• 한국약용작물학회지
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• 제13권2호
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• pp.110-114
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• 2005

Extracts from sawdust of Pinus densiflora were showed antifungal activity against Lentinula edodes. It was extracted by hot water and then successively extracted by n-hexane, ethyl acetate, and methanol. The yields of the n-hexane-soluble, ethyl acetatesoluble, methanol-soluble and methanol-insoluble fractions of water extracts were 8.2%, 10.6%, 32.0%, and 49.2%, respectively. The ethyl acetate-soluble fraction showed the greatest antifungal activity against L. edodes: 41.5% inhibition at 1,000 ppm. However, there were not significant differences of antifungal activities between n-hexane-soluble fraction and methanol-soluble fraction at a concentration of 1,000 ppm. The hot water extracts showed 23.5% of antifungal activity against L. edodes at a concentration of 1000 ppm. The four antifungal compounds were separated from ethyl acetate fraction by thin layer chromatography.

• 약학회지
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• 제43권5호
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• pp.566-571
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• 1999

(1H-1,2,4-Triazolyl) methy-4-(sub). phenyl-5-methyl-1,3-dioxolan-2-yliden (3) derivatives were synthesized and tested for their antifungal activities. The designed compounds with a 1,2,4-triazolylmethyl group at the 4-position of 1,3-dioxolan-2-yliden moiety were synthesized by reaction of difluorinated olefins(2) with (2R, 3R)-2-(2,4-dihalophenyl)-1-(1H-1,2,4-triazol-l-yl) butane-2,3-diol (1). These compounds were tested for in vitro antifungal activities against 16 fungi species. The MIC values were determined by the micro broth dilution method. In general, 1,3-dioxolan-2-yliden derivatives showed antifungal activities in vitro. Among them, (4R, 5R)-4-(2,4-difluorophenyl)-5-methyl-2-[1-(3,4-methylenedioxypheny)meth-ylidene)-1,3-dioxolon-4-yl(1H-1,2,4-triazollyl)methane showed superior antifungal activities to fluconazol and ketoconazol.

• 한국미생물·생명공학회지
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• 제24권5호
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• pp.529-533
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• 1996

Melittin (ME) from honeybee venom has a broad range of strong antimicrobial activity, but it has hemolytic activity against eukaryotic cells. In order to design peptides with powerful antifungal activity without cytotoxic property of ME and understand structure-antifungal activity relationships, the hybrid peptides derived from the sequences of ME and cecropin A (CA) or magainin 2 (MA), MA(10-17)ME(1-12) and CA(1-8)ME(1-12). were synthesized by solid phase method. MA(10-17)ME(1-12) showed potent antifungal activity comparable to ME against Fusarium oxysporum with no hemolytic activity against human red blood cells. The hybrid peptides showed strong inhibi- tion of (1, 3)-$\beta$-D-glucan synthase. This result indicates that the antifungal activity of the hybrid peptides against Fusarium oxysporum is attributed to the inhibition of cell wall synthesis. The results therefore showed a successful design of a peptide having antifungal activity without hemolytic property.

• Journal of the Korean Wood Science and Technology
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• 제31권3호
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• pp.70-76
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• 2003

Five isoflavonoids, biochanin A-7-O-β-D-xylopyranosyl-(1⟶6)-β-D-gluco- pyranoside (1), (-)-maackiain (2), calycosin (3), trifolirhizin (4) and genistein (5), were tested for antifungal activity against nine fungi. These compounds were isolated from the wood (compound 1 and 2) and from the bark (compound 3, 4 and 5) of S. japonica. According to the results of antifungal activity test, (-)-maackiain was evaluated as the best antifungal compound among the isolated compounds. In this regard, it could be mentioned that high antifungal activity of S. japonica wood extracts was originated from (-)-maackiain.

• 한국미생물·생명공학회지
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• 제37권3호
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• pp.273-279
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• 2009

형방지황탕은 한의학에서 중요한 약처방으로 인간의 기력 회복에 약효가 탁월한 것으로 알려져 있다. 본 연구에서는 형방지황탕으로부터 항생 물질(HTI)을 분리하여 항진균활성 및 그 작용기작을 검토하였다. 그 결과 각종 병원성 진균에 대해 항진균 활성을 나타내었으며, 인간 적혈구에 대해서는 세포독성이 나타나지 않은 것으로 확인되었다. 또한 캔디다 알비칸스를 대상으로 스트레스 방어기작과 세포 이형성 유도에 HTI이 미치는 영향을 검토한 결과, 트리 할로즈의 증가와 이형성 유도에 영향을 미치는 것으로 나타나 이러한 현상이 항진균활성에 상관관계가 있음을 확인하였으며, 또한 진균의 세포주기에 미치는 영향도 항진균 활성의 요인이 됨을 밝혔다.

• 한국동물위생학회지
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• 제26권1호
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• pp.57-65
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• 2003

The present study was conducted to examine the outbreak state of bovine dermatophytosis in 14 farms(4 dairy farms, 10 Korean indigenous cattle farms) in Gyeongbuk province from November 2000 to November 2001. The causative agents of dermatophytosis was identified by mycological examination. Antifungal susceptibility test of 26 isolates was performed by agar dilution method, using 5 antifungal drugs. Prevalence of bovine dermatophytosis was found to be 13.5%(90/665) in dairy cattle farms and 14.5%(220/1,520) in Korean indigenous cattle farms. The most common age at which this disease occurred was 2-12 months. This disease usually occurred from winter to spring and the occurrence subsequently decreased in the summer. But 4 Korean indigenous cattle farms with poorly hygienic status were occurred all the year round. The causative agent was identified as Trichophyton verrucosum exclusively in these case. Antifungal susceptibility test of T verrucosum (26 strains) was performed by agar dilution method, using 5 antifungal drugs including tolnaftate, griseofulvin, ketoconazole, amphotericin B and terbinafine. All isolates were highly sensitive to 5 antifungal drugs (geometric mean MICs 0.004∼0.032 $\mu\textrm{g}$/$m\ell$). The isolates were the most sensitive to especially tolnaftate.

• 한국임상수의학회지
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• 제18권1호
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• pp.1-6
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• 2001

The aim of this study was to determine optimal therapeutic dose of antifungal agents for dermatophytes. Forty nine dermatophytes were isolated form dogs and cats showing skin lesions and were tested for their in vitro susceptibility to nystatin, griseofulvin, terbinafine, ketoconazole and fluconazole by broth microdilution test. Terbinafine showed the lowest MIC value among the antifungal agents tested, and MIC values ranged from 0.002 to 0.016 $\mu\textrm{g}$/ml. Fluconazole showed the highest MIC values among the antifungal agents tested, and MIC values ranged from 32 to 512 $\mu\textrm{g}$/ml. MIC values of nystatin, griseofulvin and ketoconazole ranged from 1.12 to 4.48 $\mu\textrm{g}$/ml, 0.5 to 4.0 $\mu\textrm{g}$/ml, and 1.6 to 12.8 $\mu\textrm{g}$/ml, resistant to griseofulvin, and that antifungal susceptibility test was needed to determine optimal therapeutic dose of antifungal agents for each dermatophyte.

• The Plant Pathology Journal
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• 제16권4호
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• pp.189-199
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• 2000

To search for the antifungal substances, various actino-mycete isolates were obtained from various soils of Korea using plate dilution method on the humic acid vitamin agar plates. In the screening procedures using a dual culture method, 32 actionomycete isolates were selected, which showed the inhibitory activity against mycelial growth of plant pathogenic fungi Altirnaria mali, Colletotrichum gloeosporides, Fusarium oxysporum f.sp. cucumerinum, Magnaporthe grisea, Phytophthora capsici, and Rhizoctonia solani. Bioassay of the crude extracts from culture filtrates and mycelial mets revealed that 12 antagonistic actionomycetes produced highly active antifungal substances. Actinomycete strain S5-55 which showed the substantial antifungal activity against the tested fungi was selected for production of the antifungal substances. Based on the cytochemical and morphological characteristics, strain S5-55 was identified as a Streptomyces species. The results of the numerical identification using the TAXON program confirmed that Streptomyces strain S5-55 was identical with Streptomyces humidus including in TAXON major cluster 19. The production of antifungal substance was most favorable when S. humidus strain S5-55 was cultivated for 10 dats on soluble starch broth supplemented with $K_2$HPO$_4$. The antifungal substances active against the plant pathogenic fungi P. capsici and M. grisea were partially purified using $\textrm{C}_{18}$ reversed-phase column chromatography.

• Journal of Microbiology and Biotechnology
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• 제20권8호
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• pp.1192-1195
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• 2010

To investigate the influence of the N- or C-terminal regions of pleurocidin (Ple) peptide on antifungal activity, four analogs partially truncated in the N- or C-terminal regions were designed and synthesized. Circular dichroism (CD) spectroscopy demonstrated that all the analogs maintained an alpha-helical structure. The antifungal susceptibility testing also showed that the analogs exhibited antifungal activities against human fungal pathogens, without hemolytic effects against human erythrocytes. The result further indicated that the analogs had discrepant antifungal activities [Ple>Ple (1-22)>Ple (4-25)>Ple (1- 19)>Ple (7-25)] and that N-terminal deletion affected the activities much more than C-terminal deletion. Hydrophobicity [Ple>Ple (1-22)>Ple (4-25)>Ple (1-19)> Ple (7-25)] was thought to have been one of the consistent factors that influenced these activity patterns, rather than the other primary factors like the helicity [Ple>Ple (4-25) >Ple (1-22)>Ple (1-19)>Ple (7-25)] or the net charge [Ple=Ple (4-25)=Ple (7-25)>Ple (1-22)=Ple (1-19)] of the peptides. In conclusion, the hydrophobic amino acids in the N-terminal region of Ple is more crucial for antifungal activity than those in the C-terminal region.

• Journal of Microbiology and Biotechnology
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• 제28권11호
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• pp.1771-1781
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• 2018

The emergence of multidrug-resistant microorganisms, as well as fungal infectious diseases that further threaten health, especially in immunodeficient populations, is a major global problem. The development of new antifungal agents in clinical trials is inferior to the incidence of drug resistance, and the available antifungal agents are restricted. Their mechanisms aim at certain characteristics of the fungus in order to avoid biological similarities with the host. Synthesis of the cell wall and ergosterol are mainly targeted in clinical use. The need for new approaches to antifungal therapeutic agents or development alternatives has increased. This review explores new perspectives on mechanisms to effectively combat fungal infections and effective antifungal activity. The clinical drug have a common feature that ultimately causes caspase-dependent cell death. The drugs-induced cell death pathway is associated with mitochondrial dysfunction, including mitochondrial membrane depolarization and cytochrome c release. This mechanism of action also reveals antimicrobial peptides, the primary effector molecules of innate systems, to highlight new alternatives. Furthermore, drug combination therapy is suggested as another strategy to combat fungal infection. The proposal for a new approach to antifungal agents is not only important from a basic scientific point of view, but will also assist in the selection of molecules for combination therapy.