Anti-inflammatory, analgesic and antipyretic properties of Thespesia populnea Soland ex. Correa seed extracts and its fractions in animal models

Thespesia populnea Sol. ex Correa (Malvaceae) is commonly known as “Indian tulip tree”. The plant has been used as an astringent, antibacterial, anti-inflammatory, antinociceptive and hepatoprotective in Indian system of traditional medicine. Thespesia populnea seeds were successively extracted by soxhlet extraction using petroleum ether (40–60°C) (TPO) and ethanol (TPE). Unsaponifiable matter (TPOUM) and fatty acids were separated from seed oil. A GC–MS analysis of fatty acid methyl esters was carried out. Ethanolic extract was fractionated using CHCl3, EtOAc, n-BuOH and H2O. Acute arthritis was induced by sub-plantar injection of carrageenan into the left hind paw of rats. The paw volume was measured using plethysmometer. Analgesic activity was assessed by heat induced pains (tail immersion model) and antipyretic activity assessed using brewers yeast-induced pyrexia model. Oral administration of TPO and TPE at 200 and 400mg/kg b.w. and tested fractions at 200mg/kg significantly reduced carrageenan induced paw edema and brewers yeast-induced pyrexia. In tail immersion method also extracts and fractions showed significant analgesic activity. Amongst all fractions EtOAc showed most significant results. TPOUM showed significant anti-inflammatory and analgesic activity. GC–MS analyses showed the presence of fourteen fatty acids, predominant fatty acids were palmitic and stearic acid. These results highlighted anti-inflammatory, analgesic and antipyretic effects of Thespesia populnea seeds.