• Mycobiology
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• v.30 no.2
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• pp.93-95
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• 2002

The antifungal activities of propolis on Cryptococcus neoformans and Candida albicans were evaluated. In microbroth culture assay, the MIC(minimum inhibitory concentration) of propolis for C. neoformans and C. albicans were 2 and 16 mg/ml, respectively. In propolis-included solid medium assay, the MIC of propolis for C. neoformans and C. albicans were 4 and 16 mg/ml, respectively. Propolis showed fungicidal activity against C. neoformans, whereas propolis possesed fungistatic activity against C. albicans. The MFC(minimum fungicidal concentration) for C. neoformans was 8 mg/ml. Cell morphology of C. neoformans was affected by treatment of propolis. In scanning electron microscope, the appearance of cell rupture was observed.

• Natural Product Sciences
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• v.22 no.1
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• pp.35-40
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• 2016

The first study on chemical constituents and biological activities of Clausena lansium (Lour.) Skeels (Rutaceae) growing in Vietnam has been done. Phytochemical investigation of n-hexane extract led to the isolation of five compounds: dihydroindicolactone (1), 8-geranyloxy psoralen (2), imperatorin (3), heraclenol (4) and indicolactone (5), in which this is the first report on the presence of dihydroindicolactone (1). Their structures were elucidated based on LC/MS/NMR hyphenated techniques as well as comparison with those of literature data. The n-hexane extract and its subfractions, ethanol 95% extract and several isolated compounds were evaluated for antifungal activity.

• Mycobiology
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• v.45 no.3
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• pp.192-198
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• 2017

The green peach aphid (Myzus persicae), a plant pest, and gray mold disease, caused by Botrytis cinerea, affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae. Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.338-344
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• 1998

New type of chitosan derivatives, chitosan-g-MAP, were synthesized by graft copolymerization of mono (2-methacryloyl oxyethyl) acid phosphate (MAP) into chitosan, in order to solubilize chitosan in water. Ceric ammonium nitrate was used as an initiator for graft copolymerization. The optimal conditions for graft copolymerization were determined on the basis of reaction temperature, time, and the concentration of initiator and monomer. The reaction conditions for the highest percentage of grafting were as follows: an initiator concentration, 3.5${\times}$10$\^$-3/ M; monomer concentration, 0.19 M; and reaction temperature, 40$^{\circ}C$ The reaction rate reached the maximum value after 4 hrs of reaction. Antifungal activity was tested against Candida albicans, Trichophyton rubrum and Trichophyton violaceum by using chitosan-g-MAP and two other chitosan samples which have degree of deacetylation of 70% (DA-7) and 90% (DA-90). Their antifungal activities were investigated in weak acidic range. Maximum antifungal activity of them was observed at pH 5.75. Chitosan-g-MAP inhibited thoroughly the growth of Candida albicans and Trichophyton violaceum. Howerver, DA-70 and DA-90 showed higher antifungal activities on Trichophyton rubrum than that of chitosan-g-MAP.

• The Plant Pathology Journal
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• v.15 no.5
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• pp.280-286
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• 1999

Lichen-forming (LFF) or lichenicolous fungi (LCF) were isolated from the lichens collected at‘Backwoon’mountain area,‘Chiri’mountain area and‘Sorok’island in the southern regions of Korea and were screened for antagonistic efficacy against several phyto-pathogenic fungi. Symbiotic algae-free LFF and LCF were isolated by the following methods: I) discharged spores (ascospores), II) macerated thallus suspension and III) direct use of thallus fragments. Among 58 isolates obtained from 34 lichens, 8 isolates showed antifungal activity against Rhizoctonia solani. Antifungal activities of the strongest antagonistic isolate (LB9810) originated from the thallus of Parmelia quercina lichen were evaluated against 15 phyto-pathogenic fungi. When crude methanol extract of mycelia of the LB8910 isolate was employed at the rate of 0.5% (v/w), fungal growth of Magnaporthe grisea and Rhizoctonia solani was severly and Rhizoctonia solani was severly inhibited as much as approximately 60% compared to control. Growth of various food-borne same extract. The extract was successively partitioned with n-hexane, ethyl acetate and n-butanol. n-Hexane fraction displayed the strongest antifungal activities against R. solani. The LB9810 isolate was finally identified as Fusarium equiseti (Corda) Sacc., which has not been reported as LFF or LCF yet. Therefore, it is very likely that F. equiseti isolated it the study was originated from the contaminants associated with thallus fragments rather than from LFF or LCF.

• Journal of the Korean Wood Science and Technology
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• v.30 no.1
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• pp.48-55
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• 2002

The essential oils were extracted from the needles of several softwood tree species, Pinus densiflora, Pinus koraiensis, Chamaecyparis obtusa and Chamaecyparis pisifera to investigate their biological activities. The antifungal activity by hyphal growth inhibition method was determined by three wood rot fungi, one mouldous fungi, and three tree pathogenic fungi and the antibacterial activity by paper disc method and turbidiometric method by three gram positive bacteria and one gram negative bacteria, Escherichia coli, were also tested. Antifungal activity was the best in the essential oil from C. obtusa, and the following was resulted in order of P. densiflora and P. koraiensis. The essential oil from P. densiflora showed higher antifungal activity against wood rot fungi than that from P. koraiensis while the result was contrary against tree pathogenic fungi. However, the antibacterial activity was the best in the essential oil from P. densiflora, and the following was in order of C. obtusa and P. koraiensis. From these results, the variation of biological activity seemed to be due to the chemical composition of essential oils.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.59.3-60
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• 2002

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.70-75
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• 2013

Seven medicinal plant extracts were tested for antifungal activities against six species of the major turfgrass pathogenic fungi (Colletotrichum graminicola, Pythium spp., Rhizoctonia cerealis, Rhizoctonia solani AG1-1, Rhizoctonia solani AG2-2, and Sclerotinia homoeocarpa) using paper disk diffusion method. Three medicinal plant extracts, including Pinus densiflora showed antifungal activities. In suppression of mycelium growth test, on medium adding P. densiflora extract showed that inhibition rate of mycelium growth were above 80% in 10 mg/10 ml concentration of the extract. The inhibition rate of Pythium spp. was 100% and C. graminicola was 84.3% in 10 mg/10 ml concentrations of P. densiflora extract, respectively. In particularly, the inhibition rate of Pythium spp. was 89.5% in 2 mg/10 ml concentrations of P. densiflora extract. As a result, P. densiflora extract showed high antifungal activity to Pythium spp. and C. graminicola of the turfgrass pathogen in in vitro test.

• 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.

• Mycobiology
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• v.31 no.2
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• pp.95-98
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• 2003

Aantifungal agents were tested against 30 clinical isolates of Cryptococcus neoformans var. neoformans using the NCCLS method(M27-A2). Posaconazole, itraconazole and amphotericin B had lower MIC than the remaining four antifungal agents. The MIC result for posaconazole was over 220-fold lower active than fluconazole. Fluconazole MICs for most isolates fell within the dose-dependant range. The overall MIC ranges and $MIC_{50}s$ were amphotericin B(0.03-0.25; 0.25), fluconazole(0.5-64; 16), itraconazole(0.015-1; 0.125), terbinafine(0.06->2; 1), caspofungin(8-32; 32), voriconazole(0.015-0.5; 0.25), and posaconazole(0.015-0.25; 0.06 ${\mu}g/ml$), respectively. In conclusion, the $MIC_{50}s$ of these drugs did not exhibit any sign of an upward shift with the exception of fluconazole and tendency cross-resistance between the seven drugs was not observed. We conclude that in vitro resistance to antifungal agents has not significantly changed despite the recent wide-spread use of triazoles for long-term treatment of Cryptococcal meningitis.