In vitro Antioxidant and Free Radical Scavenging Activity of Diospyros lotus and Pyrus boissieriana growing in Iran

Current research into free radicals has confirmed that foods rich in antioxidants play an essential role in the prevention of many diseases. The potential antioxidant activities of Diospyros lotus and Pyrus boissieriana fruits investigated employing six in vitro assay systems. IC50 for DPPH radical-scavenging activity was 1.45 ± 0.03 for D. lotus and 3.0 ± 0.04 mg ml-1 for P. boissieriana, respectively. The extracts showed weak nitric oxide-scavenging and Fe2+ chelating ability activity. The D. lotus extracts was better than P. boissieriana. The peroxidation inhibition of D. lotus and P. boissieriana extracts exhibited values from 89 (at 24th) to 94% (at 72nd hrs) and 91 to 95% respectively. Neither of them showed good scavenging activity of H2O2. The total amount of phenolic compounds in each extracts was determined as gallic acid equivalents and total flavonoid contents were calculated as quercetin equivalents from a calibration curve. Both of them had high total phenolic and flavonoid contents.