Quantitative estimation of esters by thin‐layer chromatography

Abstract

A method for the analysis of fatty esters employing separation by thin-layer ehromatography and quantitative determination vitl their hydroxamie acids has been developed. Esters of different types are separated on silica gel plates, the spots or zones are scraped from the plates, the esters are extraeted from the silica gel, and the iron hydroxamie aeid complexes are formed. The latter are then measured by eolorimetry.The method is suitable for analysis of mixtures of ordinary, epoxy, monohydroxy, and dihydroxy fatty esters as well as for mixtures of mono-, di-, and triglyeerides.Used in conjunction with gas chromatography this method permits the fatty acid composition of seed oils containing oxygenated fatty acids to be measured in about 3 hours. The amount required for the total analysis is 1 to 10 rag. per determination, depending upon composition.

Comparative chemical composition of different muscle zones in angler (Lophius piscatorius)

“…Once the TAG fraction was purified, the method of Vioque and Holman (1962) was used to measure the ester linkage content according to the conversion of the esters into hydroxamic acids and subsequent complexion with Fe (III). Results were calculated as g TAG kg À1 muscle and as g TAG kg À1 total lipids.…”

Seasonal study of the lipid composition in different tissues of the common octopus ( Octopus vulgaris )

“…Once the TG were purified, the method of Vioque and Holman [27] was used for measuring the ester linkage content, according to their conversion into hydroxamic acids and further complexion with Fe(III). The results were expressed as g TG/100 g wet tissue.…”

“…1) was studied in both the ovary tissue and digestive gland. Muscle tissues were not considered at this point due to the low TG values determined (,0.005 g/100 g wet tissue) and to the relatively low sensitivity of the analytical method applied in this study [27]. According to its role as a storage lipid class [5,6], TG exhibited higher concentrations in the digestive gland than in the ovary tissue throughout the whole year.…”

Comparative Effects of Feeding Different Fats on Fatty Acid Composition of Major Individual Phospholipids of Rat Hearts

“…Quantification of the different classes of lipids was carried out separately by thin-layer chromatography using as developer hexane/ethyl ether/acetic acid (80:20:1). After develop ment, the bands corresponding to free cholesterol, tri glycerides, nonesterified fatty acid (NEFA) and cho lesterol esters were scraped off and quantified using the method of Vioque-Holman [20]. The phospholip ids were scraped off and eluted from the silicagel with chloroform/methanol (2:1 v/v) and put on a new chro matography plate, developed with a mixture of chloroform/acetone/water (75:25:4).…”