Abstract
Cold-pressed oils (CPO) are commercially available in the market and characterized by their health-promoting properties. Clove oil (CLO), coriander seed oil (COO) and black cumin oil (BCO) were evaluated for their bioactive lipids. Pharmacological screening was performed to evaluate acute toxicity, anti-inflammatory and ulcerogenic effects as well as histopathological changes in tissues of albino rats fed with CPO. Fatty acids, tocols and total phenolics were analyzed. The acute toxicity test for each CPO was estimated during 14 d. Carrageenan-induced rat paw oedema was used for assessment of anti-inflammatory activity of CPO. Animals were fasted overnight, and via oral gavage given indomethacin (10 mg/kg) or CPO (400 mg/kg) to investigate ulcerogenecity. Histopathological changes in liver, kidney, heart, spleen and stomach were screened. Results shown amounts of α-, β-, γ- and δ-tocopherols in CLO were 1495, 58, 4177 and 177 mg/kg oil, respectively. In COO, α, β, γ and δ-tocopherols were 10.0, 18.2, 5.1 and 34.8%, respectively. In BCO, β-tocotrienol was the main constituent. CLO, COO and BCO contained 4.6, 4.2 and 3.6 mg GAE/g, respectively. Acute toxicity test determined that 400 mg/kg of CPO to be used. In the carrageenan model of inflammation, pretreatment of rats with indomethacin (10 mg/kg) or CLO (400 mg/kg) induced a significant (p < 0.05) reduction by 31.3 and 27.4%, respectively, in rat paw oedema as compared with the carrageenan-treated group. Indomethacin induced a significant ulcerogenic effect with an ulcer index of 19. Oral treatment of CPO showed no ulcerogenic effect, wherein no histopathological changes were observed. In conclusion, CPO, particularly CLO, could minimize acute inflammation.