Abstract

Following an ethnobotanical survey for hepatoprotective remedies, four Libyan medicinal plants from family Lamiaceae; Ajuga iva (L.) Schreber, Marrubium vulgare L., Rosmarinus officinalis L. and Thymus capitatus Hoff. et Link growing widely in Beida, Libya, were selected for our study. The chemical composition of essential oils hydrodistilled from the dried aerial parts, were analyzed by gas chromatography-mass spectrometry (GC-MS). The major constituents of the essential oils of A. iva and R. officinalis were carvacrol (35.07%) and 1,8-cineol (35.21%), respectively, thymol was the major constituent of the essential oil ofM. vulgare (20.11%) and T. capitatus (90.15%). The oil of M. vulgare had the most powerful antioxidant activity by restoring glutathione levels in the blood of alloxan-induced diabetic rats. The rats treated with the essential oils of M. vulgare, R. officinalis and T. capitatus (50 mg/kg) showed a significant decrease in liver enzymes which were elevated by CCl₄ (p Ë‚ 0.01). The essential oil of M. vulgare had the most potent hepatoprotective activity.

Key words: Ajuga iva, Marrubium vulgare, Rosmarinus officinalis, Thymus capitatusantioxidant, hepatoprotective.