| Abstract
| - Selenium fertilizer was foliar applied to determine the effects of antioxidant activity of selenium-enriched rice assessed by α,α-diphenyl-β-picylhydrazyl (DPPH) radical scavenging and the ferricthiocyanate (FTC) method. Results showed that selenium concentration in rice was significantlyenhanced dose dependently. Aqueous or ethanolic extracts of rice displayed significantly higherantioxidant activity against lipid peroxidation. The activities of aqueous extracts were significantlyhigher than those of ethanolic extracts and increased with the increasing selenium concentration inrice. The DPPH assay showed that the kinetic behaviors of aqueous extracts were complex andslow, while ethanolic extracts reacted quickly with DPPH radical. Aqueous extracts of rice exhibitedhigher antiradical efficiencies than ethanolic extracts, and rice (1.275 mg Se kg-1) presented thelowest EC50 values of 533.46 ± 0.58 μg mL-1. As compared to rice extracts, all of the referenceantioxidants showed more than 4-fold antiradical efficiencies than rice extracts. This radical scavengingactivity was significantly correlated with selenium concentrations in rice (R = 0.862, p< 0.05), whileethanolic extracts were inversely correlated with selenium concentration in rice. Keywords: Selenium; extracts of Se-enriched rice; antioxidant activity
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