Validation of a colorimetric assay for the in vitro screening of inhibitors of angiotensin-converting enzyme (ACE) from plant extracts.

Anew method for the in vitro screening of plant extracts with potential angiotensin-converting enzyme (ACE) inhibitory activity is proposed. The method is based on the cleavage of the substrate hippuryl-glycyl-glycine by ACE and subsequent reaction with trinitrobenzenesulfonic acid to form 2,4,6-tri...

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Detalles Bibliográficos
Autores: Serra, Carla Penido, Côrtes, Steyner de França, Lombardi, Júlio Antônio, Oliveira, Alaíde Braga de, Braga, Fernão Castro
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:Brasil
Institución:Universidade Federal de Ouro Preto (UFOP)
Repositorio:Repositório Institucional da UFOP
Idioma:inglés
OAI Identifier:oai:repositorio.ufop.br:123456789/1215
Acceso en línea:http://www.repositorio.ufop.br/handle/123456789/1215
Access Level:acceso abierto
Palabra clave:In vitro colorimetric assay
Plant extracts
Screening
Angiotensin-converting enzyme inhibitors
Descripción
Sumario:Anew method for the in vitro screening of plant extracts with potential angiotensin-converting enzyme (ACE) inhibitory activity is proposed. The method is based on the cleavage of the substrate hippuryl-glycyl-glycine by ACE and subsequent reaction with trinitrobenzenesulfonic acid to form 2,4,6-trinitrophenyl-glycyl-glycine, whose absorbance is determined at 415nm in a microtitre plate reader. Rabbit lung dehydrated by acetone was employed as an enzyme source. Validation of the method showed satisfactory intra-day (CV ¼ 7.63%) and inter-day precision (CV ¼ 13.61%), recovery (97–102.1%), sensitivity (IC50 ¼ 14.1 nmol/l) and linearity in the range 7.5–120 mmol/l of glycyl-glycine (r2 ¼ 0:9921). Besides, the method showed good correlation with a HPLC assay already established for the screening of ACE inhibitors (r ¼ 0:9935 and 0:9034; respectively, for captopril solutions and for plant extracts). The method involves only inexpensive reagents and apparatus.