Antifungal metabolites of endophytic fungi

Abstract

Not only medicinal plants, but also the endophytic fungi that colonize them are excellent sources of antifungal metabolites. In some cases, the substances detected in plants have been shown to be secondary metabolites synthesized by their fungal inhabitants. As we have shown, most endophytic fungi produce biologically active metabolites, many of which are antifungal. We speculate that in situ these antifungal metabolites protect the endophytic fungi from competitors within the plant host. The metabolites belong to diverse structural groups and include many unprecedented carbon skeletons, but also derivatives of known structural groups: the benzofuranes, biaryl ethers, botryanes, coniothyriomycins, dinemasones, epoxydon derivatives, fusidilactones, isocoumarins, massarilactones, palmarumycins, pestalotheols, pyranocines, pyrenocines, naphthalenes, oblongolides and xanthones. The chemical diversity of the fungal metabolites by functional group transformation and the quality of diversity by ring closure of open-chain compounds and dimerization is demonstrated with examples from our research. We conclude that endophytic fungi are creative masters of chemical synthesis.