Isolation of active constituents from cherry laurel (Laurocerasus officinalis Roem.) leaves through bioassay-guided procedures

Ethnopharmacological relevance: The fresh leaves of Laurocerasus officinalis Roem. (Rosaceae) are externally used against pain and feverish symptoms in Turkish folk medicine. Aim of the study: Effects of the extracts, fractions and isolated compounds from the leaves of L officinalis were investigated using in vivo models of inflammation and pain in mice. Methods: The crude ethanolic extract from the leaves of plant was sequentially fractionated into five subextracts; explicitly, n-hexane, chloroform, ethyl acetate (EtOAc), n-butanol, and remaining water extracts. Further studies were carried out on the most active EtOAc subextract was further subjected to fractionation through column chromatography. For the anti-inflammatory activity, carrageenan-induced hind paw edema and acetic acid-induced increase in capillary permeability models, and for the antinociceptive activity p-benzoquinone-induced writhing test in mice were employed. Results: Ethanolic extract of the leaves was shown to possess significant inhibitory activity in the assay methods without inducing any gastric damage. Through bioassay-guided fractionation and isolation procedures three phenolic compounds, 2-O-beta-D-glucopyranosyl-2-hydroxyphenyl-acetic acid (1), kaempferol-3-O-beta-D-xylopyranosyl-(1 -> 2)-O-beta-D-glucopyranoside (2) and (+)-catechin (3) were isolated from the active fraction and their structures were elucidated by spectral techniques (1D and 2D NMR, ESIMS). Conclusion: The experimental data verified that Laurocerasus officinalis leaves displayed remarkable anti-inflammatory and antinociceptive activity. (C) 2011 Elsevier Ireland Ltd. All rights reserved.