Reactive oxygen species scavenging, metal chelation, reducing power and lipid peroxidation inhibition properties of different solvent fractions from Hizikia fusiformis

Abstract

The antioxidative properties of different organic and aqueous fractions obtained by solvent fractionation of 80% methanolic extract of Hizikia fusiformis were investigated for free-radical, reactive oxygen species scavenging (O2⋅−, H2O2, HO⋅, NO⋅), metal chelation, reducing power and lipid peroxidation (conjugated diene and thiobarbituric acid reactive substances formation) inhibition assays. Of the organic and aqueous fractions tested, the organic ethyl acetate and aqueous chloroform fractions were notably effective. Almost all fractions exhibited significantly higher activities on NO⋅ and 1,1-diphenyl-2-picrylhydrazyl scavenging compared with commercial antioxidants. The organic chloroform fraction showed the highest HO⋅ scavenging activity among other counterparts. The aqueous chloroform fraction demonstrated O2⋅− scavenging and metal chelating activities that are similar to those of butylated hydroxytoluene. The lipid peroxidation inhibition was significantly higher in the organic ethyl acetate fraction than that of α-tocopherol. These data suggest that both organic and aqueous fractions are rich in hydrophobic and hydrophilic antioxidative compounds with different antioxidative properties.