Aqueous extracts of ripe red pepper and tomato fruits inhibit Fe2+-induced oxidative stress in rat testes and kidney

Abstract

Objective: Tomatoes (Lycopersicon esculentum Mill) and red pepper fruits (Capsicum annuum L) are important vegetables usually consumed as vegetable foods, as the spice added to food fresh, dried, refined, ground, and as the principal or incidental ingredient in sauces. This study sought to investigate the inhibitory effect of the aqueous extract of ripe tomato and red pepper fruits on Fe2+-induced lipid peroxidation in rat testes and kidney. Methods: The aqueous extract of ripe tomatoes and red pepper were prepared. Then, the total phenolic content and the antioxidant activities of the extracts were evaluated using various spectrophotometric methods. Result: The aqueous extract of tomato had the highest total phenolic, flavonoid and vitamin C contents, as well as 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radical scavenging ability while the Fe2+ chelating ability of the two extracts were almost the same. Furthermore, the two extracts caused a significant decrease in the malondialdehyde contents in testes and kidney with aqueous extract of tomato having the highest inhibitory effect on Fe2+-induced lipid peroxidation. Conclusion: This protective effect of the extracts on Fe2+-induced lipid peroxidation in rat testes and kidney could be attributed to their phenolic compounds and, the possible mechanism may be through their antioxidant activities. Therefore, ripe tomato and red pepper seem to have potential for the management/prevention of Fe2+-induced oxidative stress in the testes and kidney; among both, ripe tomato presented a greater ability than ripe red pepper.