Changes in phytochemical profiles, relevant enzyme activity and antioxidant capacity of different germinated maize varieties

Six typical Chinese maize varieties (Hetian4, Zhengdan958, Yinongyu10, Demeiya1, Dahua1146, Suyu29) have been investigated for carotenoid content, total phenolic content (TPC), antioxidant enzyme activity, and antioxidant capacity during germination. Results showed that the content of the main phytochemicals in germinated maize was higher than that in raw seeds. Hetian4 had the highest total carotenoid content, Zhengdan958 had the highest TPC, and Dahua1146 had the weakest antioxidant capacity after 3-d germination. Zhengdan958 had the highest transcript levels of ZmPSY and ZmLCYE on the 3-day of maize germination. In addition, correlation analysis revealed that the scavenging of oxygen free radical capacity of germinated maize depends on the accumulation of carotenoids, TPC, and antioxidant enzymes. Moreover, the key genes in the carotenoid biosynthetic pathway are closely related to different accumulation of carotenoids. Principal component analysis underlined the effect of the germination, the antioxidant activity, and the carotenoid on the nutritional properties of maize.