Analysis of Flavonoids and Essential Oils from Clausena Excavata and Their Medicinal Properties

This study was conducted mainly to determine the major flavonoid compounds and the composition of essential oils predominant in Clausena excavata, and also to examine its antioxidant, antibacterial and anticancer activities. The dried yields of C. excavata’s leaf crude extracts were also determined and methanol was found to be the best solvent for extracting soluble bioactive compounds from the leaves of C. excavata. Total phenolic contents were found abundantly in methanol crude extract of leaves. In the high performance liquid chromatography (HPLC) analysis, rutin and naringin were found predominant in the leaves of C. excavata, while in the gas chromatography-mass spectrometry (GC-MS) analysis, the major chemical components identified in the fruit oil were α-ocimene and terpinolene. Terpinolene was also being the main component and remarkably present in the leaf oil. Both of the fruit and leaf oils extracted with dichloromethane in the simultaneous distillation extraction (SDE) method were indicated in very low yield (less than 0.1%). Antioxidant activities of various crude extracts of Clausena excavata leaves were dependent on the amount of total phenolics present in the crude extracts. Inhibition of lipid peroxidation and free radical scavenger potential of those crude extracts closely dependent on the particular substitution pattern of free hydroxyl groups on the flavonoid skeleton. Antioxidant activity of methanol crude leaf’s extract was found greater than α-tocopherol in the ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods as well. The increase in the concentration of methanol crude leaf extract from 200 to 1000 μg/ml had increased its antioxidant activity. However, methanol crude leaf’s extract exhibited weak scavenging activity towards 1,1- diphenyl-2-picrylhydrazyl (DPPH) free radical. As for the determination of antibacterial activity in both of the disc diffusion and microdilution methods, the growth of all tested gram-positive bacteria, especially Micrococcus luteus was found effectively affected by the methanol crude leaf extract. Almost all of the crude extracts were active towards Micrococcus luteus. Fruit and leaf oil exhibited their effects on all tested gram-positive bacteria and certain gram-negative bacteria but those tested bacteria strains were just weakly inhibited. Antioxidant activity of flavonoids was associated with anticancer properties. In the MTT assay, however, fruit oil showed better cytotoxic activity than that in methanol crude leaf extract against MCF-7 cells. This implied that C. excavata fruit oil might be a good source for the breast cancer treatment due to the presence of possible active anticancer agents