Amaranth peptides from gastrointestinal digestion: antioxidant activity against physiological reactive species.?

ORSINI, MC, GALLEANO, M, AÑÓN, MC Y TIRONI, VA

PLANT FOODS FOR HUMAN NUTRITION

SPRINGER

Lugar: Berlin; Año: 2015 vol. 70 p. 27 - 34

0921-9668

The capacity of simulated gastrointestinal digests from amaranth protein isolate or alcalase-hydrolysate to scavenge diverse relevant reactive species was evaluated. The most active hydrolysate was obtained by gastrointestinal digestion of isolate. A previous treatment of isolate with alcalase and subsequent gastrointestinal digestion did not improve the antioxidant capacity in any of the assays performed, producing a negative effect in some cases. Gastrointestinal digestion produced a strong increment in the scavenging capacity against peroxyl radicals (ORAC assay), hydroxyl radicals (ESR-OH?) and peroxynitrites, decreasing the IC50 values approximately 5, 4 and 5 times, respectively. Metal chelation (HORAC assay) also increased but to a lesser extent (about 2 times). Nitric oxide and superoxide scavenging capacities of digests were not relevant according to the methodologies used. Gastrointestinal digests from amaranth proteins were able to act against reactive species by different mechanisms, showing the protein isolate as a potential functional antioxidant ingredient.