title: Anti-inflammatory and antioxidant activities and constituents of Platostoma africanum P. Beauv.
abstract: Hexane and dichloromethane extracts of Platostoma africanum P. Beauv., a plant popularly employed in Nigeria in the treatment of rheumatic symptoms, were evaluated for anti-inflammatory and antioxidant activities. Acute inflammatory effects were studied in the egg-albumin-induced rat paw edema. Both extracts produced significant (p < 0.05) and dose-dependent inhibition of the egg-albumin-induced pedal edema with the 400 mg kg(-1) dose being markedly better than piroxicam. The hexane and dichloromethane extracts also showed significant antioxidant activity with the dichloromethane extract exhibiting an IC(50) comparable to that of BHT, a synthetic antioxidant. Phytochemical investigation of the extracts afforded eight acidic pentacyclic triterpenes, namely, ursolic acid, oleanolic acid, epimaslinic acid, maslinic acid, corosolic acid, hyptadienic, euscaphic acid and tomentic acid, and a mixture of beta-sitosterol and stigmasterol. These constituents are reported for the first time in the genus.
authors.affiliation: Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, AB, Canada. felix.aladedunye@uleth.ca
authors.forename: Felix A
authors.initials: FA
authors.lastname: Aladedunye
authors.forename: Domingo A
authors.initials: DA
authors.lastname: Okorie
authors.forename: Osasenega M
authors.initials: OM
authors.lastname: Ighodaro
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019686:Lamiaceae / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D010936:Plant Extracts