PHYTOCHEMICAL ANALYSIS OF MEDICINAL HAWKED HERBS USED IN THE TREATMENT OF MALARIA AND TYPHOID FEVER

ABSTRACT Plants play a crucial role in human health and well-being. They provide some of the essential nutrients that humans require as well as act as medications to alleviate and cure various health problems. Pterocarpus osun (family: Fabaceae) is utilized in the traditional treatments of diarrhea and dysentery. This study evaluated the antibacterial and cytotoxicity potentials of P. osun leaf and stem extracts intending to validate its use in folk medicine. The stem bark and leaves of P. osun were collected and air dried and separately pulverized. Each powdered sample was extracted separately with 80% (v/v) methanol for 72 h and filtered. Filtrates were separately concentrated in vacuo to give methanol leaf and stem extracts. Antibacterial susceptibility test, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were carried out on ten clinical bacterial isolates using standard procedure. Cytotoxicity potential was also evaluated based on established procedures. Therapeutic index (TI) and potency level were determined based on established protocols. Results showed that the stem extract had highest zone of inhibition (25 mm) against Serratia marcesens (NCIB 1377) while leaf extract had 22 mm against Micrococcus luteus (NCIB 167) as compared with streptomycin and ampicillin. Also P. osun stem extract had MIC 0.391 mg/ml for E. coli, S. marcesens, P. aeruginosa and S. aureus; and MBC 0.391 mg/ml for B. cereus, P. vulgaris, B. subtilis, P. aeruginosa, V. fluvialis (LIO), and K. pneumoniae. The leaf extract had MIC 0.271, 0.465, and 0.548 mg/ml against B. cereus, P. vulgaris, M. luteus; and MBC 0.232 and 0.278 mg/ml for B. subtilis and V. fluvialis. The leaf extract had TI 0.49, 0.53, 0.48, 0.38, and 0.14 against while the stem extract had TI 0.67, 0.53, 0.56, 0.32, and 0.18 against S. aureus, E. coli, K. oxytoca, S. enterica and S. sonnei respectively. The leaf and stem extracts showed cytotoxicity effect at LD50 0.2341 and 0.3478 mg/ml respectively. Flavonoids, tannins, saponins, glycosides, triterpenes, xanthoproteins, and anthraquinone were present in both leaf and stem extracts while alkaloid was absent. The study concluded that the leaf and stem extracts of Pterocarpus osun showed broad spectrum antibacterial activity and therefore, supported their use in ethnomedicine.