CHANGES IN NON-ENZYMATIC ANTIOXIDANT CAPACITY AND LIPID PEROXIDATION DURING GERMINATION OF WHITE, YELLOW AND PURPLE MAIZE SEEDS

Abstract

In this study, the changes in non-enzymatic antioxidant capacity and lipid peroxidation during the germination process of purple, yellow and white maize seeds were compared, under favorable conditions. Results showed that germination can increase non-enzymatic antioxidant capacity (evaluated with ferric reducing power and 2, 2-diphenyl-1-picryl-hydrazylhydrate radical scavenging capacity) and lipid peroxidation levels for all these seeds. In addition, non-enzymatic antioxidant capacity observed in the germinating seeds were in the order of purple > yellow > white. However, the highest and lowest levels of lipid peroxidation could be seen during the germination processes of the white and purple seeds, respectively. In addition, the germination rates of the seeds followed the order of white > yellow > purple. Further studies showed that H2O2 treatment can significantly promote seed germination, especially for purple seeds. In addition, DMTU (dimethylthiourea), a specific scavenger for H2O2, could slightly but significantly arrest dormancy release. Data analysis showed that a high negative correlation (R2 = －0.955) existed between non-enzymatic antioxidant capacity and germination rates. However, a high positive correlation (R2 = 0.860) could be detected between lipid peroxidation and germination rates. Finally, lipid peroxidation as a possible novel signaling mechanism for seed germination has been discussed under stress-free conditions.