PHYTOCHEMICALS AND BIOLOGICAL ACTIVITIES FROM THE CONSTITUENTS OF CASSIA ANGOLENSIS GROWING IN TANZANIA

Abstract

This study was carried out to isolate and characterize constituents from the leaves, stem and roots ethanolic extracts of the Cassia angolensis and evaluate the antibacterial and antimalarial activities. Therefore, compounds of flavan-3-ol nature including epiafzelechin (1) as well as epicatechin (2) were isolated and characterized. Biological activities of isolated compounds were not evaluated due to small amount of sample obtained during isolation. The ethanolic root extract showed the maximum zone of inhibition of 11 mm with an activity index (AI) of 0.45 and Minimum Inhibitory Concentration (MIC) of 0.3 mg/mL against Staphylococcus aureus (ATCC 25923). Furthermore, the ethanolic leaves extract showed activity at MIC 0.6 mg/mL against S. aureus and 1.25 mg/mL against Klebsiella pneumoniae (ATCC 708903), Pseudomonas aeruginosa (ATCC 27853) and Escherichia coli (ATCC 25922). The stem ethanolic extract was the least active compared to the rest, showing an activity of 2.5 mg/ mL against E. coli, S. aureus and K. pneumonia and 5.0 mg/mL against P. aureginosa. On the other hand, antimalarial tests showed notable significant (P < 0.05) parasitaemia (P. berghei) suppression at 92.9% and 93.5%, for root and leaves extracts, respectively at 300 mg/kg body weight dosage. The results reported herein, correlates with the local use of the plant for treatment of malaria and other ailments, therefore, revealing the potentiality of the plant in the treatment of both malarial and bacterial infections.