GC-MS analysis for the Determination of Chemical Constituents and Pharmacological Activities of Gum Karaya (Sterculia urens Roxb.,) Essential Oil

Abstract

Essential oils are produced by plants for many reasons including protection against various bacterial, fungal and viral infections. Numerous essential oils and their major constituents are known to exhibit promising pharmacological and antimicrobial activity and can therefore be a good source of biologically active molecules and/or fractions. It is generally accepted that a crude phytomedicine needs to be evaluated holistically and the research method best suited for this approach is metabolomics. In this study a non-targeted metabolomic approach was followed to explore the pharmacological and antimicrobial activity and chemistry of essential oil extracted from Gum Karaya (Sterculia urens Roxb.,). Essential oil was extracted by hydrodistillation and then analysed by gas chromatography coupled to mass spectrometry (GC–MS). The GC-MS analysis results confirms 30 compounds that accounted for 98.84 % of the oil, which included 6 compounds as major compounds. The major compounds identified in the essential oil are Diethyl Phthalate (37.57 %), 1,4,5,6-Tetrahydrocyclopentapyrazole-3-carboxylic acid, (1-adamantan -1-ylethylidene) hydrazide (19.83 %), 1,6-Octadien-3-ol, 3,7-dimethyl-,2-aminobenzoate (17.48 %), 1,3-Cyclopentadiene, 5,5-dimethyl- 2-propyl- (6.58 %), Bicyclo[2.2.1]heptane, 2-ethyliden-1,7,7-trimethyl-, (Z)- (4.28 %), and 1-Isopropenyl-3-propenylcyclopentane (4.55 %). Further the pharmacological activities such as DPPH free radical scavenging assay (antioxidant), α-amylase inhibition assay (anti-diabetic), albumin denaturation assay (anti-inflammatory) and well diffusion method (antibacterial) of the extracted essential oil was evaluated and found to be having high activity. Hence it can be concluded that the essential oil extracted from Karaya gum could be used as a source of natural antioxidant, antidiabetic, anti-inflammatory and antibacterial agents.