Antifungal and antifeedant terpenoids from Paraphaeosphaeria sp. cultured by extract of host Ginkgo biloba

摘要

Five undescribed terpenoids including a polyketide-terpenoid hybrid paraphaone, and four eremophilane ses-quiterpenoids, paraphaterpenes A-D, as well as two known compounds were isolated from the endophytic fungus Paraphaeosphaeria sp. cultured by extract of host Ginkgo biloba L. The structures were established by spectro-scopic analyses, and the single-crystal X-ray diffraction. The antifungal activity of Paraphaeosphaeria sp. cultured by extract of G. biloba against the plant pathogen Alternaria alternata was significant and higher than that of PDB medium. Tested compounds indicated antifeedant activities against silkworms with feeding deterrence index at 10-70%. Paraphaone, paraphaterpenes A, C, D and alternariol methyl ether showed significant antifungal ac-tivities against the phytopathogens A. alternata, Aspergillus fumigatus, and entomopathogen Beauveria bassiana with MICs <= 4 mu g/mL. And the preliminary structure-activity relationship of eremophilane sesquiterpenoids was exhibited. The culture of Paraphaeosphaeria sp. by host G. biloba medium afforded agricultural antibiotics.

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