Arcopilus aureus MaC7A as a New Source of Resveratrol: Assessment of Amino Acid Precursors, Volatiles, and Fungal Enzymes for Boosting Resveratrol Production in Batch Cultures.

Featured Application: The synthesis of the nutraceutical resveratrol by filamentous fungi represents a new and exciting area for bioprocess research. Considering that resveratrol was initially placed as a natural phytoalexin from plants, its biosynthesis by fungi may be regulated by several factors including a broad spectrum of small molecules and enzymes involved in chemical defense. This work reports on the effect of some elicitors that promote resveratrol biosynthesis in fungi and how they can be used to produce this stilbene under controlled conditions. The chemical factors that regulate the synthesis of resveratrol (RV) in filamentous fungi are still unknown. This work reports on the RV production by Arcopilus aureus MaC7A under controlled conditions and the effect of amino acid precursors (PHE and TYR), monoterpenes (limonone, camphor, citral, thymol, menthol), and mixtures of hydrolytic enzymes (Glucanex) as elicitors for boosting fungal RV. Batch cultures with variable concentrations of PHE and TYR (50–500 mg L⁻¹) stimulated RV production from 127.9 ± 4.6 to 221.8 ± 5.2 mg L⁻¹ in basic cultures developed in PDB (pH 7) added with 10 g L⁻¹ peptone at 30 °C. Maximum levels of RV and biomass were maintained during days 6–8 under these conditions, whereas a dramatic RV decrease was observed from days 10–12 without any loss of biomass. Among the tested volatiles, citral (50 mg L⁻¹) enhanced RV production until 187.8 ± 2.2 mg L⁻¹ in basic cultures, but better results were obtained with Glucanex (100 mg L⁻¹; 198.3 ± 7.6 mg L⁻¹ RV). Optimized batch cultures containing TYR (200 mg L⁻¹), citral (50 mg L⁻¹), thymol (50 mg L⁻¹), and Glucanex (100 mg L⁻¹) produced up to 237.6 ± 4.7 mg L⁻¹ of RV. Our results suggest that low concentrations of volatiles and mixtures of isoenzymes with β-1, 3 glucanase activity increase the biosynthesis of fungal RV produced by A. aureus MaC7A in batch cultures. [ABSTRACT FROM AUTHOR]