Assessment of Chemical Composition and Therapeutic Acti-vities of Clausena excavata Burm.: An Important Medicinal Plant of Eastern Ghats of India

Abstract

Clausena excavata Burm. is an important medicinal plant belonging to the family Rutaceae. It is well known for its ethnomedicinal uses and therapeutic activities. This plant has been used in different traditional systems of medicine for the treatment of various diseases worldwide. In the present study, the chemical composition of essential oil and phytochemical contents of methanol extract of C. excavata leaf were performed. Further, the therapeutic activities of essential oil and methanol extract of C. excavata leaf were evaluated. The chemical composition of essential oil was analyzed by Gas Chromatography/Mass Spectrometry (GC/MS). Myristicin (33.92%), terpinolene (21.29%), and sabinene (13.65%) were found to be the major compounds in leaf essential oil. Similarly, the phytochemical composition of the methanol extract of C. excavata leaf was analyzed using standard procedures. The phenolic content (165.23 mg GAE/g DW) was found to be the major phytoconstituents followed by alkaloids (89.30 mg/g DW) in leaf methanol extract. Furthermore, the antioxidant, antidiabetic, anticancer, and antimicrobial activities of the essential oil and methanol extract were evaluated. C. excavata essential oil showed more antioxidant activity (DPPH IC50 15.92 μg/mL; ABTS IC50 41.85 μg/mL; FRAP IC50 39.9 μg/mL) compared to leaf methanol extract. Similarly, essential oil exhibited higher antidiabetic activity (in terms of α-amylase inhibitory capacity) (IC50 97.50 μg/mL) compared to methanol extract and lower antidiabetic activity in comparison to the standard (IC50 71.9 μg/mL). The anticancer activity of essential oil was found to be more effective against the PC-3 cell line (IC50 39.1 μg/mL) while leaf methanol extract was more effective against OVCAR-3 (IC50 47.5 μg/mL), MCF-7 (IC50 48.1 μg/mL), and h-1299 (IC50 45.9 μg/mL). C. excavata essential oil exhibited lower antimicrobial activity compared to leaf methanol extract. In summary, this study on the characterization of phytoconstituents and pharmacological activities of C. excavata leaf essential oil could be helpful in exploiting its therapeutic potential sustainably as well as the discovery of new lead molecules.