Antioxidant Capacity of Nut and Dried Fruit Combinations Evaluated by Different Methods

Abstract

In order to scientifically evaluate the health benefits of nut and dried fruit combinations, the antioxidant capacity of various combination of nuts with dried fruits was evaluated by chemical extraction method, an in vitro digestion model and a mouse model. The results of the chemical extraction method showed that the nut and dried fruit combinations were rich in nutrients such as polyphenols, fatty acids and proteins, and their capacity to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 2,2’-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation and ferric reducing antioxidant power (FRAP) were significantly enhanced compared to those of the nuts. The in vitro digestion results showed that the phenolic content of the combinations was increased by 2.90%–60.38% and DPPH and ABTS radical cation scavenging capacity by 1.23%–18.60% compared to that of either alone. The best synergistic antioxidant effect was achieved with a 6:4 mixture of nuts and dried fruits. Meanwhile, the combinations of nuts and dried fruits increased the activity of catalase (CAT), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in the serum and liver of mice after gastrointestinal digestion, effectively inhibited the production of malondialdehyde (MDA) and preserved the morphological integrity of mouse hepatocytes. In conclusion, the mixture of nuts and dried fruits has a synergistic antioxidant effect and good antioxidant capacity in vitro and in vivo.

Keywords

• nut and dried fruit combinations; antioxidant activity; phenolic substances; synergistic effect