Antioxidant Activity of Various Fractions of Non-Tannin Phenolics of Canola Hulls

Publisher Website
Google Scholar
Abstract
Cyclone canola hulls were extracted with 70% (v/v) acetone. The dried crude extract was dissolved in ethanol and fractionated on a Sephadex LH-20 column using 95% (v/v) ethanol as the mobile phase. Five major fractions were isolated according to the UV absorption. All fractions exhibited marked antioxidant activity in a β-carotene−linoleate model system. Fractions I and II showed the best preventive effect against the bleaching of β-carotene. The scavenging effect of fractions I, III, and V, at 1 mg, on α,α-diphenyl-β-picrylhydrazyl (DPPH) radical was 67.4%, 80.7%, and 63.3%, respectively. Fractions II and IV showed weak DPPH scavenging effects. The reducing power of phenolics present in fractions IV and V was greater than that of fractions I−III, and the observed data correlated well (r2 = 0.937; P = 0.007) with the total content of phenolics present in each fraction. Keywords: Non-tannin phenolics; canola; hulls; antioxidative properties; reducing power; scavenging activity