Antioxidant capacity and bioactive compounds of maize silk from different ZP genotypes for application in health-promoting dietary supplements

Abstract

Natural plant-based products have recently been growing in popularity in pharmaceutical and functional food industries due to their antioxidant properties. For centuries, maize silk (Stigma maydis) has been utilized in traditional medicine for the prevention and treatment of numerous medical conditions. The therapeutic, anti-inflammatory, antimicrobial, diuretic, antidiabetic, and antioxidant properties originate from silk's chemical composition, rich in polyphenols, polysaccharides, protein, fiber, alkaloids, vitamins and minerals. Maize silk of five ZP maize genotypes (ZP 355su, ZP 6119k, ZP 5550, ZP 666 and ZP 6263) harvested at three different maturity stages, i.e., days of silking (DS), was used to identify the most promising raw material for the production of health-promoting dietary supplements. The study focused on investigating the contents of bioactive compounds and antioxidant capacity of maize silk. Antioxidant capacity was evaluated after following ABTS+, DPPH•, IC50, and FRAP methodologies for comparison. The genotype ZP 5550 (15 DS) exhibited the highest antioxidant potential. The most abundant bioactive compounds were free phenolic. Notably, genotype ZP 5550 (DS 15), has a significantly higher concentration of total free phenolics, approximately six time higher then those observed in genotype 6119k (15 DS). The total protein content ranged from 12.02% in genotype ZP 6263 (15 DS) to 19.43% in genotype ZP 6119k (7 DS). The findings of this study may have significant implications for maize breeding initiatives and the identification of the most promising hybrids for the manufacturing of functional foods and nutritional supplements