Phenolic compound, anthocyanin content, and antioxidant activity in some parts of purple waxy corn across maturity stages and locations

The understanding on growth stage of purple waxy corn and location effect is very important for anthocyanin production systems. Therefore, the objective of this study was to evaluate phenolic compounds, anthocyanins and antioxidant activity in corn components at immaturity (22 days after pollination (DAP)) and maturity (36 DAS) stages at different growing locations. Two varieties of purple waxy corn were evaluated at two locations during the dry season 2014/2015. Total phenolic (TPC), total anthocyanin (TAC) and antioxidant activity by DPPH free-radical-scavenging assay and TEAC trolox equivalent antioxidant capacity assay were recorded. Significant differences among corn components (C) were observed for all parameters. Location (L) x Variety (V), LxC, VxC and LxVxC interactions were significant for TAC in both stages. Silk and tassel had the highest TPC at immaturity stage but husk of KND and FC111 at KK had the highest at maturity stage. Silk of KND had the highest TAC at KK at immaturity stage but cob and husk of KND had the highest at maturity stage at KK. In general, corn cob and silk had high DPPH at immaturity stage and seed, cob and husk of KND at KK had high DPPH at maturity stage. However, cob and silk had the highest TEAC at immaturity stage and cob and husk especially KND had high TEAC at maturity stage. This information is useful for use waxy corn as food, food supplement and functional food products for corn consumers and food industry