Antipyretic and antiinflammatory properties of methanolic extracts of kigelia africana (lam.) Benth and acacia hockii de wild in animal models

ABSTRACT

Pyrexia and inflammation cause discomfort, suffering and lower productivity of the victims. Non-steroidal anti-inflammatory drugs which are highly prescribed in medication of pyrexia and inflammation have been reported to possess adverse effects. Herbal medicines may possess bioactive compounds that are safer and efficient in the management of various diseases and disorders. Kigelia africana and Acacia hockii are traditionally used to manage pyrexia and inflammation among the Embu and Mbeere communities in Kenya but there lacks scientific data to support their use. The present study determined antipyretic and anti-inflammatory activities of the two extracts in animal models to scientifically confirm their traditional use. The plant samples were collected with the help of local herbalists in Embu County, Kenya and transported to Kenyatta University for cleaning, air drying, milling, and extraction in Biochemistry and Biotechnology laboratories. Animal models were randomly divided into six groups of 5 animals each; three experimental groups (50, 100 and 150mg/kg body weight), normal control group, negative control group and positive control group. The antipyretic effect was determined using turpentineinduced pyrexia, while the anti-inflammatory effect was determined using carrageenan-induced hind paw edema method. The antipyretic and anti-inflammatory activities of the extracts were compared to reference drugs aspirin and diclofenac respectively. The stem bark extract of K. africana reduced the elevated rectal temperature by between 0.06 and 3.07 percent, while the stem bark extract of A. hockii reduced the raised rectal temperature by between 0.62 and 3.88 percent. The aspirin reduced the rectal temperature of pyretic rats by between 0.63 and 3.1 percent. The leaf extract of K. africana reduced inflamed hind paw diameter of mice by between 0.21 and 4.98 percent, while the stem bark extract of A. hockii reduced inflamed hind paw diameter by between 0.6 and 5.38 percent. The diclofenac reduced inflamed hind paw diameter by between 1.11 and 4.9 percent. The qualitative phytochemical screening indicated the presence of flavonoid, alkaloids, steroids, saponins, terpenoids, phenolics, and cardiac glycosides. The present study demonstrated potent antipyretic and anti-inflammatory activities of methanolic extracts of K. africana and A. hockii in a dose-dependent manner, which supports their traditional use. The present study, therefore, recommends that K. africana and A. hockii can be used as a potential candindate in development of antipyretic and anti-inflammatory agents.