Phytochemical and biological studies on Acanthus hirsutus Boiss

Abstract

Acanthus L. is a genus of 30 species of flowering plants in the family Acanthaceae and represented by five species in Turkish flora [1]. Some of the Acanthus species are used as a herbal remedy for various ailments such as cough, chest pain, snake bite, paralysis, asthma, stomach upset, urinary disorders and rheumatic pains in different countries [2, 3]. The titled plant, Acanthus hirsutus Boiss. is endemic for Turkey and used as expectorant, for wound healing and against constipation in Anatolia [4]. There is no phytochemical or biological record in the literature for this species up to now. After serial chromatographies of the methanol extract of the plant, three lignan glucosides (-)-syringaresinol-di-O-β-D-glucopyranoside, (-)-medioresinol-di-O- β -D-glucopyranoside, (-)-pinoresinol-4'-O- β -D-glucopyranoside), two benzoxazinoids (4-hydroxy-2H-1,4-benzoxazin-3(4H)-one, (2R)-2-O- β -D-glucopyranosyl-4-hydroxy-2H-1,4-benzoxazin-3(4H)-one), four phenylethanoid glycosides (acteoside, martynoside, leucosceptoside A, hattushoside) and two phenylpropanoid glucosides (sinapyl aldehyde-4-O- β -D-glucopyranoside, sinapyl alcohol-4-O- β -D-glucopyranoside) were isolated. Aqueous A. hirsutus extract (IC50=201–700µg/ml) and its isolated compounds (IC50=11.17–262.42µg/ml) showed significant cytotoxic activity in vitro against Hep-2, RD and L20B cell lines in MTT assay. Their radical scavenging activities were also found against 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical (IC50=86.30µg/ml for the extract, IC50=10–200µg/ml for the compouds.