Antimicrobial Activity, Brine Shrimp Cytotoxicity and Phytochemical Composition of Croton Dichogamus Pax Crude Root Extracts From Kisumu East Subcounty

Abstract

The emergence of drug resistant strains of microbes has necessitated a hunt for more efficacious antimicrobials from the environment. As such, Greeneries (plants) have confirmed to be highly accumulated in potent medicinal values. In the current research the cytotoxicity, phytochemical constituents and antimicrobial activity of the crude root extracts of Croton dichogamus were evaluated. Croton dichogamus is a twig growing in Eastern Africa, where it is used as an anti-infective and tonic agent. The roots were obtained from collected from Kisumu East subcounty, then dried, milled and extracted using distilled water, acetone and 50% ethanol. The percentage yield of acetonic, aqueous and hydroethanolic extracts were 1.29%, 6.05% and 4.9% respectively. Microbroth dilution and agar well diffusion methods were used to estimate the antimicrobial activity of the extracts against five microorganisms. The cytotoxicity of the extracts was determine using brine shrimp bioassay. The fungal organism (C. albicans) together with the gram-positive bacteria (S. aureus, B. cereus) were considerably inhibited by the three root extracts while the gram-negative bacteria (E. coli, P. aeruginosa) were not inhibited by any of the three extracts at a concentration of 250mg/ml. Acetonic extract on B. cereus demonstrated the greatest antimicrobial activity giving a MIC of 10.42mg/ml and a zone of inhibition of 17.33±0.58 at a concentration of 250mg/ml. The LC50 values of acetonic, aqueous and hydroethanolic extracts (4.148μg/ml, 42.61μg/ml, 76.09μg/ml) were found to be below 100μg/ml which meant that all the extracts were highly cytotoxic. Saponins, anthracenes, flavonoids, tannins, phenols, terpenoids and polyuronides were the phytochemical components present. The current study reports that C. dichogamus had antimicrobial activity thus confirming the folklore claim. These results make a strong case for..........................................................................................