Abstract:
The present study investigates antibacterial activity of tobacco extracts from Nicotiana tabacum at different
concentrations in different polar solvents. Six different extracts were prepared, using 5 different polar solvents viz., Ethanol, Ethyl acetate, n-Hexane, Acetone, Butanol and water. Four different concentrations (6, 12, 18 and 24 mg of sample disc-1) of each extract were subjected for preliminary antibacterial screening against seven pathogenic bacteria by Kirby-Bauer Disk Diffusion method. The result of in vitro antibacterial screening showed that 6 extracts from Nicotiana tabacum revealed different ranges of antibacterial activities. Ethyl acetate extracted samples were more effective to control Bacillus cereus and Erwinia carotovora followed by butanol extracted samples against Staphlococcus aureus and Agrobacterium tumefaciens, while no significant nhibitory effects were observed in ethanol and hexane extracts. When tobacco extracts were studied for their antibacterial potential against gram-positive and gram-negative bacteria, the ethyl acetate extracts showed a good range of inhibitory effects against Bacillus cereus and Erwinia carotovora at highest concentration (24 mg
sample disc-1). Hexane, ethanol and aqueous extracts did not show a significant range of inhibitory effect but acetone extracts indicated non significant inhibitory effects against S typhae, Staphlococcus aureus and Erwinia carotovora
