Antioxidant interactions in green tea and oak extracts combination

The aim of present study was to compare antioxidant properties and investigate the possibility of synergism or antagonism interaction between green tea and oak extracts. Green tea extract in all concentrations had a significant (p<0. 05) higher effect than BHT in DPPH free radical scavenging assay and total antioxidant capacity، and in two concentration in reducing power، and in all of the assays was better than oak extract; While only in DPPH free radical scavenging assay the oak extract was better than BHT. Among different combinations of these two extracts، synergism was found in three combination according to DPPH free radical scavenging assay، four combination in total antioxidant capacity assay and all combination in reducing power assay. In the peroxide value assay، the chosen combination showed antagonism، although it was significantly (p<0. 05) more effective than BHT in soy bean oil stability. The result shows that it is possible to use these natural antioxidant as substitute of synthetic antioxidant BHT.