title: Bioguided isolation of angiotensin-converting enzyme inhibitors from the seeds of Plantago asiatica L.
abstract: Ethanolic extract of the seeds of Plantago asiatica L. showed significant inhibitory activity of angiotensin-converting enzyme (ACE) determined by monitoring the transformation from a substrate hippuryl-histidyl-leucine (HHL) to the product hippuric acid (HA) in vitro using an UPLC-MS method. The bioguided fractionation of the extract resulted in the isolation of four ACE inhibitory active phenylpropanoid glycosides acteoside, isoacteoside, plantainoside D, and plantamajoside with IC(50) values of 2.69 mM, 2.46 mM, 2.17 mM, and 2.47 mM, respectively. Their structures were elucidated through the analysis of NMR, UV, IR and MS data. Our study is the first demonstration that Plantago asiatica L. and its major constituents have ACE inhibitory activity in vitro. It is assumed that the identified compounds contribute to the angiotensin-converting enzyme-inhibitory activity of the extract.
authors.affiliation: The MOE Key Laboratory for Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Zhangjiang Hi-Tech Park, Shanghai 201210, PR China.
authors.forename: Fang
authors.initials: F
authors.lastname: Geng
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Guixin
authors.initials: G
authors.lastname: Chou
authors.forename: Zhengtao
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D002396:Catechols / Q000302:isolation & purification / Q000494:pharmacology; D005960:Glucosides / Q000302:isolation & purification / Q000494:pharmacology; D006027:Glycosides / Q000302:isolation & purification* / Q000494:pharmacology; D006626:Hippurates / Q000378:metabolism; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D009842:Oligopeptides / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D010943:Plantago / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D002396:Catechols; D005960:Glucosides; D006027:Glycosides; D006626:Hippurates; D009842:Oligopeptides; D010936:Plant Extracts; C421173:plantamajoside; C010980:hippuryl-histidyl-leucine; C030514:hippuric acid