Bioactive Screening and Antimicrobial Activity of Selected Three Medicinal Plants on Chosen Microbes

Leaf extracts were used for the treatment of gastroenteritis, arthritis, typhoid fever and wound infections. The study also investigated the chemical constituents of the plant and the effect of temperature and pH on its antimicrobial activity. The phytochemical constituents of the dried powdered leaf were extracted using aqueous and organic solvents (Benzene and methanol). The antimicrobial activity of the concentrated extracts was evaluated by determination of the diameter of zone of inhibition against both gram negative and gram positive bacteria and fungi using the paper disc diffusion method. Results of the phytochemical studies revealed the presence of alkaloids, tannins, saponins, glycosides and phenols and the extracts were active against bacteria and fungi. The effect of temperature on the antimicrobial activity of leaf extracts of three plants showed that the activity of extracts increased with an increase in temperature(35°C,45°C,55°C), but was reduced at alkaline pH(5,7,8). The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the extracts ranged between 50–200 mg/ml. Acmella olerece, Clerodendron infortunatum and Ficus bengalensis have broad spectrum antibacterial activity and a potential source of new classes of antibiotics that could be useful for infectious disease.