Postharvest quality and reactive oxygen species metabolism improvement of Coprinus comatus mushroom using allyl isothiocyanate fumigation

The aim of this study was to evaluate the effect of allyl isothiocyanate (AITC) on the reactive oxygen species (ROS) metabolism and quality of postharvest Coprinus comatus (C. comatus). Fresh mushrooms were stored at 4 degrees C with AITC at 5, 10, and 20 mu L/L for 18 d, respectively. Sampling was performed every 3 d, and physicochemical parameters and ROS metabolism related enzymes activities were analyzed. Compared with the control, the application of AITC at 10 mu L/L significantly (P<0.05) decreased xanthine oxidase activity after 9 d of storage, while it significantly (P<0.05) improved the activities of succinic dehydrogenase, glutathione reductase, peroxidase, catalase, and ascorbate peroxidase in the middle and later stages of storage. Furthermore, the Ca2+-ATPase and superoxide dismutase activities in sample treated by 10 mu L/L were all significantly (P<0.05) higher than those in the control. Therefore, the accumulation trends of malondialdehyde and ROS were retarded and membrane integrity was maintained. However, high-concentration AITC (20 mu L/L) treatment accelerated the ROS generation and increased electrolyte leakage rate. All AITC treatments significantly (P<0.05) inhibited the respiration rate during the first 9 d of storage and retarded browning of C. comatus during the storage of 18 d. These findings suggested that AITC treatment would be a promising method to maintain C. comatus quality, but the concentrations need to be optimized.