Author(s): S. Sujatha and Akila Suresh
Profound research has been done on the medicinal value of Brassica nigra (BN) seeds, and the leaves of the plant have been investigated in this study. The methanol extracts of the leaves were subjected to several in vitro studies. Among the four parts of this experimental plant seed extracts, which showed better antimicrobial activity in the initial screening test, were selected for further investigations. Though a floral extract with chloroform solvent showed refusal activity against five tested bacteria. However, maximum zone of inhibition observed in seed extract with polar and non polar solvents such as Pet. Ether, Chloroform and methanol against S. aureus (17.90 ± 2.1), P. mirabilis (17.8±4.02), E. aerogens (15.71.4±0.2), P. vulgaris (14.7±2.8), E. coli (11.47±3.3). Comparison of the antimicrobial activities of the fractions with that of the crude extract indicated that the non-polar fractions in many cases are stronger in activity at the two concentration levels than the crude extract. Results of the present study indicated that seed extracts with polar and nonpolar solvents can be exploited for future antimicrobial drugs against selected pathogenic bacterial strain.