ABTS radical cation scavenging ability of rice bran was measured according to the method of Arts and others (2004). A 30 μL sample was mixed with 3 mL ABTS radical cation solution, and then left to stand in dark place for 7 min at room temperature. The absorbance was measured at 734 nm using spectrophotometer and BHT was used for comparison. ABTS radical cation solution was prepared by mixing with 2.45 mM potassium persulfate and 7 mM ABTS stock solution, and then stood in dark place for more than 12 h at room temperature. For analysis, 5 mM phosphate buffered saline (PBS, pH 7.4) was added to 2.45 mM ABTS radical cation solution to make an absorbance of 0.70 ± 0.02 at 734 nm. The scavenging ability was calculated by using the formula: scavenging ability(%) =[(absorbance 734 nm of control − absorbance 734 nm of sample)/absorbance 734 nm of control]×100.