title: Structure elucidation and inhibitory effects on human platelet aggregation of chlorogenic acid from Wrightia tinctoria.
abstract: BACKGROUND
  Interest in natural compounds as sources of potentially new treatment options is growing rapidly. Preliminary screening of many different plant extracts showed that Wrightia tinctoria acts as a potent human platelet aggregation inhibitor. The aim of the present study was to isolate and characterize the active compound responsible for potent inhibition of human platelet aggregation in vitro.
  
  
  METHODS
  A 70% ethanolic extract derived from W. tinctoria seeds was fractionated with chloroform followed by ethyl acetate. The ethyl acetate fraction was further fractionated and purified through a series of three successive column chromatographic separations using silica gel, Sephadex LH-20, and C-18 columns. Liquid chromatography coupled to negative electrospray ionization tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR) studies were performed in the structure determination of the active phenolic compound present in the ethyl acetate fraction of W. tinctoria seeds.
  
  
  RESULTS
  A phenolic compound has been isolated and identified as chlorogenic acid by LC-MS/MS and NMR studies. Chlorogenic acid showed concentration-dependent inhibitory effect on collagen-induced platelet aggregation in vitro with an IC50 of 0.2363 μg/μl.
  
  
  CONCLUSIONS
  The present data suggest that chlorogenic acid can be developed as potential antiplatelet agent in the treatment of cardiovascular diseases in diabetes mellitus.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy and Health Professions, St. John’s University, Jamaica, NY 11439, USA. ripalamin@gmail.com
authors.forename: Ripal P
authors.initials: RP
authors.lastname: Amin
authors.forename: Naveen
authors.initials: N
authors.lastname: Kunaparaju
authors.forename: Sunil
authors.initials: S
authors.lastname: Kumar
authors.forename: Tony
authors.initials: T
authors.lastname: Taldone
authors.forename: Michael A
authors.initials: MA
authors.lastname: Barletta
authors.forename: S William
authors.initials: SW
authors.lastname: Zito
mesh_terms: D029062:Apocynaceae / Q000737:chemistry*; D002726:Chlorogenic Acid / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D003094:Collagen / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D010936:Plant Extracts; D010975:Platelet Aggregation Inhibitors; D002726:Chlorogenic Acid; D003094:Collagen