Widely-targeted metabolomics reveals phased metabolic response underlying light-induced quality deterioration of dried Dendrobium huoshanense petals in storage

Dendrobium huoshanense dried petals are prone to light-induced color fading during storage, compromising their commercial and functional value. This study employed UPLC-MS/MS-based widely-targeted metabolomics to analyze metabolic dynamics of petals under 6000 ± 10 Lux light for 18 days by accelerated test. A total of 3173 metabolites were identified, with 625 differential metabolites (DMs) clustered into six expression patterns. Further screening yielded 78 core DMs (89.7% up-regulated), involving flavonoids, terpenoids, lipids, and alkaloids. Functional annotation revealed three coordinated modules: antioxidant defense, lipid membrane homeostasis, and specialized metabolite allocation. Stage-specific analysis mainly uncovered phased responses including acute defense, precise adaptation, recovery, and homeostasis consolidation. This study clarifies the metabolomics process and molecular basis of light-induced quality alteration, providing theoretical support for targeted post-harvest storage of D. huoshanense petals. • The color of Dendrobium huoshanense petals will fade to grayish-white under light. • A total of 78 core differential metabolites in this process were screened out. • This process involves phased metabolic responses such as acute defense. • The antioxidant defense and membrane homeostasis are the main functional modules.