Modified atmosphere packaging maintains stem quality of Chinese flowering cabbage by restraining postharvest lignification and ROS accumulation

In this study, the impact of modified atmosphere packaging (MAP) on quality, lignin biosynthesis, reactive oxygen species (ROS) metabolism, and microstructures of stem in Chinese flowering cabbages was investigated. Compared with control, MAP treatment retained higher content of protein, total soluble solid, and vitamin C, while lower weight loss rate, carbon dioxide (CO₂) production rate, electrolyte leakage, firmness and hollowing of stems. Lignin content in MAP-treated stems was 1.23-fold higher than that of control stems on the twelfth day. Moreover, MAP treatment inhibited the increasing in cell wall thickness by inhibiting activities of lignin biosynthesis-related enzymes. In addition, MAP suppressed ROS contents, while enhanced levels of ascorbic acid and reduced glutathione through promoting activities of antioxidant enzymes. The above results suggest that maintaining stems quality of Chinese flowering cabbages through MAP treatment is related to prevent lignin accumulation around the vascular tissue and enhance antioxidant capacity.