BACKGROUND: There is no guideline for the appropriate wavelength at which to measure the optical density (OD) value in broth microdilution antifungal susceptibility testing, although a spectrophotometric reading method is commonly used. The present study aimed to analyze the difference in the OD values over the range of visible light and to ascertain the optimal wavelength for the spectrophotometric method of microdilution testing. METHODS: We measured the OD of background blank controls of broth medium, antifungal agents, and inocula of five type strains using a Synergy HT multi-detection microplate reader at 5-nm intervals from 380 nm to 760 nm. We also estimated the OD differences between the 50% of growth control and blank control. RESULTS: The OD of the blank control showed a parabola shape with two peaks and steadily decreased at longer wavelengths. The curves of the antifungal agent were similar to those of blank controls, and the influence of each antifungal agent on the OD was minimal. For the difference in OD between 50% of growth control and the blank control, the curve was the opposite of the blank control, and the OD increased steadily at the wavelengths above 600 nm. CONCLUSIONS: The range between 600 nm and 700 nm was the optimal wavelength for broth microdilution antifungal susceptibility testing, although any wavelength within the visible light spectrum can be used.
Antifungal Agents/*chemistry ; Azoles/*chemistry ; Culture Media/*chemistry ; Flucytosine/*chemistry ; Microbial Sensitivity Tests ; Spectrophotometry/*methods

We isolated a high efficient antifungal strain A02 from forest soil in a suburb of Beijing. The result of polyphasic taxonomy confirmed that strain A02 belongs to Streptomyces lydicus. The fermented broth of the strain presented a stable and strong inhibiting activity against many plant pathogenic fungi. The purpose of this study was to ascertain the substance base of the antifungal activity of strain A02. We extracted the antifungal metabolite of A02 by using column chromatography with X-5 macroporous resin and 100-200 mesh silica gel respectively, and then purified it by LC-9101 recycling preparative HPLC with a SP-120-15 column (JAIGEL-ODS-AP). An active compound with purity over 99.845% was finally obtained. The chemical structure of the active compound was determined with spectroscopy methods, including ultraviolet spectrometry, infrared spectrometry, high resolution mass spectrometry and nuclear magnetic resonance. According to the analysis results, we identified the active compound as a tetraene macrolide antibiotic with the molecular weight of 665, the molecular formula C33H47No3 and the same chemical structure as natamycin. Our research revealed a new biosynthetic function for S. lydicus to produce natamycin, and an expanding application field for natamycin to be used for the control of fungal plant diseases.
Antifungal Agents ; chemistry ; isolation & purification ; Natamycin ; analogs & derivatives ; Soil Microbiology ; Streptomyces ; chemistry ; isolation & purification ; metabolism

The incidence of systemic fungal infections have increased dramatically, moreover, drug resistance including either primary (intrinsic) or secondary (acquired) resistance, becomes one of the main reasons accounting for the failure of treating invasive fungal infections in the past decades. Nowadays, clinically available antifungal drugs are limited and their combination in antifungal therapy was not effective. It is expected to be a new strategy to synergistically sensitize antifungal drugs against drug-resistant fungi by using new small molecules. Based on the study in our research group and the reported work of others, we reviewed the research of the natural products which have synergistic effect with the antifungal agents against drug-resistant fungi. This review focused on the resource, structure, pharmacological activity, and action mechanism of the compounds, as well as somewhat in common, and would provide theoretical base for seeking new drug against drug-resistance fungi.
Antifungal Agents ; chemistry ; pharmacology ; Biological Products ; chemistry ; pharmacology ; Drug Synergism ; Fungi ; drug effects

Artemisia argyi (A. argyi), a plant with a longstanding history as a raw material for traditional medicine and functional diets in Asia, has been used traditionally to bathe and soak feet for its disinfectant and itch-relieving properties. Despite its widespread use, scientific evidence validating the antifungal efficacy of A. argyi water extract (AAWE) against dermatophytes, particularly Trichophyton rubrum, Trichophyton mentagrophytes, and Microsporum gypseum, remains limited. This study aimed to substantiate the scientific basis of the folkloric use of A. argyi by evaluating the antifungal effects and the underlying molecular mechanisms of its active subfraction against dermatophytes. The results indicated that AAWE exhibited excellent antifungal effects against the three aforementioned dermatophyte species. The subfraction AAWE6, isolated using D101 macroporous resin, emerged as the most potent subfraction. The minimum inhibitory concentrations (MICs) of AAWE6 against T. rubrum, M. gypseum, and T. mentagrophytes were 312.5, 312.5, and 625 μg·mL^-1, respectively. Transmission electron microscopy (TEM) results and assays of enzymes linked to cell wall integrity and cell membrane function indicated that AAWE6 could penetrate the external protective barrier of T. rubrum, creating breaches ("small holes"), and disrupt the internal mitochondrial structure ("granary"). Furthermore, transcriptome data, quantitative real-time PCR (RT-qPCR), and biochemical assays corroborated the severe disruption of mitochondrial function, evidenced by inhibited tricarboxylic acid (TCA) cycle and energy metabolism. Additionally, chemical characterization and molecular docking analyses identified flavonoids, primarily eupatilin (131.16 ± 4.52 mg·g^-1) and jaceosidin (4.17 ± 0.18 mg·g^-1), as the active components of AAWE6. In conclusion, the subfraction AAWE6 from A. argyi exerts antifungal effects against dermatophytes by disrupting mitochondrial morphology and function. This research validates the traditional use of A. argyi and provides scientific support for its anti-dermatophytic applications, as recognized in the Chinese patent (No. ZL202111161301.9).
Antifungal Agents/chemistry* ; Arthrodermataceae ; Artemisia/chemistry* ; Molecular Docking Simulation ; Mitochondria ; Microbial Sensitivity Tests

Four new diphenyl ethers, named epicoccethers K-N (1-4), were purified from the fermentation medium of a fungus Epicoccum sorghinum derived from Myoporum bontioides, and identified through HR-ESI-MS and NMR spectral analysis. Except that compound 1 showed moderate antifungal activity against Penicillium italicum and Fusarium graminearum, the other three compounds showed stronger activity against them than triadimefon. All of them showed moderate or weak antibacterial activity towards Staphylococcus aureus and Escherichia coli with O6 and O78 serotypes except that 3 was inactive to E. coli O6.
Anti-Bacterial Agents/pharmacology* ; Antifungal Agents/chemistry* ; Ascomycota ; Escherichia coli ; Microbial Sensitivity Tests ; Molecular Structure ; Phenyl Ethers/chemistry*

OBJECTIVETo study the antibacterial effect against Candida albicans of the A-2186 silicone elastomer containing nano-TiO2 in vitro.

METHODSAntibacterial agent of nano-TiO2 was added into A-2186 silicone elastomer with incorporating percentages of 0.5%, 1.0%, 1.5%, and 2.0% (W/W). There was no nano-TiO2 in the control group. The antibacterial effect of the A-2186 silicone elastomer was determined using the film contact method with lighting and without lighting.

RESULTSEither with lighting or without lighting, there were significances between the experiment groups and the control group (P < 0.05). When the incorporating percent was 2.0%, the inhibitory effect was the best among the experiment groups. Without lighting, the inhibitory rate was 53.7% and with lighting, the inhibitory rate was 85.9%.

CONCLUSIONSThe A-2186 silicone elastomer containing nano-TiO2 has antibacterial properties against Candida albicans, which enhances with increases of nano-TiO2 percent in the material. With the same incorporating percentage, the antibacterial effect with lighting is better than that without lighting.

Antifungal Agents ; pharmacology ; Candida albicans ; drug effects ; Nanostructures ; Silicone Elastomers ; chemistry ; pharmacology ; Titanium ; pharmacology

OBJECTIVETo determine the contribution of chemical components represented by characteristic peaks of fingerprint of different eluted parts of Euphorbia humifusa to the antifungal effect to provide theoretical basis and data support for the traditional Chinese medicine quality control mode.

METHODHPLC was introduced to analyze fingerprint of different eluted parts of E. humifusa. The antifungal effect was observed using NCCLS M38-A method. The correlation between fingerprint and antifungal effect of E. humifusa was identified using grey relational analysis.

RESULTThe antifungal effect of different eluted parts of E. humifusa is resulted from the combined action of multiple chemical components. Chemical components representing a contribution to pharmacy dynamics were ordered by representative spectrum 2 > 5 > 3 > 4 > 1 for anti-Trichophyton rubrum and anti-T. mentagrophytes 5 > 2 > 3 > 4 > 1.

CONCLUSIONFingerprint of different eluted parts of E. humifusa is related with their antifungal effect to some extent.

Antifungal Agents ; pharmacology ; Chromatography, High Pressure Liquid ; Euphorbia ; chemistry ; Quality Control

Trichoderma spp. is a kind of filamentous fungi with important biocontrol value. Twelve strains of Trichoderma spp. were isolated from the soils of different types of crops in Shaoxing, Zhejiang and Foshan, Guangdong. The antagonistic resistance to Fusarium oxysporum was compared by plate confrontation test. The further analysis of volatile secondary metabolites for two strains were carried out using HS-SPME-GC-MS analysis. The results showed that T. asperellum ZJSX5003 and GDFS1009 had fast growth ability, and the inhibition effects on F. oxysporum were 73% and 74% respectively. Six identical volatile metabolites were detected as follows 2-Methyl-1-propanol, 3-Methyl-1-butanol, 3-Methyl-3-buten-1-ol, Acetyl methyl carbinol, Butane-2,3-diol and 6-n-pentyl-2H-pyran-2-one (6-PAP). Among them, 6-PAP was validated to have a higher inhibitory effect on F. oxysporum in vitro. This study will provide basis for the development of biocontrol agents with metabolites of Trichoderma, such as 6-PAP.
Antibiosis ; Antifungal Agents ; pharmacology ; Fusarium ; drug effects ; physiology ; Gas Chromatography-Mass Spectrometry ; Trichoderma ; chemistry ; metabolism

Currently, the first-line drugs for invasive fungal infections (IFI), such as amphotericin B, fluconazole and itraconazole, have drawbacks including poor water solubility, low bioavailability, and severe side effects. Using drug delivery systems is a promising strategy to improve the efficacy and safety of traditional antifungal therapy. Synthetic and biomimetic carriers have greatly facilitated the development of targeted delivery systems for antifungal drugs. Synthetic carrier drug delivery systems, such as liposomes, nanoparticles, polymer micelles, and microspheres, can improve the physicochemical properties of antifungal drugs, prolong their circulation time, enhance targeting capabilities, and reduce toxic side effects. Cell membrane biomimetic drug delivery systems, such as macrophage or red blood cell membrane-coated drug delivery systems, retain the membrane structure of somatic cells and confer various biological functions and specific targeting abilities to the loaded antifungal drugs, exhibiting better biocompatibility and lower toxicity. This article reviews the development of antifungal drug delivery systems and their application in the treatment of IFI, and also discusses the prospects of novel biomimetic carriers in antifungal drug delivery.
Antifungal Agents/therapeutic use* ; Drug Delivery Systems ; Amphotericin B/therapeutic use* ; Liposomes/chemistry* ; Nanoparticles ; Drug Carriers

The aim of this study was to prepare tandem multimeric proteins of BmSPI38, a silkworm protease inhibitor, with better structural homogeneity, higher activity and stronger antifungal ability by protein engineering. The tandem multimeric proteins of BmSPI38 were prepared by prokaryotic expression technology. The effects of tandem multimerization on the structural homogeneity, inhibitory activity and antifungal ability of BmSPI38 were explored by in-gel activity staining of protease inhibitor, protease inhibition assays and fungal growth inhibition experiments. Activity staining showed that the tandem expression based on the peptide flexible linker greatly improved the structural homogeneity of BmSPI38 protein. Protease inhibition experiments showed that the tandem trimerization and tetramerization based on the linker improved the inhibitory ability of BmSPI38 to microbial proteases. Conidial germination assays showed that His₆-SPI38L-tetramer had stronger inhibition on conidial germination of Beauveria bassiana than that of His₆-SPI38-monomer. Fungal growth inhibition assay showed that the inhibitory ability of BmSPI38 against Saccharomyces cerevisiae and Candida albicans could be enhanced by tandem multimerization. The present study successfully achieved the heterologous active expression of the silkworm protease inhibitor BmSPI38 in Escherichia coli, and confirmed that the structural homogeneity and antifungal ability of BmSPI38 could be enhanced by tandem multimerization. This study provides important theoretical basis and new strategies for cultivating antifungal transgenic silkworm. Moreover, it may promote the exogenous production of BmSPI38 and its application in the medical field.
Animals ; Antifungal Agents/pharmacology* ; Escherichia coli/metabolism* ; Proteins/metabolism* ; Protease Inhibitors/chemistry* ; Bombyx/chemistry* ; Saccharomyces cerevisiae/metabolism* ; Peptide Hydrolases