• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.205.2-205
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• 1994

• Applied Biological Chemistry
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• v.41 no.3
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• pp.208-212
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• 1998

In order to develop an effective antifungal antibiotics, over 700 isolates of bacteria, mold and actinomytes were screened from soil, and LAM 97-44 were selected as a strain producing the strong antifungal antibiotics against Candida albicans. Morphological, cultural and physiological characteristics of LAM 97-44 were investigated for the indentification. The cell size of LAM 97-44 was $2{\sim}3{\times}1{\sim}1.5\;{\mu}m$, and the shape of spore was of ellipsoidal. As a carbon source, LAM 97-44 utilized fructose, glucose, glycerol, maltose and raffinose but did not utilize arabinose, cellulose and xylose. The fatty acids of the cells included various iso-type and anteiso-type. Conclusively, the strain LAM 97-44 was proved to be Bacillus subtilis.

• KSBB Journal
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• v.18 no.6
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• pp.490-494
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• 2003

For the production of antifungal compound, strain B-1 was used as a strong producing strain among bacteria isolated from various soil samples. The optimum medium for the production of antifungal compound was PDB (potato starch 0.4%, dextrose 2％, pH5.1). The optimum conditions for the production of antifungal compound didn't affect on the carbon and nitrogen sources. The produced compound showed broad antimicrobial activity to the tested strains such as five fungi and four bacteria. The optimum pH and temperature of the production antifungal compound were pH 5.0 and 28$^{\circ}C$, respectively. Ether extrct (1$\mu\textrm{g}$/${\mu}\ell$) of culture broth was confirmed inhibitory zone by the thin layer chromatography and plate assay. The antimicrobial compound was unstabled after heat (121$^{\circ}C$) trsatment. Strain B-1 was mass cultured in a 5-liter tormentor, containing 3 liters of PDB medium at 28$^{\circ}C$, pH 5.0, 120 (pm with aeration (1L/min).

• Journal of Life Science
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• v.14 no.5
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• pp.859-862
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• 2004

This report investigates antifungal activity and effects of growth promotion by biosurfactant produced from Bacillus sp. LP03 and TBM40-3 against fungus causing plants disease (Glay Mold-Botrytis cinerea). Antifugal activity against B. cinerea infeeted to leek (Allium tuberosum Rottler) exhibited better than antifungal agent farming drug (smilex, Dong bang agro., Seoul, Korea.) through the field test. After infected by plant's disease, the leaves growth and number are maintained under presenting biosurfactant produced strains. Especially, one of the strains, named Bacillus sp. LP03 showed strong antifungal activity on field studies.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.18-22
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• 2007

The optimum production condition for the antibiotic from Bacillus thuringiensis BK4 was determined, and the suppression rate of Fusarium-wilt by the butanol-extracted antibiotic was verified by employing tomatoes in vitro and in vivo pot tests. Cell growth and antifungal activity were the best when 0.5% xylose and 0.2% peptone No.3 were given as carbon and nitrogen sources, respectively, in the presence of 5mM $CaCl_2$. The partially purified antibiotic successfully prevented Fusarium oxysporum pathogen in pot experiments. When the pots were treated with both live cells and the partially purified antibiotic, an additive-effect was seen in the suppression of Fusarium-wilt, but synergistic effect was not detected. The antibiotic, denoted BK4, purified by Sephadex LH-20 column chromatography was eluted with a single peak at a retention time of 38 min. on prep-HPLC; Minimum inhibition concentration of the homogenous antibiotic was determined to be 50${\mu}$g/ml.

• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.186-193
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• 2001

A powerful antagonistic bacterium against Phytophthora capsici causing phytophthora blight of red pepper was isolated from the cultivated soil in Kyongju Korea, The bilogical control mechanisms of the isolated strain were caused by strong antifungal antibiotic, siderophore and cellulase. The strain was identified as Chryseomonas luteola by the cultural morphological and physiological characteristics. The opti- mal culture medium for the antibiotic production was determined as follows : 0.15%D(+) cellobiose, 0.55% $NH_4$CI, 0.01% KCI 0.7% $K_2$$HPO_4$ 0.2% $KH_2$PO$_4$ and 0.5% sodium citrate at pH 7.0 The optimal incubation time was 84 hours at $30^{\circ}C$ In pot bioassay, the treatment of C luteola 5042 protected red pepper plant against the blight of Phytophthora capsici.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.69-73
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• 2003

A novel antifungal antibiotic for azole-resistant Candida albicans was purified from the culture broth of Bacillus subtilis LAM 97-44 by butanol extraction, Diaion HP-20 and Dowex-50 adsorption chromatography, silica gel flash chromatography followed by HPLC and designated LAM-44A. LAM-44A was stable for 60 min at $100^{\circ}C$, and pH range from 2 to 10. MIC values were observed at $0.5-3.5\;{\mu}g/ml$ against various Candida albicans strains. The antibiotic showed no cytotoxicity for S180, MKN-45, P388, HeLa and 373 at the concentration of 1 mg/ml. LAM-f4A was colorless powder soluble in water, methanol, ethanol, butanol and negative to ninhydrin reaction. The antibiotic had maximum absorption at 273 nm in methanol, and melting point was $202^{\circ}C$. The molecular weight and formula were determined to be 282 and $C_{14}H_{34}O_5$ by $^1H-NMR,\;^{13}C-NMR$, IR spectrum and elemental analysis.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.30-35
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• 2008

purpose of the study was to synthesize new series of 5-cyano substituted pyrimidine analogues with different substitutions at N1 and 6 positions and to evaluate them for antibacterial and antifungal activities. The desired compounds were synthesized by tertiary condensation of ethylcyanoacetate, substituted thioureas and suitable aldehyde in presence of potassium carbonate using MORE technique. The antibacterial and antifungal activities were evaluated by cup plate method in the concentration of 25 mg. The zone of inhibition was measured in mm. All the compounds have shown significant antibacterial and antifungal activities. The maximum activity was shown by P1 and P5 against S.aureus and E.coli respectively, while P6 has shown significant activity against all types of microorganisms. The compound P8 has been found to be significantly effective against C. albicans. Norfloxacin and griseofulvin were used as standards to compare the activites of synthesized compounds. It is concluded that analogues containing p-hydroxy, p-methoxy substituted phenyl moiety at 6 position have been found to be more potent against gram-positive microorganisms, while analogues lacking these substituents on phenyl moiety possessed gram-negative activity. The compounds having p-dimethylamino substituent on phenyl moiety at 6 positions have shown moderate activity. Further, only fluorine containing analogue at N1 position was found to possess appreciable antifungal activity. This suggests that electron donating substituent on aryl moiety as well as electron withdrawing substituent at N1 plays important role in determining potency of the compounds.

• Journal of Life Science
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• v.13 no.2
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• pp.223-229
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• 2003

A study of the anti-fungal properties in Korean radish was conducted using a variety of purification procedures such as Extrelut column, RP(Reverse Phase) Cl8 Column Chromatography, HPLC etc. to separate anti-fungal substances from Korean radish juices to test them against a common gray mold called Botrytis cenerea. Dialysis tube operation showed that these substances were presumably thermostable compounds with low molecular mass (less than 3.5 kDa). Differences of anti-fungal activities depending upon types of radishes used did not show any noticeable variation. The antifungals were presumably composed of more than 5 compounds. Among these, the most anti-fungal fraction was analyzed by HPLC in which one peak was obtained. Disease-affected plants were inoculated with 10mg of Extrelut fraction and results showed similar anti-fungal activity to pesticides suggesting possible usage of these substances as environmentally friendly antibiotics.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2005.12a
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• pp.114-114
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• 2005