Biofumigation with volatile organic compounds from Streptomyces alboflavus TD‐1 and pure chemicals to control Aspergillus ochraceus

The antagonistic activity of volatile compounds from Streptomyces alboflavus TD‐1 against Aspergillus ochraceus were investigated in this study. Conidial germination and mycelial growth of A. ochraceus were completely suppressed after exposure to 40 and 80 g/L of wheat bran cultures of S. alboflavus TD‐1. A total of 35 compounds (relative peak area [RA] >0.10) were identified from wheat bran cultures of S. alboflavus TD‐1. Five standard compounds were purchased for the antifungal activity assay: anisole, dimethyl trisulfide, β‐pinene, benzenamine and 1,5‐cyclooctadiene. Among these, dimethyl trisulfide and benzenamine showed strong inhibitory effects on the mycelial growth of A. ochraceus . In addition, conidial and hyphal morphological abnormalities were observed in treated A. ochraceus . Scanning electron microscopy (SEM) and OD‐260 nm absorption analysis demonstrated that disruption of membrane integrity may be a possible mechanism of action for volatiles from S. alboflavus TD‐1. This study indicates that volatiles of S. alboflavus TD‐1 have tremendous potential to act as a strategy for the biocontrol of postharvest diseases in food during storage.