Antioxidative and antigenotoxic effects of garlic (Allium sativum L.) prepared by different processing methods

This study describes the antioxidant activities and antigenotoxic effects of garlic extracts prepared by different processing methods. Aged-garlic extract (AGE) showed a significantly higher total phenolic content (562.6 +/- 1.92 mg/100 g garlic acid equivalents) than those of raw garlic extract (RGE) or heated garlic extract (HGE). The SC(50) for DPPH RSA in HGE was significantly the highest at 2.1 mg/ml. The SC(50) for SOD-like activity in garlic extracts was, in decreasing order, RGE (7.3 mg/ml) > AGE (8.5 mg/ml) > HGE (9.2 mg /ml). The ED(50) of AGE was the highest (19.3 microg/ml) regarding H2O2 induced DNA damage and its inhibition rate was 70.8%. The ED(50) of RGE for 4-hydroxynonenal (a lipid peroxidation product) induced DNA damage was 38.6 microg/ml, followed by AGE > HGE. Although the heat treatment of garlic tended to decrease the TPC and SOD-like activity and increased DPPH RSA, garlic, in general, has significant antioxidant activity and protective effects against oxidative DNA damage regardless of processing method.