Comparative Phytochemical Analysis andAntimicrobial Activity of Four Medicinal Plants

摘要

The present study was aimed to evaluate the phytochemical constituents and antimicrobial activity of the leaf and stem extracts of Ricinus communis, Solanum nigrum, Clerodendrum infortunatum and Calotropis gigantea. The selected plants were made a comparative study of medicinal value. The result of phytochemical analyses revealed that chemical diversity in aqueous and ethanol leaf extracts of R. communis which showed the presence of flavonoids, steroids, carbohydrates, proteins, tannins, glycosides, terpenoids, alkaloids, phenols, glycosides and anthraquinones. Phytochemical compound is comparative less in ethyl acetate extracts of leaf from S. nigrum, C. infortunatum and C. gigantea. In Total Phenol Content assay (TPC), the highest concentration of phenols was found in ethanol leaf extracts of R. communis (800 mg GAE/100 g) and the less amount of TPC recorded in aqueous extracts of C. infortunatum (20 mgGAE/100 g). The Total Flavonoids Content assay (TFC) value followed similar trend the highest concentration was found in ethyl acetate leaf extracts of R. communis (450 mg CE/100 g) and the absent in aqueous extracts of C. gigantea and C. infortunatum. The antimicrobial activities of aqueous, methanol and ethanol extracts leaf and stem were determined on selected bacteria, Escherichia coli, Bacillus subtilis and the fungus, Curvularia lunata. The result indicates that the aqueous and methanol leaf extracts of R. communis were showed strong antimicrobial activity against Escherichia coli and Bacillus subtilis at a concentration of 100 mg/ml respectively. Even ethanol leaf extracts of Ricinus communis showed better zone of inhibition diameter 45±0.65 mm compared to other plants extract against fungus, Curvularia lunata.