Exploring the pharmacological significance of Murraya koenigii (L.) Spreng: Insights from North-East India

Murraya koenigii (L.) Spreng., is a renowned medicinal and aromatic plant having antimicrobial and broad biological activities. In the present study, the essential oil chemical profile of the leaf and floral part were analysed using GC-FID and GC-MS, and the antimicrobial activities were determined by disk diffusion assay. The scientific analysis revealed α-pinene (40.41%) was the major compound of leaf essential oil (MKL) followed by sabinene (29.66%), β-pinene (7.92%), caryophyllene (4.24%), limonene (3.39%), terpinen-4-ol (3.25%), γ-terpinene (2.63%), terpinolene (1.58%), linalool (1.32%), along with other trace components. The floral part (MKF) contains the compounds α-pinene (74.02%) as the major compound followed by β-pinene (7.17%), sabinene (5.72%), limonene (4.19%), β-myrcene (1.98%), γ-terpinene (1.47%) and terpinen-4-ol (1.41%) along with other trace compounds. The MIC result revealed essential oil showed effectiveness against Escherichia coli (40 μg/mL), Micrococcus luteus (80 μg/mL), Aspergillus fumigatus (60 μg/mL) and Aspergillus brasiliensis (80 μg/mL) for MKL while MKF did not exhibit potent antimicrobial activities. The essential oils revealed potent antioxidant potential as determined by DPPH method with IC50 values of 14.02 μL/mL (MKL) and 5.45 μL/mL (MKF) and the ABTS method with IC50 values of 5.07 μL/mL and 8.38 μL/mL in MKL and MKF respectively as compared to that of the standards. The essential oils revealed potent antidiabetic activity with 6.02 μL/mL (MKL) and 8.18 μL/mL (MKF) as that of the standard. However, both MKL and MKF were not much effective in protease inhibitory activity and anti-tyrosinase activity. The study results exhibited a potent bioactivity profile and revealed many new utilization aspects of this essential oil.