Phytochemical analysis and antibacterial activity of fractions of Sida acuta against some reference isolates of bacteria

Abstract

The use of medicinal plants could be an excellent source of drugs to overcome the problem of antibiotic resistance. This study was undertaken to determine the phytochemical analysis and antibacterial activities of Ethanol leaf extract fractions of Sida acuta against Escherichia coli (ATCC 43888), Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 9027) and Bacillus subtilis (ATCC 6633). The phytochemical constituents of the fractions of the crude extract were determined using standard methods. Furthermore, the antibacterial activity of the leaf fractions against the reference isolates of bacteria were determined using agar well diffusion and broth dilution methods, at varied concentrations of the extract and using ciprofloxacin antibiotic as control. Preliminary phytochemical screening showed the presence of alkaloids, saponins, glycosides, tannins, flavonoids, cardiac glycosides, terpenes and phenols. The N-butanol and aqueous fractions of the leaf of S. acuta demonstrated significant antibacterial activities at (P ≤ 0.05) against the isolates of bacteria, while chloroform and ethyl acetate do not. The n-butanol fraction however, exhibited the highest activity against all bacterial isolates with MICs and MBCs of 37.5 mg/mL and 75.0 mg/mL respectively. Therefore, the observed antibacterial activities revealed that Sida acuta could be used for the treatment of infections caused by the test bacterial isolates.