Feasibility of Electrodialysis with Bipolar Membrane for Regulating the pH of the Reaction During the Hydrolysis of Hemoglobin to Obtain Bioactive Peptides

Bovine cruor, a slaughterhouse waste, is mainly composed of hemoglobin, a protein rich in bioactive peptides, which can be released after hydrolysis by pepsin [1-2]. The aim of this project was to prove the feasibility of enzymatic hydrolysis of bovine hemoglobin by electrodialysis with bipolar membrane (EDBM) to obtain bioactive peptides. Electromembrane processes, recognized as green processes, are amongst the various membrane technologies that are increasingly used in the bio-food and pharmaceutical industries to concentrate, purify or modify molecules or food components [3]. Unlike pressure driven membrane techniques, the migration of the charged compounds and the dissociation of water molecules during the EDBM are induced by an electric potential difference applied between two electrodes [3]. The use of the EDBM for the enzymatic hydrolysis of hemoglobin has allowed the production of hydrolysates containing a low concentration of mineral salts. In fact, the EDBM was used to acidify the hemoglobin solution to the desired pH before its hydrolysis by pepsin without the need to add chemical agents as in classic enzymatic hydrolysis. The hydrolysis enzymatic mechanism during EDBM was a mechanism called 'Zipper' identical to the one obtained in classical hydrolysis (control). The EDBM allowed the generation of bioactive peptides from hemoglobin hydrolysis that have been identified by UPLC-MS. The identified and characterized peptides showed antibacterial, antifungal and antioxidant activity. Indeed, it contained the target peptide, neokyotorphin, which has antimicrobial and antioxidant activities. Therefore, the EDBM is applicable to the transformation of bovine hemoglobin into bioactive peptides containing a low concentration of mineral salts.