Blue Light Induces Cultivar-Specific Metabolic Reprogramming of Bioactive Compounds in Chinese Cabbage Revealed by...

Chinese cabbage is a widely cultivated leafy vegetable with high nutritional value. Contains high levels of vitamin C, dietary fiber, and phytochemical antioxidants, and plays an important role in human nutrition. In this study, the common cultivar 14S23 was used as a control, and two orange-red heart cultivars (15S1094 and 20S530) were exposed to blue light (300 μmol m^-2 s^-1) for 3 or 6 h to elucidate the effects of blue light on nutritional quality and underlying regulatory mechanisms. Results demonstrated clear cultivar-specific differences in antioxidant capacity and metabolic responses under blue light. Compared with 14S23, 15S1094 and 20S530 showed significantly higher activities of ascorbate peroxidase (APX), glutathione peroxidase (GPX), and glutathione reductase (GR), as well as greater total antioxidant capacity. Prolonged exposure further enhanced these effects, with the 6 h treatment showing stronger responses than the 3 h. Widely targeted metabolomics analysis showed that blue light induced extensive metabolic reprogramming across cultivars. In particular, amino acids and their derivatives, alkaloids, lignans, coumarins, and specific lipids accumulated to higher levels in 15S1094 and 20S530 than in 14S23. These metabolic changes were associated with enhanced antioxidant capacity and improved nutritional quality. Overall, this study provides new insights into the physiological and metabolic mechanisms underlying blue light-enhanced vegetable quality and offers a basis for developing sustainable strategies to improve postharvest quality in leafy vegetables.