Studying On Individual Antioxidant Activities And Synergistic Effects For Seven Antioxidants

On the base of reviewing research of antioxidants, we first evaluated the individual and the combined antioxidant activities for seven commonly used antioxidants-BHT.TBHQ.VC.VE.TP.Citric acid and Phytic acid by two methods-DPPH- and TBARS. In addition, we analyzed the synergistic effects by three ways-Addition Methodology, Direct Comparison Methodology and Response Surface Methodology.- Comparing the individual antioxidant activities for seven antioxidants was carried out by DPPH- method and TBARS method.1. Scavenging effects on free radical of seven antioxidants by DPPH-method were ranked: TBHQ > TP > VC > VE > BHT > Citric acid > Phytic acid. Antioxidant activity was positive correlated to the number of phenolic hydroxyl groups and the stability of newly formed free radical.2. Inhibition effects on linoleic acid lipid pro-oxidation of seven antioxidants by TBARS method were ranked: BHT > VE > TBHQ > TP> Citric acid. Phytic acid and VC accelerated the lipid pro-oxidation in our experiment. Antioxidant activity was positive correlated to not only the number of phenolic hydroxyl groups and the stability of newly formed free radical but also the solubility and the ability of chelating the lipid pro-oxidative metal traces.3. The antioxidant activity of phenolic compound was stronger than that of metal chelator was obtained in two assays. This maybe caused by the different antioxidant mechanisms.4. The activity orders were different in two assays.Assessing the synergistic effects was carried out by Addition Methodology, Direct Comparison Methodology and Response Surface Methodology.1. The contour map from RSM was very useful for prediction purposes of mixed antioxidants.2. Synergistic effects on nine kinds of mixed antioxidants-TBHQ+VE, TBHQ+BHT, TBHQ+TP, TBHQ + Phytic acid, VE+BHT, VE+TP, VE+ Phytic acid, VE+ Citric acid and TP+ Phytic acid were obtained by DPPH- method.3. Synergistic effects on three kinds of mixed antioxidants-TBHQ + VE, VE + Citric acid and TBHQ + Citric acid were obtained by TBARS method.4. Synergistic effect of mixed antioxidant was influenced by the assays.