Identification of Secondary Metabolites from the Ethanol extract of the leaves of Bauhinia tomentosa by GC-MS Analysis

Abstract

Gas Chromatography-Mass Spectrometry (GC-MS) is normally used for direct analysis of chemical components existing in herbal medicines. The medicinal plants are having numerous bioactive components which are identified even at less than 1ng by using GC-MS or LC-MS analysis. The aim of this study is to identify the secondary metabolites present in the leaves of B. tomentosa using gas chromatography-mass spectrometry (GC-MS) analysis. In the present study the ethanol extract of the leaves of Bauhinia tomentosa has been subjected to GC-MS analysis, while the mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology (NIST) library. GC-MS analysis revealed the presence of 14 secondary metabolites. These compounds were identified by comparing their retention times and peak areas with those from the literature and by interpretation of the mass spectra. The major secondary metabolites were DL-.alpha.-tocopherol (14.84%), 2-[(trimethylsilyl oxy]-, methyl ester, 1-alpha,2-alpha.-epoxy-1-beta-methylcholesta-4,6-dien-3-one (12.93%), pentacosenoic acid (12.71%), phytol (10.28%), Ethyl Isoallocholate (8.197%), Spirost-8-en-11-one-3-hydroxy-,(3-beta,5 alpha,14 beta,20 beta, 22 beta,25R)-(8.162%), Urs-12-en-28-ol (6.675%), 1-Octadecyne (5.702%) and Cholest-8-en-3-beta-ol,Acetate (5.426%). The compounds having area less that 5% were considered of no significance. These findings suggest that the presence of these secondary metabolites may be the cause for the properties exhibited by Bauhinia tomentosa. Thus, presence of various bioactive compounds justifies the use of the leaf for various ailments by traditional practitioners.