Conjugated linoleic acid (CLA). Cis 9, trans 11 and trans 10, cis 12 isomer detection in crude and refined corn oils by capillary GC


  • Özlem Tokuşoğlu Celal Bayar University, Akhisar M.Y.O.



Conjugated linoleic acid, Corn oil, GC, Isomer, Refining


Conjugated linoleic acids (CLAs) exhibit protective effects against various types of cancer and heart diseases. With the newly developed capillary gas chromatographic method (GC), cis9, trans11 and trans10, cis12 octadecadienoic acid isomers of CLA (C18:2) were determined in crude and refined corn oils as qualitative and quantitative measurements. Cis 9, trans11 C18:2 (c9, t11 CLA) was the major CLA isomer in both oils. It was found that c9, t11 CLA was 0.62% of the total lipid in crude oil and 1.24% of the total lipid in refined oil. Using the refining process, the total CLA was 1.38% whereas that of crude corn oil was 0.62%. An approximate 2.2 fold increase in the total CLA was found in refined oil (n = 9) (p < 0.01). The alteration in CLA could be used as a quality indicator for the refining process due to the contrubution of CLA to polyunsaturated fatty acids. Analytical method validation, calibration (R2 = 0.9999) and recovery data [y = 2.782x + 0.046 (R2 = 0.9999)] were performed (p < 0.01).The proponed chromatographic procedure could be used for vegetable oil quality control


Download data is not yet available.


Ackman RG, Eaton CA, Sipos JC, Crewe NF. 1981. Origin of cis-9, trans-11-octadecadienoic and trans-9, trans-11 octadecadienoic acids inthe depot fat of primates fed a diet rich in lard and corn-oil and implications for the human diet. Can. Inst. Food Sci.Technol. J. 14, 103-107.

Akalin AS, Tokuşoğlu Ö, Gönç S, Ökten S. 2005. Detection of Biologically Active Isomers of Conjugated Linoleic Acid in “Kaymak. Grasas Aceties 56 (4) 298-302.

Akalin AS, Tokuşoğlu Ö, Gonc S, Aycan 8. 2007. Occurrence of conjugated linoleic acid in probiotic yoghurts supplemented with fructooligosaccharide. Int. Dairy Journal. 17, 1089-1095. doi:10.1016/j.idairyj.2007.02.005

AOAC. 1999. Official methods of analysis of the Assocation of Official Analytical Chemists., Method Nº 92307, AOAC:Washington D.C.

Britton M, Fong C, Wickens D, Yudkin J. 1992. Diet as a source of phospholipid esterified 9,11-octadecadienoic acid in humans. Clin. Sci. 83, 97-101.

Chan Henry WS, Lewett G. 1977a. Autoxidation of methyl linoleate: separation and analysis of isomeric mixtures of methyl linoleate hydroperoxides and methyl hydroxylinoleates. Lipids 12 99-104. doi:10.1007/BF02532979

Chan Henry WS, Lewett G. 1977b. Autoxidation of methyl linoleate: analysis of methyl hydroxylinolenate isomers by high performance liquid chromatography. Lipids 12, 837-840. doi:10.1007/BF02533273

Chin SF, Liu W, Storkson JM, Ha YL, Pariza MW. 1992. Dietary sources of conjugated dienoic isomers of linoleic acid, a newly recognized class of anticarcinogens. J. Food Comp. Anal. 5, 185-197. doi:10.1016/0889-1575(92)90037-K

Evans ME, Brown JM, McIntosh MK. 2002. Isomerspecific effects of conjugated linoleic acid (CLA) on adiposity and lipid metabolism. J. Nutr. Biochem. 13, 508-516. doi:10.1016/S0955-2863(02)00211-5

Fogerty A, Ford G, Svoronos D. 1988. Octadeca-9,11- Dienoic Acid in Foodstuffs and in the Lipids of Human Blood and Breast Milk. Nutr. Reports Int. 38, 937-942.

Guo DD, Moon HS, Arote R, Seo JH, Quan JS, Choi YJ, Cho CS. 2007. Enhanced anticancer effect of conjugated linoleic acid by conjugation with Pluronic F127 on MCF-7 breast cancer cells. Cancer Lett. 254 (2) 244-254. doi:10.1016/j.canlet.2007.03.007

Ha YL, Grimm NK, Pariza MW. 1987. Anticarcinogens from fried Ground Beef: Heat-Altered Derivatives of Linoleic Acid. Carcinogenesis 8 (12) 1881-1887. doi:10.1093/carcin/8.12.1881

Hur SJ, Park Y. 2007.Effect of conjugated linoleic acid on bone formation and rheumatoid arthritis. (Review.) European J. Pharmacol. 568 (1-3) 16-24. doi:10.1016/j.ejphar.2007.04.056

Jung Mi Ok, Ju Jin Woo, Choi Dong Seong, Yoon Suk Hoo, Jung Mun Yhung. 2002. CLA formation in oils during hydrogenation process as affected by catalyst types, catalyst contents, hydrogen pressure, and oil species. J. Am. Oil Chem. Soc. 79 (5) 501-510. doi:10.1007/s11746-002-0512-8

Katzman MA, Jacobs L, Marcus M, Vermani M, Logan AC. 2007. Weight gain and psychiatric treatment: is there as role for green tea and conjugated linoleic acid? Lipids Health Dis. 6: 14. doi:10.1186/1476-511X-6-14

Kepler Carol R, Tucker WP, Tove S. B. 1971. Biohydrogenation of unsaturated fatty acids. V. Stereospecificity of proton addition and mechanism of action of linoleic acid Δ12-cis, Δ11-trans-isomerase from Butyrivibrio fibrisolvens. J. Biol. Chem. 246, 2765-2771.

Lin H, Boylston T, Chang M, Luedecke L, Shultz T. 1995. Survey of the conjugated linoleic acid contents of dairy products. J. Dairy Sci. 78 (11) 2358-2365.

Pakdeechanuan P, Intarapichet KO, Tongta S. 2007. Effect of Extrusion Parameters on Conjugated Linoleic Acids of Corn Extrudates J. Agric. Food Chem. 55 (4) 1463 -1468. doi:10.1021/jf0618426

Pariza MW. 1999. The biological activities of conjugated linoleic acid. Yuraweez MP, Mossoba MM, Kramer JKG, Pariza MW, Nelson GJ. 1999. (Ed.) Advances in Conjugated Linoleic Acid Research 1, 12-20. AOCS Press, Champaign, IL, USA.

Pariza MW, Park Y, Cook ME. 2001. The biologically active isomers of conjugated linoleic acid. Progress in Lipid Research 40, 283. doi:10.1016/S0163-7827(01)00008-X

Ricardo Uauy MD, Valenzula A. 2000. Marine oils: health benefits of n-3 fatty acids. Nutrition 16 (7/8) 680-684. doi:10.1016/S0899-9007(00)00326-9

Statistica.1998. Statistica for Windows, ’98 edition, Version 6.0, StatSoft Inc., Tulsa, OK, USA.

Thrush AB, Chabowski A, Heigenhauser GJ, McBride BW, Or-Rashid M, Dyck DJ. 2007. Conjugated linoleic acid increases skeletal muscle ceramide content and decreases insulin sensitivity in overweight, nondiabetic humans. Appl. Physiol. Nutr. Metab. 32 (3) 372–382. doi:10.1139/H06-116

Tokuşoğlu Ö. 2003. “Membrane Processes and Membran Filtration-Supercritical Extraction Systems in Food Technology” in Food Emulsions. Graduate Lecture Notes. Celal Bayar University, Manisa,Turkey.

Tokuşoğlu Ö, Ünal MK. 2003. Biomass Nutrient Profiles of three microalgae: Spirulina Platensis, Chlorella Vulgaris and Isochrisis Galbana. J. Food Sci. 68 (4) 1144-1148. doi:10.1111/j.1365-2621.2003.tb09615.x

Torres-Duerte AP, Vanderhoek JY. 2003. Conjugated linoleic acid exhibits stimulatory and inhibitory effects on prostanoid production in human endothelial cells and platelets. Biochimica et Biophysica Acta (BBA) / Molecular Cell Research 1640 (1) 69-76.

Watras AC, Buchholz AC, Close RN, Zhang Z, Schoeller DA. 2007. The role of conjugated linoleic acid in reducing body fat and preventing holiday weight gain. Internat. J. Obesity 31 (3) 481-487. doi:10.1038/sj.ijo.0803437




How to Cite

Tokuşoğlu Özlem. Conjugated linoleic acid (CLA). Cis 9, trans 11 and trans 10, cis 12 isomer detection in crude and refined corn oils by capillary GC. grasasaceites [Internet]. 2008Jun.30 [cited 2022Dec.10];59(2):146-51. Available from: