The Antiphytopathogenic Metabolites and the Synergy of Endophytes sp., from the Same Host.

Two endophytes from the same host were isolated and cultured separately. Three new eremophilane sesquiterpenoids (), three new furan derivates (, -), one new polyketide (), and four known compounds (, , , ) from sp. and two new 10-membered macrolides (-), a new liner polyketide (), a new benzofuran (), and six known compounds (-) from were isolated. The structures of the isolated compounds were determined by spectroscopic methods, NMR calculations, and ECD calculations. The compounds -, -, , and - showed significant antiphytopathogenic effects against mycotoxigenic sp. comparable to the activity of nystatin (positive control). Compounds , , , , and indicated inhibitions against phytopathogen with MICs < 10 μg/mL. In addition, the compounds with weak antifungal activities from two endophytes were mixed to test their antifungal activity. The results showed that the metabolites from two endophytes had synergistic antifungal effects, and the beneficial interactions between natural products can induce more antifungal effects against plant pathogens than that of single compounds.