• 한국미생물·생명공학회지
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• 제24권3호
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• pp.261-267
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• 1996

To examine the potential utilization of chitosan, the biodegradable natural polymer, as a control agent of apple white rot caused by Botryosphaeria dothidea in a new control measure by coating it on the diseased branches, the various antifungal activities of chitosan was investigated. Chitosan showed significant inhibitory effect on the mycelial growth of B. dothidea, along with the morphological changes including hyphal swelling and ultrastructural changes on solid PDA medium. In liquid PD broth medium, the chitosan showed more significant effect on the growth of B. dothidea also forming cell clusters indicating affection on the hyphal extension. The growth of B. dothidea was inhibited more than 90% at the concentration of 1.0 mg/ml. Chitosan also detained the spore germination and induced the morphological change of germ tubes. Glucosamine, monomer of chitosan, did not affect on the growth of B. dothidea indicating the antifungal activity was caused by chitosan polymer.

• The Korean Journal of Ecology
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• 제20권3호
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• pp.181-189
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• 1997

Phenolic compounds from 7 species of naturalized invader species and Korean wild plants were analyzed by high performance liquid chromatography. Eleven phenolic compounds including benzoic acid were identified. The extract of naturalized plants was significantly more inhibitory to seed germination and seedling growth of the both naturalized and Korean wild plants. The content of total phenolic compounds in each extract were 43.5 mg/l in Ailanthus altissima as the maximum amount and 25.5 mg/l in Phytolacca americana as the minimum. Phytotoxic substances of ethanol extracts was investigated for antifungal activity against 23 selected fungus species. The antifungal activity of Phytolacca americana showed the greatest clear zone of 23 mm in Aspergillus awamori and its activity had an effect against 6 fungus species. Ailanthus altissima formed the greatest clear zone of 26 mm in Erwinia carotovora sub. sp. carotovora and had an effect agsinst 2 fungus species.

• 약학회지
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• 제55권3호
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• pp.227-233
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• 2011

We previously reported the protein isolated from Coptidis Rhizoma (CRP), which has antifungal activity against a fungal pathogen, Candida albicans. In the current study, we investigated what portion in the CRP is responsible for the antifungal activity. For the investigation, the CRP was fractionated on a Shepadex G-50 column. Data resulting from the fractionation, seven fractions were obtained. Fractions (Fr.) I, II, and III eluted initially from the column showed no inhibitory effect on the growth of C. albicans, whereas Fr. IV, V, and VI eluted later revealed inhibition of the growth, and Fr. IV and VI showed potent antifungal activity by broth susceptibility analysis. However, Fr. VI was contained in the CRP more than Fr. IV, which led us to select the VI for the following experiments. In a murine model of a subcutaneous candidiasis caused by C. albicans, the Fr. VI displayed a therapeutic effect on nude mice pretreated with anti-neutrophil monoclonal antibody (RB68C5) and then infected subcutaneously with live C. albicans. At day 16, these mice were healed almost up to 78% of the infected area when compared to infected area of control nude mice that received diluent (Dulbecco's Phosphate-Buffered Saline; DPBS), instead of the Fr. VI (P<0.01). The Fr. VI blocked hyphal formation from blastoconidial form of C. albicans (P<0.01), which might prevent penetration of hyphae to the deeper site of skin and thus helps the healing. In the ionic strength test, the effect of Fr. was influenced by $Ca^{2+}$ ion just like other known antimicrobial peptides, but the influence was affected at an extremely high concentration such as 500 mM. Thus, such ion-concentration is considered to be meaningless in the clinical situation. Considering all data together, Coptidis Rhizoma is appeared to produce an antimicrobial peptide that has therapeutic effect on subcutaneous infection caused by C. albicans.

• 한국균학회지
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• 제29권2호
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• pp.104-109
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• 2001

Polyphosphate의 Candida albicans와 Trichophyton mentagrophytes에 대한 항진균 작용에 대하여 연구하였다. 평균 사슬길이가 15, 45, 75인 polyphosphate는 진균에 대하여 성장억제 효과를 나타낸 반면, pyrophosphate는 성장억제 효과가 없었다. 사슬길이가 증가함에 따라서 진균 성장억제 효과가 증가하는 것으로 관찰되었으며 $800\;{\mu}g/ml$ 농도에서는 균주의 성장을 완전히 억제시켰다. $Mg^{2+}$나 $Ca^{2+}$의 첨가는 polyphosphate의 성장억제 효과를 감소시켰다. Polyphosphate를 처리한 C. albicans에서는 핵산물질의 유리가 관찰되었으며, 세포 swelling이나 표면돌출과 같은 세포형태 변화도 관찰되었다. 세포막 불투과성 물질인 propidium iodide는 Polyphosphate를 처리한 C. albicans의 핵을 염색하는 것이 관찰되었다. Polyphosphate의 항진균 작용은 polyphosphate가 진균 세포벽이나 세포막의 필수 양이온에 대한 chelation 효과에 의한 것으로 사려된다.

• Mycobiology
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• 제33권4호
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• pp.210-214
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• 2005

More than 120 isolates of lactic acid bacteria obtained from Kimchi was screened for antifungal activity against Aspergillus fumigatus. Approximately 10% of the isolates showed inhibitory activity and only 4.16% (five isolates) exhibited strong activity against the indicator fungus A. fumigatus. The five isolates showed a wide rang of antifungal activity against A. flavus, Fusarium moniliforme, Penicillium commune, and Rhizopus oryzae. They were identified by 16S rDNA sequencing as Lactobacillus cruvatus, L. lactis subsp. lactis, L. casei, L. pentosus, and L. sakei. The effect of Lactobacillus on mycelial growth and fungal biomass as well as its ability to produce toxic compounds were determined. The results indicate that the three species, Lactobacillus casei, L. lactis subsp. lactis, and L. pentosus, are active against A. fumigatus.

• Journal of Microbiology and Biotechnology
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• 제28권7호
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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.

• Journal of Microbiology and Biotechnology
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• 제25권8호
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• pp.1257-1264
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• 2015

Trichoderma strain T-33 has been demonstrated to have inhibitory effect on the fungus species Cytospora chrysosperma. Here, an active antifungal compound was obtained from Trichoderma strain T-33 extract via combined separation technologies, including organic solvent extraction, liquid chromatography, and thin-layer chromatography. The purified compound was further characterized by advanced analytical technologies to elucidate its chemical structure. Results indicated that the active antifungal compound in Trichoderma strain T-33 extract is 2,5-cyclohexadiene-1,4-dione-2,6-bis (1,1-dimethylethyl).

• Mycobiology
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• 제49권5호
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• pp.498-506
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• 2021

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 ℃ for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae.

• 대한화학회지
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• 제34권5호
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• pp.476-482
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• 1990

3-phenyl-5,5-dimethyloxazolidine-2,4-dione에 대한 형태 분석을 통하여 구조-활성 관계를 검토하였다. Antifungal Activity에 대한 구조적인 특징으로 활성기인 amide group(-NCO)와 벤젠 moiety가 존재하며, 강한 활성을 나타내는 유사체의 N원자와 para 치환기 간의 공간거리 N-X$_4$는 5.32∼5.37${\AA}$, 3,5-치환기 간의 거리 X$_3$-X$_5$는 5.59 ∼ 5.77 ${\AA}$을 나타내었다.

• Mycobiology
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• 제40권1호
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• pp.53-58
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• 2012

This research is concerned with the fungicidal properties of nano-size silver colloidal solution used as an agent for antifungal treatment of various plant pathogens. We used WA-CV-WA13B, WA-AT-WB13R, and WA-PR-WB13R silver nanoparticles (AgNPs) at concentrations of 10, 25, 50, and 100 ppm. Eighteen different plant pathogenic fungi were treated with these AgNPs on potato dextrose agar (PDA), malt extract agar, and corn meal agar plates. We calculated fungal inhibition in order to evaluate the antifungal efficacy of silver nanoparticles against pathogens. The results indicated that AgNPs possess antifungal properties against these plant pathogens at various levels. Treatment with WA-CV-WB13R AgNPs resulted in maximum inhibition of most fungi. Results also showed that the most significant inhibition of plant pathogenic fungi was observed on PDA and 100 ppm of AgNPs.