Abstract Phytochemical analysis of a crude ethyl acetate (EtOAc) extract derived from endophytic fungus Fusarium verticillioides strain WF18 afforded one new polyketide metabolite, fusaisocoumarin A (1), along with two known compounds, emodin (2) and sesquiterpenoid phytohormone (+)-abscisic acid (ABA) (3). Chemical structures of isolated compounds were elucidated based on HRESIMS together with 1D- and 2D-NMR spectroscopic analyses. Interestingly, all isolated compounds revealed pronounced antifungal activity against certain endophytic fungal strains namely; Aspergillus austroafricanus strain Eis.1, Aspergillus versicolor strain EIS2, Phoma fungicola strain AT100, Aspergillus tubingensis strain AN103 along with Candida albicans ATCC 90029 with MIC (minimum inhibitory concentration) range from 0.3 to 1.3 µg/mL. The biosynthesis of antifungal compounds and the phytohormone (+)-abscisic acid (ABA) illustrates an example of the crosstalks between the host plant and its endophyte in which the endophytic fungus produces metabolites defending the host plant against environmental stresses and also against other fungal phytopathogens.

中文翻译：

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内生真菌轮枝镰孢 WF18 菌株的抗真菌代谢物

摘要 对来自内生真菌轮枝镰孢 WF18 菌株的粗乙酸乙酯 (EtOAc) 提取物进行植物化学分析，得到了一种新的聚酮化合物代谢物 Fusaisocoumarin A (1)，以及两种已知化合物大黄素 (2) 和倍半萜类植物激素 (+)-脱落酸 (ABA) (3)。基于 HRESIMS 以及 1D-和 2D-​​NMR 光谱分析阐明了分离化合物的化学结构。有趣的是，所有分离的化合物都显示出对某些内生真菌菌株的显着抗真菌活性，即；澳大利亚曲霉菌株 Eis.1、杂色曲霉菌株 EIS2、真菌真菌菌株 AT100、塔宾曲霉菌株 AN103 以及白色念珠菌 ATCC 90029 的 MIC（最低抑制浓度）范围为 0.3 至 1.3 µg/mL。