Effect of an antifungal peptide from oyster enzymatic hydrolysates for control of gray mold (Botrytis cinerea) on harvested strawberries

A novel peptide CgPep33, with high inhibitory activity against Botrytis cinerea growth has been isolated from enzymatic hydrolysates from the Pacific oyster (Crassostrea gigas), and purified by DEAE Sephadex A-25 ion exchange, Sephadex G-25 gel filtration and HPLC. CgPep33 inhibited the in vitro growth of B. cinerea by 50% at 20–40 μg mL−1 and by 100% at 120 μg mL−1. The disease incidence and lesion diameter of CgPep33-treated fruit were 76% and 6.3 mm, respectively, lower than that of the fruit without CgPep33 treatment on the 3rd day after inoculation. The results suggest that this peptide should provide an alternative to fungicides for controlling postharvest disease.