Metabolomics reveals antioxidant profiles linked to culm coloration, shoot nutritional quality, and oxidative stress response in Phyllostachys violascens variants.

The culms of bamboos for shoots are usually green, while non-green varieties are always used as ornamental plants. However, the metabolic differences in bamboo shoots with varying culm colors remain unclear. Here, the untargeted metabolomic profiles of shoots of three Phyllostachys violascens variants were investigated. Ph. violascens (GC) shoots exhibited significantly higher antioxidant capacity and sugar-to-acid ratio, suggesting better flavor. In contrast, Ph. violascens f. chrysoderma (YC) shoots exhibited increased levels of flavonoids, tannins, glutathione, and oxidative stress markers. In WGCNA analysis, the brown module, which positively correlates with YC shoots, was significantly enriched in ROS metabolism, 2-oxocarboxylic acid metabolism, and amino acid biosynthetic pathways, indicating stress-induced antioxidant synthesis in YC shoots. Collectively, these results suggest that culm coloration may serve as a phenotypic indicator of biochemical adaptations, positioning YC as a bioactivity-rich variant, providing valuable insights for bamboo shoot quality assessment and targeted breeding strategies.