Phytochemical content and antioxidant properties of colored and non colored varieties of rice bran from Minahasa, North Sulawesi, Indonesia

Two non colored and one colored rice varieties from Minahasa Regency, North Sulawesi, Indonesia were analyzed to determine the phytochemicals and antioxidant properties as natural antioxidant sources. Different brans of rice varieties divided into two groups: red rice and non colored (Superwin and Cigeulis) were macerated by ethanol (70%) and extracted with organic solvents (butanol, ethyl acetate and hexane). Antioxidant properties were determined by means of radical, 1,1-diphenyl-2-picrylhydrazyn (DPPH) assay, total phenol content (TPC), total anthocyanin content, and thiobarbituric acid (TBA) assay. The phytochemical analysis indicated rice bran crude extracts contained phenolic, flavonoid, alkaloid, triterpenoid, steroid and saponin compounds. Red variety had the highest DPPH scavenging radical activity (88.29 ± 5.62%), with the lowest IC50 value (26.26 ± 0.95 μg/ml) and highest total anthocyanin content (68.61 ± 1.98 mg/g). The colored varieties had better antioxidant properties than non colored varieties. It can be concluded that colored varieties could be used as a natural antioxidant source.