Antioxidant activity of Swietenia macrophylla king bark extracts

This study investigated the antioxidant activity from the methanol (MeOH) soluble extract of the inner and outer bark of Swietenia macrophylla. The MeOH soluble extracts were fractionated into ethyl acetate (EtOAc) soluble and insoluble. The antioxidant activity was conducted by DPPH (1,1-diphenyl-2-picrylhydrazyl) method and the phenolic compounds were detected by GC-MS. The levels of total phenolic content of soluble and insoluble fraction of EtOAc of outer bark were higher than in inner bark, while total flavonoid content showed opposite results. The crude methanol extract and its EtOAc soluble fraction of outer bark showed a higher level of antioxidant activity. The GC-MS analysis detected higher levels of fatty acids and alcohols of 87.12% than phenolic compounds of 12.17% in the inner bark, while the outer bark showed the opposite pattern with phenolic compounds of 82.65% than fatty acids of 8.43%. A strong correlation was demonstrated between total phenolic content and antioxidant activity.