Production of the antifungal biopesticide physcion through the combination of microbial fermentation and chemical post-treatment.

Physcion is an anthraquinone compound observed dominantly in medicinal herbs. This anthraquinone possesses a variety of pharmaceutically important activities and has been developed to be a widely used antifungal biopesticide. Herein, we report on the effective preparation of 3R-torosachrysone (4), a tetrahydroanthracene precursor of physcion, in Aspergillus oryzae NSAR1 by heterologous expression of related genes mined from the phlegmacins-producing ascomycete Talaromyces sp. F08Z-0631. Conditions for converting 4 into physcion were studied and optimized, leading to the development of a concise approach for extracting high-purity physcion from the alkali-treated fermentation broth of the 4-producing A. oryzae strain.