Metabolomic analysis of wild oats and cultivated oats

A wide-targeted metabolomics approach was employed to investigate differences in leaf metabolites between wild and cultivated oats 15 days after heading. A total of 1821 metabolites were detected in both wild and cultivated oats, among which 318 were identified as differential metabolites, spanning 13 categories including phenolic acids (65), flavonoids (59), and amino acids and their derivatives (34). The relative abundances of these metabolites were quantified. The results showed that flavonoids represented the most diverse group, while amino acids and their derivatives exhibited the highest overall abundance. Two metabolites—isorhamnetin-7-O-glucoside (santonin) and apigenin-7-O-(2''-glucuronidyl) glucuronide—were unique to wild oats, whereas 3'-glucosyl-6,7-dihydroxy-N-methyl-benzyltetrahydroisoquinoline, glucosylshikimic acid, and myristoleic acid were unique to cultivated oats. Several detected metabolites, including caffeic acid phenethyl ester, salidroside, and chrysin, are known for their antioxidant, anti-inflammatory, anti-tumor, and antibacterial activities, and their levels were higher in wild oats than in cultivated oats. Fourteen oat alkaloids were identified in both types, with 13 of them reaching their highest concentrations in a local naked oat variety. This study provides a valuable reference for the scientific introduction and comprehensive utilization of wild oat resources.