Analytical characterization of fatty acids assignment

Quantification results of fatty acid methyl esters # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Name C6: 0; Hexanoic acid, methyl ester C8: 0; Caprylic acid, methyl ester C10: 0; Capric acid, methyl ester C12: 0; Lauric acid, methyl ester C14: 0; Myristic acid, methyl ester C15: 0; Pentadecanoic acid, methyl ester C16: 0; Palmitic acid, methyl ester C16: 1c; Palmitoleic acid, methyl ester C17: 0; Margaric acid, methyl ester C18: 0; Stearic acid, methyl ester C18: 1c; Oleic acid, methyl ester C18: 1n8T; Octadecanoic acid, methyl ester C18: 2c; Linoleic acid, methyl ester C20: 0; Arachidic acid, methyl ester C20: 2; Eicosadienoic acid, methyl ester Retention time (min. ) 3. 060 4. 957 6. 796 8. 552 11. 000 12. 670 14. 692 15. 213 16. 985 19. 704 20. 266 20. 433 21. 912 27. 306 29. 756 AreaO 19654 11442 3454 2928 39973 2407 2674581 8191 13220 427823 816146 86541 1554375 30982 22200 Conc. (%)O 0. 16 0. 11 0. 02 0. 1 0. 18 0. 01 6. 59 0. 21 0. 09 1. 35 5. 41 0. 92 16. 22 0. 22 0. 65 Std. Dev. * 0. 002 0. 003 0. 002 0. 003 0. 010 0. 003 0. 020 0. 002 0. 003 0. 010 0. 003 0. 004 0. 002 0. 004 0. 005 * Standard deviation values for the three measurement results; O Average of three measurement results. with R2 value less than 0. 99 (R2 > 0. 99) in each case. Fig. 1 shows the GC-MS chromatogram obtained from fatty acid standard mixture of 37 components while Fig. 2 is the GCMS chromatogram of Datura alba seed oil with properly labeled signals of analytes detected. Both the saturated and unsaturated fatty acids were found in the sample under investigations.

Linoleic acid was found in highest concentration which is necessary for the maintenance of growth. It has been shown to be a potent inhibitor of cyclooxiginase-2 (COX-2) catalyzed prostaglandin biosynthesis. 29, 30 Among the other fatty acids with concentrations more than 1% are: Palmitic acid (6. 59%), Oleic acid (5. 41%) and Stearic acid (1. 35%) were found. Amount of rest of the fatty acids were less than 1% (Table 1). From the results it is clear that Datura alba seeds, besides its toxicity, can also be used in various pharmaceutical products as it contains different bioactive compounds like fatty acids. The method applied is a reliable method of analyzing imultaneously many fatty acid components in a single run. 3. EXPERIMENTAL 3. 1. Chemicals and reagents Boron triflouride solution in methanol (10%) was purchased from Fluka Chemie (Buchs, Switzerland). Sodium hydroxide solution (methanolic; 0. 5 N) and sodium chloride (analytical grade) were obtained from Merck (Darmstadt, Germany) while methanol (HPLC grade), n-hexane (HPLC grade) were from Fischer Scientific (Leicestershire, UK). Helium gas (99. 9999%) from Pak gas (United Arab Emirates) was procured. Tridecanoic acid methyl ester and Fatty acid methyl esters (FAMEs) 37 components standard mix were obtained from AccuStandard (Newhaven, Connecticut USA).