Stability to gastrointestinal enzymes and structure–activity relationship of β-casein-peptides with antihypertensive properties

Physiological digestion plays a key role in the formation and degradation of angiotensin-converting enzyme (ACE)-inhibitory peptides. In this study, we evaluated the impact of a simulated gastrointestinal digestion on the stability of eight peptides previously identified in fermented milk with antih...

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Detalles Bibliográficos
Autores: Quirós, Ana, Contreras-Gámez, María Mar, Ramos-González, Mercedes, Amigo, Lourdes, Recio, Isidra
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2009
País:España
Institución:Universidad de Jaén
Repositorio:RUJA. Repositorio Institucional de la Producción Científica de la Universidad de Jaén
OAI Identifier:oai:ruja.ujaen.es:10953/4504
Acceso en línea:https://doi.org/10.1016/j.peptides.2009.06.031
https://www.sciencedirect.com/science/article/pii/S0196978109002745
https://hdl.handle.net/10953/4504
Access Level:acceso abierto
Palabra clave:ACE-inhibitory peptides
Fermented milk
Simulated gastrointestinal digestion
Antihypertensive activity
Competitive inhibitors
Descripción
Sumario:Physiological digestion plays a key role in the formation and degradation of angiotensin-converting enzyme (ACE)-inhibitory peptides. In this study, we evaluated the impact of a simulated gastrointestinal digestion on the stability of eight peptides previously identified in fermented milk with antihypertensive activity. Two of these identified peptides with sequences LHLPLP and LVYPFPGPIPNSLPQNIPP, possess ACE-inhibitory activity in vitro and antihypertensive activity in vivo. The results showed that LHLPLP was resistant to digestive enzymes. In contrast, LVYPFPGPIPNSLPQNIPP was totally hydrolyzed and its activity decreased after incubation with pepsin and a pancreatic extract. The peptide LHLPLP was incubated with ACE and was found to be a true inhibitor of the enzyme and to exhibit a competitive inhibitor pattern. A structure–activity relationship study of this peptide was carried out by synthesizing several modified peptides related to the sequence LHLPLP. The substitution of amino acid Leu in the penultimate position by Gly improved the ACE-inhibitory activity twofold and the substitution of Pro at C-terminal position by Arg increased the activity twofold, with an IC50 of LHLPLR as low as 1.8 μM.