Nutrient Composition and Antioxidant Activity of Zinc- and Selenium-enriched Peanut Sprouts

Abstract:

Despite being indispensable, zinc and selenium are often severely deficient trace elements in humans. To achieve optimal zinc and selenium supplementation for deficient populations, dietary supplements of these elements can be investigated by harnessing the nutrient-absorbing properties of germinating peanuts. In the present study, peanut was used as a carrier of dietary supplements, with zinc sulfate (0, 10, 20, 30, 40, 50 mg•L-1) and sodium selenite (0, 100, 200, 300, 400, 500 mg•L-1) solutions added during seed soaking to attain zinc and selenium enrichment through germination. The results showed that the enrichment of zinc and selenium in peanut sprouts was highest at exogenous zinc and selenium concentrations of 40 and 420 mg•L-1, respectively, with contents being higher than 2.0 and 23.76 times than those in the control peanut sprouts, respectively. Zinc and selenium enrichment also increased the polyphenol content of peanut sprouts. The contents of catechin, salicylic acid, quercetin, and rutin were significantly increased (P<0.05), while that of toxic gossypol was significantly decreased (P<0.05). The significant increases in polyphenol and selenium contents (P<0.05) also enhanced the antioxidant capacity of peanut sprouts. The findings of this study suggest zinc- and selenium-enriched peanut sprouts as a novel zinc-selenium dietary supplement for daily supplementation in zinc- and selenium-deficient populations, providing additional bioactive substances for the human body.