Improved procedures for the isolation of pure oleic, linoleic, and linolenic acids or their methyl esters from natural sources

Abstract

The methods normally employed for the isolation of pure methyl oleate, linoleate, and a-linolenate from appropriate natural sources are reviewed and simple procedures for isolating these esters are recommended. Evening Primrose Oil (Oenotheru biennis) is a particularly useful source of linoleic acid.

Preparation of conjugated linoleic acid from safflower oil

“…Safflower oil was saponified and saturated, and monounsaturated fatty acids were removed as described by Gunstone et al (9). LA extracted from safflower oil (100 g) was crystallized in urea (120 g) dissolved in warmed MeOH (240 mL; 1 g/2 mL).…”

“…Additional LA was recovered from the urea adduct fraction (9). Adduct material was dissolved in minimal warm ddH 2 O with stirring.…”

The purification of fatty acid methyl esters by high pressure liquid chromatography

“…Procedures for preparing methyl esters from fatty acids or directly from glycerides have been reported previously (9). Transesterified oils containing unwanted polar oxygenated material were purified by elution from a short column of silica (sorbsil) with petroleum ether.…”

Technological challenges to assess n-3 polyunsaturated fatty acids from marine oils for nutritional and pharmacological use

“…Due to high cost, however, these methods are most suitable for small-scale laboratory preparation of purified samples rather than to the processing of large amounts of fish oil. Techniques suitable for smallscale preparation of EPA and DHA concentrates include controlled winterization (Gunstone et al 1976), urea adduct fractionation (Wright et al 1987), and silver resin chromatography (Adiof & Emken, 1985). Controlled winterization of the methyl or ethyl ester of the triglycerides is a low cost technique but provides low concentrations for each fatty acid ).…”