THE ANTIBACTERIAL ACTIVITY AND PHYTOCHEMICALS OF THE LEAVES OF STYLOSANTHES FRUTICOSA

Abstract

The antibacterial activity and phytochemicals of the leaves of Stylosanthes fruticosa were evaluatedagainst three Gram-positive bacteria viz. Bacillus cereus, Staphylococcus faecalis ,Staphylococcus aureusand five Gram-negative bacteria viz. Klebsiella pneumonia Pseudomonas aeruginosa, Escherichia coli, Salmonella typhimurium ,and Proteus vulgaris. Both polar and nonpolar extracts viz. acetone, chloroform, ethanol,  and aqueous extracts were prepared and studied for antibacterialactivity using disc diffusion method. The majority of the significant antibacterial activity was observed in the ethanol extracts. The other solvent extracts showed satisfactory results. In general, gram-negative bacteria are more resistant to antibiotics than gram-positive bacteria . The resistance is due to the differences in their cell wall composition. In gram-negative bacteria the outer membrane acts as a great barrier to many environmental substances including antibiotics. Presence of thick murine layer in the cell wall prevents the entry of the inhibitors . But our results revealed a controversy report that gram-positive bacteria are more susceptible to the crude extracts than gram-negative bacteria.. Theresults which are obtained with acetone, ethanol  and chloroform extract ofleaf exhibited significant antibacterial activity, a property that supports traditional use of the plant inthe treatment of some diseases as broad spectrum antibacterial agents.