Phytochemical and Biological Studies of Carissa macrocarpa, F. Apocyanaceae

The present work comprises the isolation, purification and identification of eight known compounds obtained from the powdered leaves & stems of Carissa macrocarpa (F. Apocyanaceae) named; α-amyrin acetate (1), α-amyrin (2), lupeol acetate (3), stearic acid (4), ursolic acid (5), β-sitosterol-3-O-β-D-glucopyranoside (7), quercetin (7) and kaempferol-3-O-rutinoside (8). The structural elucidations of the isolated compounds were confirmed on the basis of their physical, chemical, chromatographic and spectroscopic methods. In addition; the study of some biological activities of Carissa macrocarpa 70% methanolic extract (CMME) and its fractions (n-hxane, dichloromethane (DCM), ethyl acetate (EtOAc) and n-butanol). The biological evaluations included cardiovascular activity, together with anti-inflammatory & antipyretic and antimicrobial activities. CMME and its fractions showed promising increase in the force of contractility (positive inotropic effect) and decrease in the heart rates (negative chronotropic effect) of the isolated rabbit's heart. They showed hypotensive effect on the rabbits mean arterial blood pressure (MABP). The EtOAc and DCM fractions showed the maximum anti-inflammatory activity after 5 h. (100 mg/kg) with percentage of inhibition 43% and 41%, respectively, in comparison with indomethacin reference drug (47%, 10 mg/kg). Yeast-induced hyperpyrexia method was used for antipyretic activity. The CMME and n-butanol fraction showed the highest antipyretic activity after 5 h. The CMME and fractions provided remarkable antibacterial activity. The EtOAc fraction showed the most potent effect against the tested microorganisms Bacillus subtilis & Staphylococcus aureus (Gram +ve bacteria) and Escherichia coli & Pseudomonas aeruginosa (Gram -ve bacteria).