Nutritional value, antibacterial activity, ACE and DPP IV inhibitory of red pomegranate seeds protein and peptides.

One of the challenges related to food and agriculture industries is the production of waste and by-products. In this study, red pomegranate seeds (PS) was selected as a by-product (from oil extraction) for the production of bioactive hydrolysate (with Alcalase, pancreatin, trypsin and pepsin). The composition of essential (~ 23.3%), hydrophobic (~ 32.9%), antioxidant (~ 13.9%) amino acids, and PER index (~ 2.1) especially in hydrolysates by alcalase (H-Al) indicated the nutritional value, antioxidant activity and high digestibility of hydrolysate. Secondary structures and amide regions (I, II and III) were identified in PS-protein. Enzymolysis led to the improvement of solubility, emulsification and foaming capacity of PS-protein, especially in acidic conditions. The water and oil holding capacity were also affected by the type of proteases. The most biological activities (DPPH, ABTS, OH, NO radicals scavenging, reducing power, total antioxidant and metal-ions chelating activities), also, Angiotensin I-converting enzyme (ACE) (50.1%) and Dipeptidyl peptidase-4 (DPP-IV) (61.2%) inhibition were achieved through hydrolysis using Alcalase and pancreatin. While, the highest antibacterial effect (E. coli and S. aureus) was obtained after hydrolysis with Alcalase. PS- hydrolysate can be considered as a natural nutritious, functional, antioxidant, preservative, blood pressure lowering and antidiabetic compounds in food formulations and dietary supplements.