In this study, a method for determination of six phytosterols by gas chromatography-mass spectrometry with derivatization in vegetable oils was validated. The samples were hydrolyzed in an alkaline media at 70°C for 60 min. Then, the samples were performed liquid-liquid extraction with toluene. The phytosterols are derivatized to trimethylsilyl ethers and then analyzed by gas chromatography-mass spectrometry. The limit of detection and limit of quantification was 5 and 15 mg/kg, respectively. Recoveries of six phytosterols were between 93.5% and 101%.
GC-MS, phytosterols, vegetable oils
[1]. M. J. Lerma-Garcia, E. F. Simo-Alfonso, A. Mendez, J. L. Liberia and Jose Manuel Herrero-Marinez, “Fast separation and determination of sterols in vegetable oil by ultraperformance liquid chromatography with atmospheric pressure chemical ionization mass spectrometry detection”, Journal of Agriculture and Food Chemistry, vol. 58, p. 2771-2776, 2010.
[2]. I. Borkovcava, E. Janouskova, M. Drackova, B. Janstove and L. Vorlova, "Determination of sterols in dairy products and vegetable fats by HPLC and GC methods", Czech Journal of Food Science, vol. 27, 2008.
[3]. AOAC Official Methods of Analysis, Appendix F: Guidelines for standard method performance requirements. 2012.
[4]. AOAC Official methods 2007.03, “Campesterol, Stigmaterol, and beta-sitosterol in saw palmetto raw materials and dietary supplements”, 2007.
[5]. Y-Z. Chen, S-Y. Kao, H-C. Jian, Y. Yu, J-Y. Li, W-H Wang and C-W. Tsai, “Determination of cholesterol and four phytosterols in food without derivatization by gas chromatography-tandem mass spectrometry”, Journal of Food and Drug Analysis, vol 23, no.4, pp.1-9, 2015.
[6]. Ruinan Yang, Li Xue, Liangxiao Zhang, Xuefang Wang, Xin Qi, Jun Jiang, Li Yu, Xiupin Wang, Wen Zhang, Qi Zhang and Peiwu Li, “ Phytosterol contents of edible oils and their contributions to extimated phytosterol intake in the Chinese diet”, Foods, vol. 8, no. 334, pp. 2-12, 2019.
[7]. S.L. Abidi, “Chromatographic analysis of plant sterols in foods and vegetable oils”, Journal of Chromatography A, vo. 935, pp. 173-201, 2001.
[8. B. Xu, S. You, L. Zhou, H. Kang, D. Luo, H. Ma and S. Han, “Simultaneous determination of free phytosterols and tocopherols in vegetable oils by an improved SPE-GC-FID method”, Food Ananlytical Methods, vol. 13, no.2, pp. 1-12, 2020.
[9]. N. Qi, Y. Liu, L. Liao, X. Gong and C. Yang, “A new method for determination of campesterol, stigmaterol and β-sitosterol in edible oils by suprcritical fluid chromatography”, Journal of Food and Nutrition Reseach, vol.58, no. 4, pp. 363-369, 2019.