Abstract

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The present study evaluates the phytochemical composition of ethanolic extract and antimicrobial property of ethanolic and aqueous extracts of Nicotiana tabacum. The antimicrobial effects of Nicotiana tabacum (tobacco) leaf extract on microbial isolates (Staphylococcus aureus and Escherichia coli) was evaluated using using agar well diffusion method. Also, the Phytochemical screening of the plant was done using standard chemical methods. Phytochemical screening of ethanol extract of N. tabaci detected the presence of alkaloids, tannins, saponins, flavonoids and cyanogenic glycosides. The antimicrobial effects of tobacco leaves using ethanol and water showed that the extract inhibited the growth of Staphylococcus aureus and Escherichia coli by a diameter of 2.8 and 3.6cm respectively while water extract inhibited the organisms by a diameter of 1.2 and 1.4cm respectively. At a concentraton of l.OOmg/ml of Nicotiana tabacum leaf extract Staphylococcus aureus, an inhibition of 2.3cm was observed while on Escherichia coli, the same concentration of the extract inhibited 2.8cm The mineral estimate in N. tabaci leaf using atomic absorption spectrophotometer (AAS) showed that Fe is 648.53mg/kg, Mg, 640.33mg/kg, Na, 7021.30mg/kg, K, 3128.63mg/kg, Ca, 17,551.33mg/kg, and Zn, 46.30mg/kg. The result of this study validates the use of tobacco leaf extract as snuff in treatment of cold and catarrh as it is commonly used by the elderly in Eastern Nigeria and can also be used in eliminating infections caused by gram positive and gram negative bacteria.

Keywords: antimicrobial, Nicotiana tabacum, phytochemical, pathogens