Recovery of casein-derived peptides with in vitro inhibitory activity of angiotensin converting enzyme (ACE) using aqueous two-phase systems

Evaldo Cardozo de Souza Jr; Jane Sélia Dos Reis Coimbra; Eduardo Basílio de Oliveira; Renata Cristina Ferreira Bonomo

doi:10.1016/j.jchromb.2014.10.014

Recovery of casein-derived peptides with in vitro inhibitory activity of angiotensin converting enzyme (ACE) using aqueous two-phase systems

J Chromatogr B Analyt Technol Biomed Life Sci. 2014 Dec 15:973C:84-88. doi: 10.1016/j.jchromb.2014.10.014. Epub 2014 Oct 22.

Authors

Evaldo Cardozo de Souza Jr¹, Jane Sélia Dos Reis Coimbra², Eduardo Basílio de Oliveira³, Renata Cristina Ferreira Bonomo¹

Affiliations

¹ Departamento de Tecnologia Rural e Animal, Universidade Estadual do Sudoeste da Bahia, Praça Primavera 40, Bairro Primavera, 45700-000 Itapetinga, BA, Brazil.
² Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa, Campus Universitário s/n, Centro, 36570-900 Viçosa, MG, Brazil. Electronic address: jcoimbra@ufv.br.
³ Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa, Campus Universitário s/n, Centro, 36570-900 Viçosa, MG, Brazil.

PMID: 25464099
DOI: 10.1016/j.jchromb.2014.10.014

Abstract

Peptides inhibiting the activity of angiotensin converting enzyme (ACE) were obtained by trypsin-catalyzed hydrolysis of bovine milk casein, performed at 37°C, during 1, 2, 5, 8 and 24h. Results of in vitro inhibitory activity ranged between 13.4% and 78.5%. The highest ACE inhibitory activity was evidenced for hydrolysates obtained after 2h of reaction. Aqueous two-phase systems (ATPS) formed by polyethylene glycol of 1500gmol^-1 (PEG 1500)+sodium phosphate or potassium phosphates were produced and evaluated, in terms of partition coefficients (K) and extraction yields (y), to recovery the casein hydrolysates at room temperature. In ATPS containing sodium phosphate, the peptides showed a slightly greater affinity toward the bottom salt-rich phase (0.1≤K≤0.9; 5.7%≤y≤47%). In the case of ATPS containing potassium phosphates, these molecules showed substantially greater affinity toward the top polymer-rich phase (137≤K≤266; y≥99%). These results point out extraction using PEG 1500/potassium phosphate ATPS is an efficient technique to recover casein hydrolysates containing ACE inhibitors peptides. Outlined data will be helpful in integrating such unit operation to larger scale processes.

Keywords: Antihypertensive; Bioseparation; Bovine milk; Phase equilibrium; Protein; Trypsin.