Metabolomic analysis of black sesame seeds: Effects of processing and active compounds in antioxidant and anti-inflammatory properties

Black sesame seeds (BSS) have been recognized as a functional food due to their nutritional and therapeutic value for many years. In China, BSS is traditionally processed and consumed through two methods, namely, nine steaming nine sun-drying and stir-frying. The present study aimed to evaluate the effects of these processing techniques on the antioxidant and anti-inflammatory activities of BSS. UPLC-QTOF/MS was used for untargeted metabolomics to analyze the composition changes. The results indicated that the different samples had good antioxidant and anti-inflammatory activities, but thermal treatment reduced their activities. Untargeted metabolomics identified a total of 196 metabolites. Molecular docking studies targeting proteins associated with inflammation (iNOS) demonstrated that compounds acting as inhibitors were significantly reduced under both treatments. These results indicate that both nine steaming nine sun-drying and stir-frying lead to substantial loss of antioxidant, anti-inflammatory, and bioactive metabolites in BSS, which provides an important reference for its rational utilization.