[Polyphenol content and antioxidant activity of several seeds and nuts]

Abstract

Foods from plant origin not only provide human diet with certain antioxidant vitamins (C, E and beta-carotene), but also a complex mixture of polyphenols, with antioxidant activity. Numerous studies have been focused on the protective and preventing effect of this antioxidant activity on certain degenerative illnesses such as cardiovascular, cancer, and neurological diseases, cataracts and oxidative stress dysfunctions. The objective of this work was to evaluate total polyphenol content and antioxidant activity of several seeds, nuts, or grains such as Theobroma cacao, Canpsiandra comosa Benth (chiga), Sorghum bicolor, L. Moench, Melicoccus bijugatus (genip). Total polyphenol content was assessed by the Folin-Ciocalteau method and the antioxidant activity by the beta carotene/linoleate, reducing power, and the anti-radical activity methods. Results showed genip pericarp with the lowest polyphenol content (1.40 gGAE/100 g), and cacao beans with the highest (6.66 gGAE/100 g). Reducing power of cacao beans was also the highest and similar to the reducing power of 5.80 g ascorbic acid/100 g, followed by Campsiandra comosa. Moreover, Campsiandra comosa and cacao seeds presented an antioxidant activity comparable to that of the butylhydroxianisol, a synthetic antioxidant. The highest anti-radical activity was shown by Campsiandra comosa with an EC50 of 2.67 g/gDPPH. Total polyphenol content shows a good correlation with the antioxidant activity. Moreover, these seeds might have the same health beneficial effects attributed to other fruits and vegetables.