RESUMEN
Swertia species are widespread in Eastern and Southern Asian countries and used in traditional medicine as anti-pyretic, analgesic, gastro and liver tonic. Among different species, only Swertia longifolia grows in Iran. In this investigation, antioxidant, cytotoxic and acetylcholinesterase inhibitory activities of S. longifolia have been studied. Aerial parts and roots of the plant were collected, dried and extracted with methanol 80% (total extract). Different extracts of the plant were obtained using hexane, chloroform, ethyl acetate, methanol, methanol:water (1:1) and water, respectively. Cytotoxic activity was determined by MTT assay on MDBK, HepG2, MCF7, HT29 and A549 cell lines. Antioxidant activity was measured by 2,2-diphenyl-1-picryl hydrazyl (DPPH) free radicals and acetylcholinesterase inhibitory (AChEI) effect was evaluated based on Ellman's method in 96-well microplates.The results showed no cytotoxicity of the plant extracts on MDBK, HepG2, MCF7, HT29 and A549 cell lines up to 100 µg/ml. All samples showed radical scavenging activity but methanol extract of aerial parts and ethyl acetate extract of the roots showed the highest effects.Total extract of the roots showed higher AChEI activity than the aerial parts. Among different extracts, chloroform and ethyl acetate extracts of the roots and chloroform and methanol:water extracts of the aerial parts were more potent in AChEI assay. It is concluded that aerial parts and roots of the plant are rich in antioxidant agents with no cytotoxicity on selected cell lines up to 100 µg/ml. Moreover, since antioxidant and AChEI activity of compounds play an important role in the treatment of Alzheimer's disorder, this plant might be a potential candidate for isolation of antioxidant and AChEI compounds which could be used as supportive treatment of Alzheimer's disease.
RESUMEN
Thymus vulgaris L. (Lamiaceae) is a well-known medicinal plant that contains important compounds such as thymol and carvacrol and it has been used in many pharmaceutical dosage forms. Thymol and carvacrol in essential oils are often quantified by gas chromatography (GC) technique but in this work, a validated and reliable high performance liquid chromatography (HPLC) method has been developed for the analysis of these two components in T. vulgaris essential oil. The essential oil of the plant was analyzed by HPLC and GC techniques. The HPLC system consisted of ACE C(18) column and an isocratic acetonitrile:water (50:50) as the mobile phase which was kept at a flow rate of 1 ml/min. The method was validated for selectivity, linearity (r(2) > 0.997 for both thymol and carvacrol), precision (intra-day 0.8-1.9, 1.7-2.6; and inter-day 3.5-4.5, 3.6-4.7) and recovery (97.7%, 97.6%) for thymol and carvacrol, respectively. The limits of detection (LODs) and limits of quantization (LOQs) were calculated to be 2.8, 0.6 µg/ml and 8.6, 1.8 µg/ml for thymol and carvacrol, respectively. The GC system consisted of flame ionization detector (FID) and CP-SIL 8 column. The concentrations of thymol and carvacrol in essential oil obtained by HPLC (41.2%, 4.3%) and GC (40.7%, 4.2%) were compared by statistical methods and they showed good agreement.
RESUMEN
Swertia spp. (Gentianaceae) grow widely in the eastern and southern Asian countries and are used as traditional medicine for gastrointestinal disorders. Swerchirin, one of the xanthones in Swertia spp., has many pharmacological properties, such as, antimalarial, antihepatotoxic, and hypoglycemic effects. Because of the pharmacological importance of Swerchirin in this investigation, it was purified from Swertia longifolia Boiss. as one of the main components and quantified by means of a validated high performance liquid chromatography (HPLC) technique. Aerial parts of the plant were extracted with acetone 80%. Phenolic and non-phenolic constituents of the extract were separated from each other during several processes. The phenolic fraction was injected into the semi-preparative HPLC system, which consisted of a C(18) column and a gradient methanol: 0.1% formic acid mode. Using this method, we were able to purify six xanthones from the plant, in order to use them as standard materials. The analytical method was validated for Swerchirin as one of the most important components of the plant, with more pharmacological activities according to the validation parameters, such as, selectivity, linearity (r(2) > 0.9998), precision (
RESUMEN
In the present study, the dopaminergic receptor agonist apomorphine (0.1, 0.25 and 0.5 mg/kg) induced a dose-dependent licking in rats. Nicotine administration (0.025-250 microg/kg) altered the apomorphine-induced licking. The lower doses of nicotine (0.05 and 0.5 microg/kg) increased while the higher dose of the drug (250 microg/kg) reduced the apomorphine response. The antimuscarinic drug atropine (2.5 and 5 mg/kg) reduced the effects of apomorphine or nicotine plus apomorphine. The central nicotinic receptor antagonist mecamylamine (0.05, 0.25 and 0.5 mg/kg) also reduced the response induced by apomorphine or nicotine plus apomorphine. However, the peripheral nicotinic receptor antagonist hexamethonium (2.5, 5 and 10 mg/kg) reduced the response induced by nicotine plus apomorphine but not that elicited by apomorphine alone. The results indicate that the nicotinic receptor mechanism(s) may interact with apomorphine-induced licking in rats. Although central nicotinic and cholinergic mechanisms may be involved in the licking induced by apomorphine, peripheral nicotinic mechanism may be involved in the nicotine-induced increased apomorphine effect.