Untersuchungen zur Modifizierung der Zellmembranlipide von Wolle durch industrielle Ausrüstungsprozesse

摘要

The aim of the present work was to examine, if wet processing of wool e.g. chlorination, chlorine/Hercosett treatment and reactive wool dyeing, generates modified lipids, which might contribute to skin irritation. Therefore, the composition of solvent extractable cell membrane lipids of industrially processed wool has been compared to that of raw white wool top. To assess possible modifications of the cell membrane lipids, several chromatographic techniques, mainly Thin-Layer Chromatography (TLC) and Gas-Liquid Chromatography with Mass Spectrometry coupling (GC/MS), have been used. In the cases where modified lipid components were detected in the solvent extractable lipids of industrially processed wool, the solubility of the modified lipid components in artificial sweat solutions was analyzed. Due to their amino function sphingolipids are possible targets for modification by reactive dyeing. However, since comparatively little is known about their chemical composition in wool, the sphingolipids were extracted from the wool by chloroform/methanol and characterized by GC/MS. As a consequence of the high oxidation potential of free chlorines, the chlorination treatment in the shrinkproofing process of wool leads mainly to the formation of hydroxy fatty acids, but not to the formation of chlorinated lipids. 9,10-Dihydroxy stearic acid represents the main part of the reaction products when the lipid reference oleic acids is subjected to chlorination. It was only detected in the ethanol-soluble lipids of the wool samples which had been chlorinated in model laboratory experiments, but not in the lipid fractions of wool samples with industrial chlorination or Hercosett-treatment TLC revealed that the lipid fractions of wool samples, which had been dyed with reactive dyestuff combinations (consisting of Lanasol, Remazol and Realan dyestuffs) contain UV active and coloured compounds. In one case a yellow component was detected which is directly derived from a dyestuff (Realan Golden yellow RC 84%), in another case a lipid compound modified by the applied dyestuffs was detected. GC/MS analyses of chloroform/methanol-soluble sphingolipids showed that the free ceramides of wool consist mainly of nonhydroxy acid (C16:0, C18:0, C20:0 C22:0, C24:0) amidified sphinganine- and sphingosine related ceramides. Sphinganine was found to be the main long-chain base in the free ceramides of wool. A similar composition for the long-chain bases is described in the in the literature for the ceramides of human hair. In contrast to the ceramides of human hair, the ceramide fraction of wool do not contain alpha-hydroxy fatty acids. To analyze the chloroform/methanol-soluble cerebrosides of wool by GC/MS the amide-linked fatty acids and the glycosidic carbohydrates were released by acid methanolysis. A methyl galactoside was determined to be present as the basic carbohydrate compound of the cerebrosides in wool. No major changes were observed in the qualitative composition of ceramides after dyeing of wool.