Antioxidant activities of extracts and subfractions from Inonotus Obliquus

The ethanolic crude extracts and three subfractions (ethyl acetate fraction, n-butanol fraction, and aqueous fraction) from Inonotus Obliquus were obtained by sequential partitioning and their antioxidant activities were investigated in the present study. The methods of the total antioxidant capacity measured by the ferric-reducing antioxidant power assay, reducing power assay, scavenging activities towards DPPH, superoxide anion and hydroxyl radical employed in this study were established in in vitro systems. The amounts of total phenolics and total flavonoids were also determined by spectrophotometer. The results showed that the crude extracts and subfractions exhibited antioxidant activities in different evaluating system. The decreasing order of antioxidant activities is ethyl acetate fraction >n-butanol fraction >crude extract>aqueous fraction. A similar order of the amounts of phenolics and flavonoids in extract and subfractions was found. The results showed that the extent of antioxidant activities is in accordance with the amounts of phenolics and flavonoids existing in extracts and subfractions.