Phytochemical analysis and antimicrobial evaluation of Andrographis lineata Nees leaves and stem extracts

The present investigation was designed to evaluate the antibacterial, antifungal properties and physiochemical screening of the various leaves and stem extracts of Andrographis lineata. Acetone, ethanol, methanol, petroleum ether and chloroform extracts of shade dried plant leaf and stem of A. lineata were tested for antibacterial, antifungal and phytochemical analysis. The antibacterial properties of various extracts of leaves and stem of A. lineatawere assayed using the standard disc diffusion method, against five strains of bacterial species, namely, Proteus vulgaris, Escherichia coli, Klebsiela pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa. Among different solvent extracts studied, the methanol leaf extract showed highest antibacterial activity against staphylococcus aureus(19.41 mm); followed by petroleum ether extract (18.30 mm). The highest inhibition zone observed for acetone extract of A. lineata leaves against P. vulgaris was 17.40 mm followed by ethanol extract (16.10 mm). The highest activity of chloroform extract against K. pneumoniae was 14.07 mm. Phytochemical investigation confirmed the presence of flavonoids, saponins, gums and mucilages, triterpenoids, steroids, glycosides, phenolic compounds and tannins. The acetone leaf extracts of A. lineata showed highest antifungal activity against Penicillium pinophilum (13.40 mm). The methanol leaf extracts showed maximum activity against Aspergillus niger (12.15 mm). The petroleum ether leaf extracts showed highest activity against P. pinophilum (12.11 mm). The ethanol leaf extracts showed significant activity against Aspergillus flavus (11.24 mm). The chloroform leaf extracts showed higher activity against A. niger (9.75 mm). The leaf extract showed more inhibitory effect than the stem extracts. The present research justifies the claimed uses of this herb in the traditional system of medicine to treat different diseases. Key words: Andrographis lineata, antibacterial activity, antifungal activity, phytochemicals, agar well diffusion method.