Refined cottonseed oil enjoys widespread applications in the food and chemical industries. Although the major lipids comprising cottonseed oil (triacylglycerols) are well known, there are many diverse lipid species in cotton seeds that occur at much lower levels and have important nutritional or anti-nutritional properties. Utilizing a single chromatographic technique for the separation of complex lipids lacks feasibility due to the diversity of lipid polarity and the large range of concentrations of lipid species in biological samples. In this study, ultra performance convergence chromatography (UPC2) was investigated for the separation of neutral and polar lipids in cottonseed extract. The method was initially developed using lipid standard mixtures and then applied for the analysis of cottonseed extracts.
The lipid technical samples were prepared in chloroform. The biological samples were extracted using a mixture of chloroform:methanol (2/1). The data was collected using high and low collision energy simultaneous data collection on a time of flight MS which allowed the characterization of lipids by precursor and product ion alignment. The chromatography is flexible and can be altered to provided greater retention; and with many occasions, greater specificity of intra-class separation for the neutral lipids. In terms of an analytical technique perspective, the elution mechanisms are conceptually similar to performing a mobile phase gradient elution profile by liquid chromatography. The comprehensive profile was used to screen seed lipid extracts from several cotton genotypes using multivariate statistical analysis. Potential markers that discriminate the different genotypes were identified and these markers of interest were quantified using targeted analysis.