• The Korean Journal of Mycology
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• v.24 no.4 s.79
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• pp.310-321
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• 1996

Five strains AF027, AF069, AF2001, AF2011 and SD02 of Pseudomonas cepacia were isolated from soil, and the antifungal cyclic lipopeptides(CLP) i.e, CLP027A, CLP069A, Cepacidine A, CLP2011A and CLP02A were produced from each strains, respectively. Nitrogen and carbon sources in media were proved to be important factors for the production of CLP and among them, polypeptone-S, glucose and fructose were the most effective. It appeared that compounds CLP027A and CLP069A were identical with Cepacidine A and Xylocandine A, respectively. contain aspartic acid as amino acid component, are differentiated from Xylocandine A containing asparagine. Although molecular weight, amino acid composition and UV spectrum of CLP2011A and CLP02A are same with those of Cepacidine A, it is postulated that these compounds are not identical with Cepacidine A when the antifungal spectra and antifungal activity were compared to those of Cepacidine A.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.668-680
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• 2020

Bacillus velezensis is an important plant growth-promoting rhizobacterium with immense potential in agriculture development. In the present study, Bacillus velezensis Lle-9 was isolated from the bulbs of Lilium leucanthum. The isolated strain showed antifungal activities against plant pathogens like Botryosphaeria dothidea, Fusarium oxysporum, Botrytis cinerea and Fusarium fujikuroi. The highest percentage of growth inhibition i.e., 68.56±2.35% was observed against Fusarium oxysporum followed by 63.12 ± 2.83%, 61.67 ± 3.39% and 55.82 ± 2.76% against Botrytis cinerea, Botryosphaeria dothidea, and Fusarium fujikuroi, respectively. The ethyl acetate fraction revealed a number of bioactive compounds and several were identified as antimicrobial agents such as diketopiperazines, cyclo-peptides, linear peptides, latrunculin A, 5α-hydroxy-6-ketocholesterol, (R)-S-lactoylglutathione, triamterene, rubiadin, moxifloxacin, 9-hydroxy-5Z,7E,11Z,14Z-eicosatetraenoic acid, D-erythro-C18-Sphingosine, citrinin, and 2-arachidonoyllysophosphatidylcholine. The presence of these antimicrobial compounds in the bacterial culture might have contributed to the antifungal activities of the isolated B. velezensis Lle-9. The strain showed plant growth-promoting traits such as production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, and nitrogen fixation and phosphate solubilization. IAA production was accelerated with application of exogenous tryptophan concentrations in the medium. Further, the lily plants upon inoculation with Lle-9 exhibited improved vegetative growth, more flowering shoots and longer roots than control plants under greenhouse condition. The isolated B. velezensis strain Lle-9 possessed broad-spectrum antifungal activities and multiple plant growth-promoting traits and thus may play an important role in promoting sustainable agriculture. This strain could be developed and applied in field experiments in order to promote plant growth and control disease pathogens.

• Archives of Pharmacal Research
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• v.15 no.3
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• pp.263-268
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• 1992

In order to evaluate the antimicrobial effect of 2, 3-disubstitued-1, 4-naphtoquinone derivatives we newly synthesized several 2-bromo-3-(substituted)-1, 4 naphthoquninones. Amination reaction of 2, 3-dihalo-1, 4 naphthoquinones with aryl and aliphatic amines in ethanol gave 2-halo-3-(N-alkyl or N-aryl)1, 4-naphtoquinone derivatives (1a, b-10a, b) i 60% 90%) yield. These derivatives subjected to antibacterial and antifungal activities. in vitro, against Bacilllus subtilis ATCC 6633 Candida albicans 10231 and local, Psudomonas aeruginosa NCTC10490, Staphylococcus aureus ATCC 6538p. Escherichia coli NIHJ Aspergillus niger KCTC 1231, Tricophyton mentagrophytes KCTC 6085. Among these derivatives 1b, 6b and 7a showed the potent antibacterial activities 1b, 8b and 9b have derivatives, 1b, 6b and 7a showed the potent antibacterial activities. 1b, 8b and 9b have the antifungal activities. 1b is most effective in preventing the growth of Bacillus subtilis and Psudomonas aeruginosa. Candida albicans. Aspergillus niger. Tricophyton mentagrophytes. The several of these compounds demonstrated a broad spectrum of activities in vitro.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.415-419
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• 2003

One strain was isolated from wilted chestnut tree and identified as Helicosporium nizamabadense. Also, the strain was evaluated for biocontrol potentials against phytopathogens. Autoclaved fraction of the isolate also showed complete growth inhibition of the turfgrass large patch pathogen, Rhizoctonia. solani AG2-2 and plant pathogen, Botrytis cinerea. Culture extracts of Helicosporium nizamabadense were purified by Thin Layer Chromatography. The several fractions were analyzed by GC-MS, and NMR etc. Antifungal activities were presumably showed more than 5 fractions against the pathogens. Among them, the most effective antifungal fraction was identified as 2-Methylresocinol using GC-MS, and NMR. These results suggest that the 2-Methylresocinol may be useful for biochemicals.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.150-153
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• 2003

Methanol extract obtained from Lindera erythocarpa leaves was successively fractionated with n-hexane, ethylacetate, n-butanol, and $H_2O$. From ethylacetate fraction, an active fraction was isolated through repeated silica gel column chromatography and recrystallization, and was identified as a stereoisomer complex of methyllucidone by MS and MMR analyses. The complex showed 85% antifungal activity at 50 {\mu}g/ml$ against the disease wheat leaf rust.

• The Plant Pathology Journal
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• v.32 no.3
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• pp.209-215
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• 2016

In this study, the treatment of pistachio nuts by Bacillus subtilis UTBSP1, a promising isolate to degrade aflatoxin B1 (AFB1), caused to reduce the growth of Aspergillus flavus R5 and AFB1 content on pistachio nuts. Fluorescence probes revealed that the cell free supernatant fluid from UTBSP1 affects spore viability considerably. Using high-performance liquid chromatographic (HPLC) method, 10 fractions were separated and collected from methanol extract of cell free supernatant fluid. Two fractions showed inhibition zones against A. flavus. Mass spectrometric analysis of the both antifungal fractions revealed a high similarity between these anti-A. flavus compounds and cyclic-lipopeptides of surfactin, and fengycin families. Coproduction of surfactin and fengycin acted in a synergistic manner and consequently caused a strong antifungal activity against A. flavus R5. There was a positive significant correlation between the reduction of A. flavus growth and the reduction of AFB1 contamination on pistachio nut by UTBSP1. The results indicated that fengycin and surfactin-producing B. subtilis UTBSP1 can potentially reduce A. flavus growth and AFB1 content in pistachio nut.

• Journal of Applied Biological Chemistry
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• v.60 no.3
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• pp.265-269
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• 2017

Environment-friendly, commercially-available agricultural products were investigated for antimicrobial activity against Sclerotinia sclerotiorum, as a pathogen of sclerotium disease. Then ${\beta}$-thujaplicin from Chamaecyparis obtuse was investigated for antifungal activity against six kinds of pathogenic fungi. It showed a statistically significant (p <0.001) growth inhibition effect on Sclerotinia sclerotiorum as a pathogen of sclerotium disease, Rhizoctonia solani AG-4 as a pathogen of damping off, Phytophthora capsici as a pathogen of phytophthora blight, and Colletotrichum coccodes as a pathogen of anthracnose at a concentration of 50 ppm and on Stemphylium solani as a pathogen of spotting disease and Alternaria alternata as a pathogen of black mold at a concentration of 100 ppm. In conclusion, these results indicate that it may be possible to develop environment-friendly agricultural products using ${\beta}$-thujaplicin compounds.

• Mycobiology
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• v.35 no.3
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• pp.150-153
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• 2007

New $N_2O_2$ donor type Schiff base has been designed and synthesized by condensing acetoacetanilido-4-aminoantipyrine with 2-aminobenzoic acid in ethanol. Solid metal complexes of the Schiff base with Cu(II), Ni(II), Co(II), Mn(II), Zn(II), VO(IV), Hg(II) and Cd(II) metal ions were synthesized and characterized by elemental analyses, magnetic susceptibility, molar conduction, fast atom bombardment (FAB) mass, IR, UV-Vis, and $^1H$ NMR spectral studies. The data show that the complexes have the composition of ML type. The UV-Vis. and magnetic susceptibility data of the complexes suggest a square-planar geometry around the central metal ion except VO(IV) complex which has square-pyramidal geometry. The in vitro antifungal activities of the compounds were tested against fungi such as Aspergillus niger, Aspergillus flavus, Rhizopus stolonifer, Candida albicans, Rhizoctonia bataicola and Trichoderma harizanum. All the metal complexes showed stronger antifungal activities than the free ligand. The minimum inhibitory concentrations (MIC) of the metal complexes were found in the range of $10{\sim}31{\mu}g/ml$.

• Journal of Apiculture
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• v.34 no.2
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• pp.125-129
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• 2019

Honey bees are important pollinators in agriculture, but are threatened by the pathogen Ascosphaera apis, which causes chalkbrood. Despite attempts to control this fungus using synthetic fungicides, none of them have been proven to be completely effective. Among 640 natural compounds that we tested, 4-hydroxyderricin (MIC=3.125, 6.25 mg/L after 24 h and 48 h growth, respectively) exhibited the strongest anti- Ascosphaera apis activity, followed by acetylshikonin (MIC=12.5 mg/L for 24 h and 48 h growth). 4-Hydroxyderricin showed selective growth inhibition of Ascosphaera apis and Rhizopus oryzae among tested fungus strains. Treatment 4-hydroxyderricin with miconazole revealed a synergistic effect (FICI=0.65±0.13 at 48 h incubation). These findings suggest that 4-hydroxyderricin, which has antifungal activity against Ascosphaera apis but few other fungal species, can effectively control infectious fungal diseases. Combined treatment of bees with 4-hydroxyderricin and miconazole could reduce cytotoxicity and improve the cost effectiveness of treatment.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.88-101
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• 2008

The aim of this study was to attempt the efficacy of antifungal activity of the wood extracts against Botrytis grey mold. Wood chip derived from Quercus mongolica was obtain from steam explosion process and extracted by hot water and methanol and ethanol. The conidial germination was maximum growth with the application temperature for 20 and $25^{\circ}C$. In pH test, we observed the maximum growth in pH 5.0 and 7.0. Antifungal activity was the best in the hot water extractives against Botrytis cinerea. The separation of the antifungal substances was performed using a silica-gel column (n-hexane : chloroform : ethyl acetate : formic acid = 12 : 17 : 8 : 0.2, v/v/v/v), TLC and UV-Spectrophotometer, and isolated 6 fraction group. The result of antifungal activity in 6 fraction group, fraction group I and fraction group II were the highest antifungal activity against grey mold with the present study. Three peaks in fraction group I and II were detected by HPLC and this compounds were suppose to effective of antifungal activity.