Journal of the Chinese Chemical Society, 2011, 58, 236-240
Analytical Characterization of Fatty Acids Composition of Datura alba Seed Oil by Gas Chromatography Mass Spectrometry Muhammad Nasimullah Qureshi,* Muhammad Siddique, Inayat-ur-Rahman and Farina Kanwal Medicinal Botanic Centre, PCSIR Laboratories Complex Peshawar, Pakistan Received July 9, 2010; Accepted November 23, 2010; Published Online December 14, 2010
Methyl ester derivatives of fatty acids were analyzed for the determination of the constituents of Datura seed oil. Gas chromatography coupled to mass spectrometer was used for these analyses. Results delivered that there were saturated as well as unsaturated fatty acids in Datura alba seed oil. Total of 15 different fatty acid components were identified and quantified. Methyl linoleate was found in highest concentration (16.22%) among the identified analytes of interest. In addition methyl esters of Palmitic acid (6.59%), Oleic acid (5.41%) and Stearic acid (1.35%) were found. Concentrations of rest of the detected fatty acids were less than 1%. From the literature it appears that no such work has been performed for the determination of fatty acids in Datura alba seed oil. Keywords: Datura alba; Fatty acids; Methylation; GC-MS.
1. INTRODUCTION Datura alba (Family; Solanaccae) grows in warmer parts of the world particularly in south and south east Asia including Pakistan, India and Sri Lanka. This annual herb is bushy, smooth, fetid, 0.5 to 1.2 m in height also attaining 6 feet or more in rich soils. The leaves are 18 cm long and the flowers are white in colour.1,2 Besides its familiarity for toxicity and poisoning,3 it has uses for a number of diseases like asthma, muscle spasm, whooping cough, skin ulcer, hemorrhoids, anti-rheumatic etc. Its oil based preparation is used for healing of all types of wounds in Ayurveda and Siddha practice of medicine since long ago.4 Datura species produces a number of small seeds encapsulated in an apple like fruit capsule; hence the name “thornapple” is based on this fact. The most common and medicinally important tropane alkaloids such as hyoscyamine, atropine and scopolamine have been isolated from Datura species. Clarification of the dual effect of this plant requires extensive research for the exploration of chemistry and pharmacology of the plant under investigation. The present work is a part of these investigations focusing on the determination of fatty acids in oil extracted from Datura seeds. Due to biological importance5,6 fatty acids have gained importance in food nutrition evaluation7-10 and in the diagnosis of certain diseases and pharmacology.11 Fatty acids
with unsaturation, either monounsaturated or polyunsaturated, have been used in lowering the risks of heart disease, against inflammation and in enhancing the immunity or immune system.12-17 A number of analytical techniques have been applied for the determination of fatty acids. These include: enzymatic, spectrophotometric, HPLC18-20 and gas chromatography (GC). 21-23 GC-MS is the method of choice for the analysis of fatty acids due to various reasons like speed, resolutions and sensitivity.24,25 From the literature it appears that most of the research work performed is the determination of alkaloids which are main constituents of this genus. No remarkable work has been carried out for the determination of fatty acids in Datura alba seed oil which is needed in order to explore its pharmacological importance. 2. RESULTS AND DISCUSSION Table 1 summarizes the results obtained from the GCMS analysis showing the relative concentration of individual esterified fatty acids based on the external standard method and the standard deviation values among the three results in each case. Analyses were performed three times and the values of area and concentration in Table 1 are the average of three measurement results. Quantification of FAMEs was performed using three points calibration curve