^{\circ}C$ in MRS broth containing $200\mu$g/ml of nitrite, Nitrite concentration of cured meats and ground meats was depleted from 87.6% to 92.3% and from 45.5 to 640.6% by addition of the selected strains for 24h at $32^{\circ}C$, respectively. Three strains were identified as Lactobacillus plantarum(N4) and Lactobacillus lactis ssp. lactis(N-7, an-8).

• Journal of Microbiology and Biotechnology
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• v.1 no.1
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• pp.70-74
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• 1991

The rheological properties of rifamycin B fermentation broth using Nocardia mediterranei were characterized in concomitance with the chemical changes of the fermentation broth. The data were interpreted with various rheological models. As results, it was found that the rheological behaviour at the early growth phases of the culture was the Newtonian fluid, but it was changed to the non-Newtonian fluid (Casson plastic behaviour) at the later phases of the culture. Rheological parameters viz., apparent viscosity ($\mu_a$), yield shear stress ($\tau_o$), and Casson constant ($K_c$) were changed through the fermentation where cell concentrations were changed and mycelia were greatly branched. Those results indicated that cell concentration and cell morphology played important roles to determine the rheological characters.

• Journal of Microbiology and Biotechnology
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• v.20 no.8
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• pp.1240-1242
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• 2010

We attempted to identify the compound responsible for the growth inhibition of Microcystis aeruginosa occurring when a culture broth of Bacillus subtilis C1 was added to the medium. The active compound was purified from B. subtilis C1 culture broth by adsorption chromatography and HPLC, and was identified as a type of glycolipid based on $^1H$ NMR and MS analyses. The purified active compound completely inhibited the growth of M. aeruginosa at a concentration of 10 ${\mu}g/ml$. This is the first report of a glycolipid produced by a Bacillus strain that has potential as an agent for the selective control of bloom-forming M. aeruginosa.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.1030-1034
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• 2009

A fermenting microorganism involved in formation of ortho-dihydroxyisoflavones (ODIs) during aging of doenjang (Korean fermented soybean paste) has been investigated. Microorganisms in ODI-containing doenjang were isolated by cultivating on yeast mold (YM) agar medium containing 0-7% NaCl. ODI formation of the isolated strains was examined by gas chromatography/mass spectrometry (GC/MS) analysis after cultivation in modified YM broth or soybean extract medium. An ODI-producing microbe was identified as Bacillus subtilis HS-1 based on 16S rRNA gene sequence analysis. The strain has produced 8-hydroxydaidzein as a major product during growth in the modified YM broth or soybean extract medium. Therefore, it was concluded that one of the microorganisms involved in the formation of ODIs in doenjang was B. subtilis HS-1.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.04a
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• pp.116-116
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• 1979

In the experiment of cholesterols and steroidal compounds. gas chromatography has been widely used to determine the compounds. Without the facility, we could determine the amount of 17-ketosteroids in the use of t. 1. c technique. In the muicrobial conversion of cholesterol to 17-ketsoteroids, $\alpha,$ $\alpha'-dipyridyl$ which might be a inhibitor of $9\alpha-hydroxylase$ of steroid skeleton was added to microbial culture broth. The inhibitor contaminated due to its solubility in organic solvents and hindered the determination of 17-ketost eroids on t.1. c in all the process of the experiment. we successfully determined the 17-ketosteroids by the use of Ag$^{+}$ band on t. 1. c. plate.e.