Casein hydrolysates by Lactobacillus brevis and Lactococcus lactis proteases: Peptide profile discriminates strain-dependent enzyme specificity

Casein from ovine and bovine milk were hydrolyzed with two extracellular protease preparations from Lactobacillus brevis and Lactococcus lactis. The hydrolysates were analyzed by HPLC–MS/MS for peptide identification. A strain-dependent peptide profile could be observed, regardless of the casein ori...

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Detalles Bibliográficos
Autores: Zohra Bounouala, Fatima, Roudj, Salima, Karam, Nour-Eddine, Recio, Isidra, Miralles, Beatriz
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/194029
Acceso en línea:http://hdl.handle.net/10261/194029
Access Level:acceso abierto
Palabra clave:Lactic acid bacteria
Enzyme specificity
Bioactive peptides
Tandem mass spectrometry
Sheep milk
Casein hydrolysates
Descripción
Sumario:Casein from ovine and bovine milk were hydrolyzed with two extracellular protease preparations from Lactobacillus brevis and Lactococcus lactis. The hydrolysates were analyzed by HPLC–MS/MS for peptide identification. A strain-dependent peptide profile could be observed, regardless of the casein origin, and the specificity of these two proteases could be computationally ascribed. The cleavage pattern yielding phenylalanine, leucine, or tyrosine at C-terminal appeared both at L. lactis and Lb. brevis hydrolysates. However, the cleavage C-terminal to lysine was favored with Lb. brevis protease. The hydrolysates showed ACE-inhibitory activity with IC50 in the 16–70 μg/mL range. Ovine casein hydrolysates yielded greater ACE-inhibitory activity. Previously described antihypertensive and opioid peptides were found in these ovine and bovine casein hydrolysates and prediction of the antihypertensive activity of the sequences based on quantitative structure and activity relationship (QSAR) was performed. This approach might represent a useful classification tool regarding health-related properties prior to further purification.