Upgrading collagenous smooth hound by-products: Effect of hydrolysis conditions, in vitro gastrointestinal digestion and encapsulation on bioactive properties

Collagenous by-products derived from smooth hound (Mustelus mustelus) were studied using trypsin hydrolysis to obtain protein hydrolysates with ACE (angiotensin converting enzyme) and/or PEP (prolyl endopeptidase)-inhibitory activities. Most of the hydrolysates were mainly composed of short peptides...

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Detalles Bibliográficos
Autores: Lajmi, Khouloud, Gómez Estaca, Joaquín, Hammamia, Mohamed, Martínez Álvarez, Óscar
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/178379
Acceso en línea:http://hdl.handle.net/10261/178379
Access Level:acceso abierto
Palabra clave:Protein Hydrolysates
Prolyl endopeptidase-inhibitory activity
ACE-inhibitory activity
Response surface methodology
Trypsin
Encapsulation
Descripción
Sumario:Collagenous by-products derived from smooth hound (Mustelus mustelus) were studied using trypsin hydrolysis to obtain protein hydrolysates with ACE (angiotensin converting enzyme) and/or PEP (prolyl endopeptidase)-inhibitory activities. Most of the hydrolysates were mainly composed of short peptides. A response surface methodology (RSM) was used to optimize the conditions of hydrolysis (pH 7, 8 or 9, and temperatures of 35, 45 or 55ºC), which led to a higher degree of hydrolysis (DH=3.4%), as well as to an increase in ACE and PEP-inhibitory activities (maximal inhibitions of 68.1 and 81.7%, respectively). According to the model used, neither hydrolysis temperature nor pH in the ranges studied had a significant effect on DH, whereas PEP-inhibitory activity was significantly affected by both factors. pH had a significant effect on ACE-inhibitory activity. Optimum conditions of hydrolysis to obtain maximum activity differed for the two activities: 35ºC/pH 7 for PEP-inhibitory activity and 45.9ºC/pH 9 for ACE-inhibitory activity. The results suggested that these biological activities were influenced by peptide sequence rather than peptide length. This was also confirmed by the amino acid composition and molecular weight (MW) profiles. The ACE-inhibitory activity of the most potent hydrolysate was evaluated after in vitro gastrointestinal digestion. The results showed a worsening of the activity, which was related to small peptide losses and to the appearance of new low MW peptides.Hydrolysate encapsulation using an alginate-whey protein isolate microsphere improved the ACE-inhibitory activity (IC50=0.24 mg/ml).