Mirabilis jalapa Linn. is widely used as a traditional medicine in many parts of the world for the treatment of various diseases. The methanol, acetone, chloroform and diethyl ether extracts from different varieties of M. jalapa were screened for phytochemical analysis and antibacterial activities. Phytochemical analysis showed the presence of Alkaloids and glycosides were detected only in the methanolic extracts of all varieties, but were not detected in the other solvent extracts, viz. acetone, chloroform and diethyl ether. Flavonoids and terpenoids were detected in all the four solvent extracts of each variety. Among the four different solvents used for the extraction, the methanol extracts followed by acetone extracts of all variety showed maximum inhibitory activity than the diethyl ether and chloroform extracts. However the methanolic leaf extract of the white flowered variety showed highest antibacterial activity against all organisms at 500 mg/ml concentration. Best activity was observed against S. aureus NCIM 5021 followed by B. subtilis NCIM 2063, P. aeruginosa NCIM 5029 and E. coli NCIM 2931. Then second best antibacterial activity was shown by 500 mg/ml concentration of methanolic leaf extracts of pink flowered variety, followed by yellow and orange flowered variety, respectively.
