Identification and characterization of antioxidant peptides obtained by gastrointestinal digestion of amaranth proteins

ORSINI DELGADO, M. C.; NARDO, AGUSTINA; PAVLOVIC, MARIJA; TIRONI, V.A.

FOOD CHEMISTRY

ELSEVIER SCI LTD

Año: 2016 vol. 197 p. 1160 - 1167

0308-8146

The objective of the present work was to separate and identify antioxidant peptides from a simulated gastrointestinaldigest (Id) from Amaranthus mantegazzianus proteins (I), which has previously been demonstratedto have this activity. I and Id were separated by preparative RP-HPLC. Fractions were evaluated bythe ORAC method and the more active ones were analyzed by LC?MS/MS. Each fraction presented diversepeptides from different proteins, most of them from the 11S globulin. After grouping the peptides from 11Sglobulin according to their overlapping sequences, and based on previous information about structure?activity relationships, ten sequences were synthesized, in order to evaluate their antioxidant activity.Four peptides presented interesting activity: AWEEREQGSR > YLAGKPQQEH IYIEQGNGITGM TEVWDSNEQ. They exhibited some of the structural characteristics already known to demonstrate thisactivity, all of them containing at least one bulky aromatic residue. All belonged to little structured, internalor exposed regions of the acid subunit of the 11S globulin