Phytochemical and Bioanalytical Studies on Murraya koenigii Leaves and Exploring its Pharmaceutical Properties

The curry leaf plant Murraya koenigii is a widely consumed edible plant in Indian subcontinent for its nutritional benefits. Different parts of this plant have been proved to exhibit various pharmaceutical activities. The phytochemical analysis of aqueous leaf extract of M. koenigii indicted the presence of tannins, saponins, steroids, terpenoids and cardiac glycosides. The antimicrobial properties of five solvent extracts of M. koenigii leaves were tested against six pathogenic strains of microbes using agar well diffusion method. The MICs of methanol extract for the bacteria Staphylococcus aureus, Escherichia coli and Salmonella typhi were 250, 750 and 1000µg/mL respectively. While the acetone extract completely inhibited the bacteria E. coli (≥250µg/mL), it could exhibit the lethality only at high concentrations (≥1000µg/mL) for S. aureus and S. typhi. Moderate effects were shown by ethanol and chloroform extracts with the MICs ranging 750 - 1000µg/mL against the bacteria. The ethyl acetate extract was effective only against E. coli (250µg/mL). The methanol extract inhibited all the fungi with the MICs of ≥1000µg/mL against both Aspergillus niger and Trichophyton rubrum and ≥750µg/mL against Candida albicans. Acetone extract caused moderate (≥750µg/mL) and complete inhibition (≥250µg/mL) respectively of A. niger and C. albicans. The ethyl acetate, ethanol and chloroform extracts were effective only against C. albicans with the MICs ranging 500 - 1000µg/mL. The TLC and GC-MS studies revealed the occurrences of 7 and 13 secondary metabolites respectively in the M. koenigii leaf extracts encompassing three compounds with proven bioactive potentials.