Curcumin Induces Oxidative Stress in Botrytis cinerea, Resulting in a Reduction in Gray Mold Decay in Kiwifruit

Curcumin exhibits efficient antimicrobial activity; nevertheless, its effect on the postharvest decay of fruit has not been examined. Here, effects of curcumin on the fruit gray mold of kiwifruit infected by Botrytis cinerea were analyzed. Results demonstrated that curcumin induced reactive oxygen species (ROS) production and triggered apoptosis in B. cinerea hyphae. Use of N-acetylcysteine, a ROS scavenger, partially ameliorated the inhibition of curcumin on B. cinerea. The NADPH oxidase inhibitor, diphenyleneiodonium chlorine, abrogated the ROS production induced by curcumin, suggesting that curcumin induces oxidative stress in B. cinerea via a NADPH-oxidase-dependent mechanism. Disease severity of gray mold in curcumin-treated kiwifruit was significantly reduced. The malondialdehyde content decreased while the antioxidant enzyme activity increased in kiwifruit with the application of increasing concentrations of curcumin. Collectively, these results indicate that curcumin can be used to control gray mold and elevate antioxidant activity in kiwifruit.