The scavenging capacity and synergistic effects of lycopene, vitamin E, vitamin C, and beta-carotene mixtures on the DPPH free radical

The biological activity of lycopene can be enhanced by the presence of these other active antioxidants such as beta-carotene, vitamin E, and vitamin C. Since many of these natural antioxidants are consumed together in foods, the potential for synergistic interactions is high in the human diet. The aim of this study was to determine what concentrations and combinations of antioxidants among lycopene, vitamin E, vitamin C, and beta-carotene are capable of producing synergistic antioxidant effects, based on tomato-based food products. Solutions of the scavenging capacities of lycopene, vitamin E, vitamin C, and beta-carotene, alone and in different combinations were measured using the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Three different levels of each antioxidant were used. A comparison of the scavenging capacity (antioxidant activity) of the combinations of antioxidants to the arithmetic sum of the scavenging capacities of the individual antioxidants was used to calculate the synergistic effects (SEs) between the antioxidants. The results showed that the mixture that had the highest SEs (P < 0.01) was the solution combining lycopene (15 mu mol/L), vitamin E (5.0 mu mol/L), vitamin C (0.16 mu mol/L), and beta-carotene (10.83 mu mol/L). The results suggest that the antioxidant property of this combination was substantially superior to the sum of the individual antioxidant effects, and these interactions can enhance the antioxidant effectiveness of natural antioxidants. The results could guide in the formulation and development of functional food products that have high antioxidant potential. Crown Copyright (c) 2007 Published by Elsevier Ltd. on behalf of Swiss Society of Food Science and Technology. All rights reserved.