Phytochemical Screening and Antibacterial Activity of Ficus thonningii Stem Bark Extracts

Abstract

The increasing emergence of antimicrobial resistance necessitates the search 
for new antibacterial agents, particularly from plant sources. This study 
investigates the phytochemical constituents and antibacterial activity of the stem 
bark of Ficus thonningii Blume, a traditionally used medicinal plant in Nigeria. 
Sequential extraction was conducted using n-hexane, ethyl acetate, and 
ethanol. . The extracts were subjected to qualitative phytochemical screening.  
The antimicrobial activity of the extracts was tested on Escherichia coli, 
Salmonella typhi, Staphylococcus aureus, and Streptococcus pyogenes using 
agar well diffusion and broth dilution methods. The phytochemical screening 
revealed the presence of alkaloids, flavonoids, tannins, saponins, steroids, 
cardiac glycosides and anthraquinones. The antibacterial activities of the 
extracts were tested against Escherichia coli, Salmonella typhi, Staphylococcus 
aureus, and Streptococcus pyogenes. The ethyl acetate extract showed the 
highest antibacterial activity, with inhibition zones ranging from 1.50 mm to 
17.00 mm particularly against Gram-positive bacteria. MIC and MBC tests 
confirmed its potency. These findings support the traditional use of Ficus 
thonningii in treating bacterial infections and highlight its potential as a source of 
plant-based antimicrobial agents.