title: Chemical constituents of Swertia longifolia Boiss. with α-amylase inhibitory activity.
abstract: α-Amylase inhibitors play a critical role in the control of diabetes and many of medicinal plants have been found to act as α-amylase inhibitors. Swertia genus, belonging to the family Gentianaceae, comprises different species most of which have been used in traditional medicine of several cultures as antidiabetic, anti-pyretic, analgesic, liver and gastrointestinal tonic. Swertia longifolia Boiss. is the only species of Swertia growing in Iran. In the present investigation, phytochemical study of S. longifolia was performed and α-amylase inhibitory effects of the plant fractions and purified compounds were determined. Aerial parts of the plant were extracted with hexane, chloroform, methanol and water, respectively. The components of the hexane and chloroform fractions were isolated by different chromatographic methods and their structures were determined by (1)H NMR and (13)C NMR data. α-Amylase inhibitory activity was determined by a colorimetric assay using 3,5-dinitro salysilic acid. During phytochemical examination, α-amyrin, β-amyrin and β-sitosterol were purified from the hexane fraction, while ursolic acid, daucosterol and swertiamarin were isolated from chloroform fraction. The results of the biochemical assay revealed α-amylase inhibitory activity of hexane, chloroform, methanol and water fractions, of which the chloroform and methanol fractions were more potent (IC50 16.8 and 18.1 mg/ml, respectively). Among examined compounds, daucosterol was found to be the most potent α-amylase inhibitor (57.5% in concentration 10 mg/ml). With regard to α-amylase inhibitory effects of the plant extracts, purified constituents, and antidiabetic application of the species of Swertia genus in traditional medicine of different countries, S. longifolia seems more appropriate species for further mechanistic antidiabetic evaluations.
authors.affiliation: Medicinal Plants Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, I.R. Iran.
authors.forename: Soodabeh
authors.initials: S
authors.lastname: Saeidnia
authors.affiliation: Traditional Medicine and Materia Medica Research Center and Department of Traditional Pharmacy, School of Traditional Medicine, Shahid Beheshti University of Medical Sciences, Tehran, I.R. Iran; Payame Noor University, Mazandaran, I.R. Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Ara
authors.affiliation: Traditional Medicine and Materia Medica Research Center and Department of Traditional Pharmacy, School of Traditional Medicine, Shahid Beheshti University of Medical Sciences, Tehran, I.R. Iran.
authors.forename: Homa
authors.initials: H
authors.lastname: Hajimehdipoor
authors.affiliation: School of Chemistry, University of New South Wales, UNSW Sydney, 2052 NSW, Australia.
authors.forename: Roger W
authors.initials: RW
authors.lastname: Read
authors.affiliation: Payame Noor University, Mazandaran, I.R. Iran.
authors.forename: Sattar
authors.initials: S
authors.lastname: Arshadi
authors.affiliation: Medicinal Plants Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, I.R. Iran.
authors.forename: Marjan
authors.initials: M
authors.lastname: Nikan
keywords: Amyrin; Daucosterol; Swertia longifolia; Swertiamarin; Ursolic acid; α-Amylase inhibition