Antioxidant Capacity of Caffeic Acid, Phloretin and Glutathione Mixtures and Formula Optimization

In this paper, the synergistic antioxidant effect of caffeic acid, phloretion and glutathione was studied.Three different models, 2,2diphenyl-1-picrylhydrazyl (DPPH), reducing power and Trolox equivalent antioxidant capacity, were used to evaluate the antioxidant capacity of the antioxidants and their combinations.According to the results, not only formula with different proportions of antioxidants showed different synergistic effects in the same model, but also the same formula showed different synergistic effects in different models.By considering the antioxidation mechanism, it found that the antioxidant synergism effect which could enhance the antioxidant effectiveness of natural antioxidants was attributed to the regeneration of the different antioxidants.Principal component analysis combined with response surface methodology (PCA-RSM), overall desirability combined with response surface methodology (OD-RSM) and full probability evaluation combined with response surface methodology (FPE-RSM) methods were used to optimize formula, respectively.From the results of FPE-RSM method, the optimal formula contains caffeic acid 47.8 %, phloretin 29.6 % and glutathione 22.6 %.Our research will help to select the optimal formula and make advanced antioxidant additives cosmetic system.