Dissipation and the effects of thidiazuron on antioxidant enzyme activity and malondialdehyde content in strawberry.

Abstract

Increasing numbers of fruit swelling agents have been used to improve the fruit rate and production yield of strawberries in recent years. The abuse of fruit swelling agents could lead to an increase in the deformation rate and abnormal coloration of strawberry and a decrease in quality at harvest. Therefore, understanding the harmful effects of fruit swelling agents on strawberry will provide guidance for their reasonable use. The residual determination method for measuring thidiazuron (TDZ) in strawberry was developed and validated by liquid chromatography and tandem mass spectrometry (LC-MS/MS). The recoveries of TDZ in strawberry were 97.9-108.5% with relative standard deviations of 0.9% to 5.3%. The dissipation rates of TDZ were different in strawberries cultivated under field and indoor conditions due to the differences in temperature and humidity. The ascorbic acid content increased when TDZ was applied at 2mg kg-1 . The SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase) activities of strawberry tended to decrease and subsequently increase following the application of TDZ, and the opposite changes occurred on the malondialdehyde (MDA) content of TDZ-treated strawberry. The analytical method for measuring TDZ in strawberry that was developed was suitable for dissipation studies on this compound. Antioxidant enzyme activities and the MDA content of strawberry were altered, and some reverse effects, such as membrane damage, were inhibited when TDZ was applied. The data obtained in this study might provide suggestions to reduce the adverse effects of TDZ on strawberry and may help to guide the safe and proper use of TDZ in strawberry. © 2019 Society of Chemical Industry.