• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.811-816
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• 2000

An antagonistic bacterium PM-1 which strongly inhyibits the growth of Pyricularia oryzae was isolated and identified as paenibacillus macerans. The antifungal substances of the strain PM-1 showed the broad antifungal spectra against P.oryzae races. Relating to the localization test, it was found that the antifungal substances existed not only in the cytoplasm but also in the culture supernatant, and importantly the antifungal activity of the latter was stronger than that of the former. The extracellular antifungal substances were extremely heat-stable up to $121^{\circ}C$ for 15 min. The substances were optimally produced at $20^{\circ}C$ and pH 10.0 in a potato dextrose broth. The culture filtrate of the strain PM-1 caused a partial swelling of the mycelia of P.oryzae, and it prevents the normal growth of the fungus as well. This result suggested that the antifungal substances secreted by the strain PM-1 potentially inhibited the germination of P.oryzae.

• Journal of Pharmacopuncture
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• v.19 no.1
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• pp.45-50
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• 2016

Objectives: The purpose of this study was to investigate the antifungal effect of bee venom (BV) and sweet bee venom (SBV) against Candida albicans (C. albicans) clinical isolates. Methods: In this study, BV and SBV were examined for antifungal activities against the Korean Collection for Type Cultures (KCTC) strain and 10 clinical isolates of C. albicans. The disk diffusion method was used to measure the antifungal activity and minimum inhibitory concentration (MIC) assays were performed by using a broth microdilution method. Also, a killing curve assay was conducted to investigate the kinetics of the anti-fungal action. Results: BV and SBV showed antifungal activity against 10 clinical isolates of C. albicans that were cultured from blood and the vagina by using disk diffusion method. The MIC values obtained for clinical isolates by using the broth microdilution method varied from $62.5{\mu}g/mL$ to $125{\mu}g/mL$ for BV and from $15.63{\mu}g/mL$ to $62.5{\mu}g/mL$ for SBV. In the killing-curve assay, SBV behaved as amphotericin B, which was used as positive control, did. The antifungal efficacy of SBV was much higher than that of BV. Conclusion: BV and SBV showed antifungal activity against C. albicans clinical strains that were isolated from blood and the vagina. Especially, SBV might be a candidate for a new antifungal agent against C. albicans clinical isolates.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.335-337
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• 1997

In this study, we show a convenient MTT assay for detect the susceptibility of yeast-like form of Trichosporon beigelii against antifungal agents. This assay was developed based on mitocondrial respiration by determining reduction of 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) to formazan. Cells of T beigelii are seeded into 96-well microtiter plates, and antifungal agents, amphotericin B, magainin and CA-ME hybrid peptide were added with various concentrations. After 24 hr incubation, MTT was added, then incubations were continued for 4 hr. Formazan formation was quantified photometrically after extraction of the formazan with acid sodium dodesyl sulfate (SDS). From this assay, we could obtained MICs of antifungal agents against T. beigelii. The presented method can easily be used as an effective methods to assess the antiftingal action of various agents on yeasts with minimal amounts of antifungal agents.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1324-1329
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• 2007

Resveratrol (3,5,4'-trihydroxystilbene) is a naturally occurring, multi-biofunctional chemical existing in grapes and various other plants as a polyphenol type, and it is one of the best known natural anticancer and antiatherosclerosis reagents. In this study, we investigated the antifungal action by resveratrol in Candida albicans, which is a human infectious fungi as an agent of candidiasis. Resveratrol displayed potent fungicidal activity in an energy-dependent manner, without any hemolytic effects against human erythrocytes. It was found that the serum-induced mycelial forms, which playa crucial role in the pathogenesis of C. albicans during host tissue invasion, were disrupted by resveratrol. To understand the correlation between lethal effects and resveratrol action, we examined the physiological changes of C. albicans. A significant accumulation of intracellular trehalose was induced by stress responses to resveratrol action, and a remarkable arrest of cell-cycle processes at the S-phase in C. albicans occured. Therefore, the fungicidal effects of resveratrol demonstrate that this compound is a potential candidate as an antifungal agent in treating infectious diseases by candidal infections.

• Korean Journal of Pharmacognosy
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• v.5 no.3
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• pp.147-154
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• 1974

Some crude drugs in ancient literatures have been used as traditional therapeutic agent of leucorrhea mainly caused by Trichomonas vaginalis and Candida albicans. Sixty six kinds of crude drugs in ancient literatures and ten constituents were selected as sample drugs. Trichomycin standard was tested to compare with the above drugs. To determine the anti-fungal effect of these drugs on Candida albicans Yu 1200, a test organism, screening test was conducted. Antifungal activities of crude drug water extracts were observed by means of two test methods : firstly through the agar slant method and secondly the counting chamber method which was used for acknowledged drug agents upon the result of the agar slant method. And in order to improve the fungicidal effect, the organisms were stained with 0.02% methylene blue solution. The results of the above test indicated that Fritillariae Rhizoma has antifungal action in the concentration of 310mcg/ml, Coptidis Rhizoma in 620mcg/ml, Meliae Cortex, Scutellariae Radix both in 5,000mcg/ml. Baicalin, catechol among the pure isolated constituents inhibited in the range of 50mcg/ml. This score was based on 50% inhibition in comparison with amounts of control organisms. Rhei Rhizoma, Mori Radicis Cortex, Linderae Radix, and Amomi globosi Fructus showed the antifungal effect moderately in 5,000mcg/ml, and baicalein and pectolinarin in 50mcg/ml in the limit of between 35% and 50% antifungal activity. Staining with 0.02% methylene blue showed that any of the crude drug extracts was unable to stain the cells, but trichomycin in 0.86unit/ml able to stain 12% of the cells. This result means that crude drugs probably do not have fungicidal but fungistatic action.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.672-674
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• 1999

Cepacidine A was first identified as a novel antifungal antibiotic which was isolated from the culture broth of Pseudomonas cepacia AF200l. It showed a potent in vitro antifungal activity against various pathogenic fungi, but did not show any activity against bacteria. Recently, the immunosuppressive action of cepacidine A was discovered using an in vitro screening system involving inhibition of the proliferation of murine lymphocytes stimulated by 2 mitogens, and also by in vivo mouse models involving inhibition of delayed type hypersensitivity and SRBC hemagglutination. Cepacidine A showed a significant activity of cellular immunosuppression (ED/sub 50/) at concentration levels of 1-3 ㎎/㎏, i.p.. Unfortunately, the delayed toxicity at a dose of above 3 ㎎/㎏ i.p. was apparent.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1086-1093
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• 2018

Honokiol, a bioactive compound isolated from the cone and bark of Magnolia officinalis, has been shown to have various activities including inhibition of the growth of Candida albicans. We investigated the roles of the Hsp90-calcineurin pathway in the antifungal activity of honokiol. The pharmacologic tool was employed to evaluate the effects of Hsp90 and calcineurin in the antifungal activity of honokiol. We also evaluated the protective effects of the calcineurin inhibitor cyclosporin A (CsA) on honokiol-induced mitochondrial dysfunction by the fluorescence staining method. The Hsp90 inhibitor potentiated the antifungal activity of honokiol. A C. albicans strain with the calcineurin gene deleted displayed enhanced sensitivity to honokiol. However, co-treatment with calcineurin inhibitor CsA attenuated the cytotoxic activity of honokiol due to the protective effect on mitochondria. Our results provide insight into the action mechanism of honokiol.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.525-530
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• 1998

Antifungal activities of cinnamaldehyde derivatives against various fungi were investigated using paper disc diffusion method. Among the derivatives tested, ${\alpha}-chlorocinnamaldehyde$ was stronger than cinnamaldehyde in antifungal activity and was effective in inhibiting the growth of the representative fungi of dermatomycosis with minimum inhibitory concentration of $9.76{\sim}19.5\;{\mu}g/ml$. A comparison of antifungal activity of cinnamaldehyde derivatives revealed that antifungal action of cinnamaldehyde might be related to a basic structure of acrolein.

• Molecules and Cells
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• v.28 no.5
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• pp.473-477
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• 2009

Previously, the 9-mer analog peptides, 9Pbw2 and 9Pbw4, were designed based on a defensin-like peptide, protaetiamycine isolated from Protaetia brevitarsis. In this study, antifungal effects of the analog peptides were investigated. The antifungal susceptibility testing exhibited that 9Pbw4 contained more potent antifungal activities than 9Pbw2. A PI influx assay confirmed the effects of the analog peptides and demonstrated that the peptides exerted their activity by a membrane-active mechanism, in an energy-independent manner. As the noteworthy potency of 9Pbw4, the mechanism(s) of 9Pbw4 were further investigated. The membrane studies, using rhodamine-labeled giant unilamellar vesicle (GUV) and fluorescein isothiocyanate (FITC)-dextran loaded liposome, suggested that the membrane-active mechanism of 9Pbw4 could have originated from the pore-forming action and the radii of pores was presumed to be anywhere from 1.8 nm to 3.3 nm. These results were confirmed by 3D-flow cytometric contour-plot analysis. The present study suggests a potential of 9Pbw4 as a novel antifungal peptide.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.420-425
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• 2010

The antifungal effects and action mechanisms of styraxjaponoside A and B were investigated. Devoid of hemolytic effect, the compounds had significant effect against several human pathogenic fungal strains, with energy-independent manners. To understand the action mechanisms of the compounds, the flow cytometric analysis plotting the forward scatter and the side scatter, $DiBAC_4$(3) staining and DPH fluorescence analysis were conducted. The results indicated that the actions of the compounds were dependent upon the membrane-active mechanisms. The present study suggests that styraxjaponoside A and B exert their antimicrobial effects via membrane-disruptive mechanisms.