STUDY OF SAMPLE PREPARATION OF SEED OILS WITH CONJUGATED FATTY ACIDS FOLLOWED BY HPLC

Abstract

Conjugated fatty acids have been shown to possess many valuable biological activities, including anticarcinogenic, antiatherogenic, anti-inflammatory, and antidiabetic effects and immune-modulating properties. However, these compounds are susceptible to external factors (temperature, light) and easily decomposed and oxidized during separation, extraction, and sample processing prior to analysis. In this work, a fast and efficient sample preparation procedure for analyzing triacylglycerol compositions containing conjugated fatty acids in seed oils was studied. The sample preparation procedure consists of three stages: the rapid determination of the presence of conjugated double fatty acids in seed oil using UV spectroscopy; solvent extraction of seed oil at room temperature; oil purification using solid phase extraction with silicagel as stationary phase. The results showed that the molecular absorption spectra of seed oil in n-hexanee in the wavelength range of 220-400 nm could be used to quickly detect the presence of fatty acid moieties, containing conjugated double bonds in oil. The seed oil was extracted at room temperature using three different solvents in polarity: n-hexane, dichloromethane, and acetone; and compared with the traditional Soxhlet extraction method. The seed oil was purified by solid phase extraction using silicagel as the stationary phase. The catalytic activity of silica gel with analytical compounds absorbed on the stationary phase of solid phase extraction columns was controlled and discussed.