Antimicrobial activity and phytochemical analysis of Andrographis alata Nees from Southern India.

Andrographis alata Nees is an important medicinal plant. The current study was to investigate the antibacterial, antifungal activity and phytochemical analysis of the various leaf and stem extracts of A.alata. Methanol, ethanol, chloroform, acetone and petroleum ether extracts of shade dried plant leaf and stem of A.alata were tested for antibacterial, antifungal and phytochemical screening. The antibacterial activity of different extracts (methanol, acetone, ethanol, chloroform and petroleum ether) of leaves and stem of A.alata using the standard disc diffusion assay against five strains of antibacterial species, viz., Escherichia coli, Proteus vulgaris, Staphyllococcus aureus, Pseudomonas aerusinosa and Klebsiella pneumoniae. Among various solvent extracts studied petroleum ether leaf extract showed a highest antibacterial assay followed by chloroform, ethanol, acetone and methanol. A phytochemical screening was conducted on the leaf and stem extracts using standard qualitative methods that revealed the presence of saponins, flavonoids, triterpenoids, gums and mucilages, glycosides, steroids, tannins and phenolic compounds. The chloroform leaf extract of A.alata showed most active against Alternaria alternata. The ethanol leaf extracts showed high antifungal activity against Aspergillus niger. The methanol leaf extracts showed significant activity against Aspergillus flavus. The petroleum ether leaf extracts showed high against Fusarium solani. The acetone leaf extracts showed highest antifungal activity against Penicillium pinophiium. The present study justifies the claimed uses of this herb in the traditional system of medication to treat various sickness. This is the first report wherein antibacterial, antifungal and phytochemical analysis from A.alata leaf and stem.