ANTIBACTERIAL ACTIVITY OF PHYTO-CHEMICALS OBTAINED FROM LEAFEXTRACTS OF SOME MEDICINAL PLANTS ON PATHOGENS OF SEMI-ARID SOIL

Plants being the major source of natural products like vitamins, minerals, immune–modulators, possess anti-pathogenic activities and act as good source of antimicrobial agents. Thismakes plants to occupy importance in traditional medicine. The phytochemical analysis revealed thepresence of metabolites such as saponin, flavonoid, alkaloid, carbohydrate, glycoside, tannin and oilphenolic compound responsible for the antibacterial activity of these plants. Diffusion and dilutionmethods have been, employed to study the comparative antimicrobial activities of extracts of plantsNeem (Azadirachta indica) Tulsi (Ocimum sanctum) and Aloe vera. The extracts of these plants understudy, were used against bacteria isolated from the semi-arid soil in Banasthali region, the strainsidentified are Escherichia coli, Pseudomonas fluorescence, Bacillus subtilis, Bacillus cereus and Staphylococcusaureus. Azadirachta indica showed maximum inhibition against S.aureus, whereas Ocimum sanctumshowed maximum zone against E.coli and Aloe vera against Pseudomonas fluroscens. The aqueousextracts of various leaves were investigated individually for antimicrobial activity against thesepathogens and showed less inhibitory activity against most of the test bacterial pathogens.