Resumen de Conjugated linoleic acid (CLA). Cis 9, trans 11 and trans 10, cis 12 isomer detection in crude and refined corn oils by capillary GC
- español
El ácido linoleico conjugado (CLA) parece exhibir efecto protector frente a enfermedades cardiovasculares y varios tipos de cáncer. En este trabajo, se establece un mátodo analítico mediante cromatografía de gases con columna capilar para la determinación cualitativa y cuantitativa de los isómeros cis 9,trans 11 y trans 10, cis 12 en aceites de maiz crudo y refinado. El isómero cis 9, trans11 C18:2 fue el mayoritario encontrándose en concentraciones de 0.62% en el aceite cru,do y de 1.24 % en el aceite refinado. La cantidad total de CLA encontrada en el aceite refinado (n = 9) (p < 0.01) fue superior al doble de la encontrada en el aceite crudo. Se realiza la validación del método analítico, aportándose datos de calibración (R^2 = 0.9999) y de recuperación [y = 2.782x+0.046 (R^2 = 0.9999)]. El método cromatográfico propuesto podría ser usado para el control de calidad de los aceites vegetales.
- English
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.
