Phytochemistry and Antimicrobial Activity of Rhizome Extracts of Amomum nilgiricum from the Western Ghats, India

摘要

Rhizomes of Amomum nilgiricum successively extracted in hex-ane, chloroform, ethyl acetate, acetone, methanol, and water were analyzed for their phytochemistry and antimicrobial activities. A. nilgiricum had the highest concentration of tannins (9.5 mg TAE g~(-1)) in its methanol extract followed by alkaloids (9.46 mg AE g~(-1)), saponins (8.32 mg DE g~(-1)), flavonoids (8.38 mg QE g~(-1)), phenolics (6.96 mg GAE g~(-1)), and steroids (5.43 mg CE g~(-1)). The highest inhibition zone observed was withethyl acetate extract against Pseudomonas aeruginosa (21.12 mm at 25 mg mL~(-1)), while in fungi the highest zone of inhibition was with methanolic extract against Aspergillus flavus (18.98 mm at 25 mg mL~(-1)). The minimum inhibitory concentrations (MICs) of ethyl acetate and methanol extracts were at 6.25 ug mL~(-1) against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella typhi-murium, Proteus vulgaris, and Klebsiella pneumoniae. The MICs of fungi were noted in methanol extract at 25 ug mL-1 against Aspergillus flavus, A. terreus, A. niger, and Fusarium oxysporum.