Evaluation of antibacterial activity of leaf extracts of Mansoa alliacea (Lam.) A.H. Gentry, Tecomaria capensis (Thunb.) Spach and Tecoma stans (L.) Juss. Ex H. B. & K.
By: Sundas Iltaf, Zaheer-Ud-Din Khan, Rizwana Rafique, Anjum Parveen
Key Words: In vitro antibacterial activity, Mansoaalliacea, Tecomastans, Tecomariacapensis, Agar well diffusion.
J. Bio. Env. Sci. 9(1), 69-75, July 2016.
The current investigation was carried out to evaluate the antibacterial potential of different extracts (n-hexane, chloroform, ethanol and aqueous) of the leaves of Mansoa alliacea, Tecomaria capensis and Tecoma stans, belonging to family Bignoniaceae, using agar well diffusion method against 2 Gram-positive bacteria, i.e. Bacillus subtilis, Staphylococcus aureus and 2 Gram-negative bacteria, i.e. Escherichia coli and Pseudomonas aeruginosa. The diameter of inhibition zone of the leaf extracts were compared with those of different standards like ampicillin (10µg), amikacin (30µg) and the significant inhibition of the growth of bacteria was shown by leaf extracts against the test microbes, e.g. in Tecomaria capensis, 45.36mm and 42.33mm by n-hexane extract against S. aureus and by chloroform extract against E. coli, respectively. Highest percentage extraction yield was exhibited by the aqueous extract of leaves, i.e. 12.52, 15.48 and 17.98 for Mansoa alliacea, Tecoma stans and Tecomaria capensis, respectively. The ranges of Minimum Inhibitory Concentration (MIC) were 10-2.5mg/mL for Mansoa alliacea and Tecoma stans, while it was 10-1.25mg/mL for Tecomaria capensis. It suggested that these plants can be used as bioactive natural products to inhibit the growth of pathogenic bacteria.