Identification and characterization of antioxidant peptides from chickpea protein hydrolysates

• Chickpea seed proteins have been hydrolyzed with pepsin and pancreatin.
• Several antioxidant peptides have been purified from these hydrolyzates.
• Peptides sequences correspond to legumin fragments, the main chickpea seed protein.
• Most of sequenced peptides contain the antioxidant amino acid histidine.
• Chickpea legumin is an useful source of antioxidant peptides.

Oxidative stress due to the excess of radical oxygen species (ROS) contribute to the development of different diseases. The use of antioxidants may prevent the development of these diseases by counteracting ROS levels. There is an increasing interest in natural antioxidants as they are safer for consumers than synthetic antioxidants. In this work, reducing power, free radical scavenging and cellular antioxidant activities of chickpea peptides fractions have been investigated. Peptide sequences included in fractions with antioxidant activity were identified. Main sequences, ALEPDHR, TETWNPNHPEL, FVPH and SAEHGSLH, corresponded to legumin, the main seed protein. Most peptides contained histidine, which has shown antioxidant activity. Two peptides also included tryptophan and phenylalanine, in which the phenolic group could also serve as hydrogen donor. These results show that legumin is a source of antioxidant peptides of high interest for food and pharmaceutical industries to develop new nutraceuticals and functional foods.