PHYTOCHEMICAL SCREENING AND ANTIMICROBIAL ACTIVITY OF EXTRACTS OF COCHLOSPERMUM TINCTORIUM AND CASSIA SINGUEANA

Abstract

Typhoid fever is a common disease reported in Africa and remains a major public health concern in recent times. While several factors contribute to this health challenge, it is primarily associated with pathogens such as Salmonella typhi and other microorganisms present in the environment. In this study, four clinical isolates (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi) were used to test for the antibacterial activity of Cochlospermum tinctorium and Cassia singueana. Four solvents—ethyl acetate, n-hexane, methanol and chloroform—were used for the extraction of active components from air-dried pulverized plant materials using cold maceration. Antibacterial activity was evaluated using the agar well diffusion method at a concentration of 2000 µg/mL. Phytochemical screening and FTIR analysis of chromatographically separated fractions were also conducted. Methanol extracts showed the highest antibacterial activity, with inhibition zones of 27 mm and 25 mm against E. coli and Staphylococcus aureus respectively for Cochlospermum tinctorium, and up to 23 mm against Salmonella typhi for Cassia singueana. Other solvent extracts showed moderate activity ranging from 10–17 mm. Phytochemical screening revealed the presence of tannins, saponins, glycosides, alkaloids and related secondary metabolites in both plant materials. FTIR analysis of purified fractions revealed functional groups such as alkanes, alkenes, aldehydes and hydroxyl-containing compounds. The findings from this study indicate that Cochlospermum tinctorium and Cassia singueana possess bioactive compounds with notable antibacterial activity, supporting their traditional medicinal use. However, the results are preliminary, and further studies involving compound isolation, toxicity evaluation, and in vivo analysis are required to establish their full therapeutic potential.