Surfactant carbohydrate analyses

An effort was made to better quantitate this suggested preponderance of N-acetylglucosamine and/or N-acetylgalactos-amine in the carbohydrate portion of microbubble glycopeptide surfactant by performing direct HPLC analysis of the monosaccharides contained in the surfactant. This analysis began with the (carbohydrate) hydrolysis of a partially purified preparation containing approximately 30 pg of the proteinaceous microbubble... 

Other fractions were prepared for carbohydrate analysis by hydrolysis (of the surfactants glycosidic bonds) in 2 N HC1 in sealed ampules for 6 hr at 100°C (ref. 331). Monosaccharide analyses were performed on a programmed Tracor 985 HPLC system employing a Bio-Rad HPX-87C cation-exchange column for monosaccharide separation. 

In polymer applications derivatives of oils and fats, such as epoxides, polyols and dimerizations products based on unsaturated fatty acids, are used as plastic additives or components for composites or polymers like polyamides and polyurethanes. In the lubricant sector oleochemically-based fatty acid esters have proved to be powerful alternatives to conventional mineral oil products. For home and personal care applications a wide range of products, such as surfactants, emulsifiers, emollients and waxes, based on vegetable oil derivatives has provided extraordinary performance benefits to the end-customer. Selected products, such as the anionic surfactant fatty alcohol sulfate have been investigated thoroughly with regard to their environmental impact compared with petrochemical based products by life-cycle analysis. Other product examples include carbohydrate-based surfactants as well as oleochemical based emulsifiers, waxes and emollients. 

To obtain data on the heterogeneity of the glycopeptide fraction of microbubble surfactant, comparative amino acid analyses were performed on two of the major peaks obtained from gel filtration. From the ratio of absorbances at 230 and 280 nm (ref. 265) and the elution profile shown in Fig. 5.3, it appeared that peaks I and III would differ the most in amino acid composition and, therefore, these two peaks were selected for amino acid analysis. Peak I was sufficiently large to be divided into three equal aliquots and peak III into two equal aliquots for automated analysis. Peak II, which eluted closest (Fig. 5.3) to the dominant peak I and presumably was most similar in molecular composition to this large initial peak, was analyzed separately by HPLC for carbohydrate content. 

In this chapter we introduce compounds which have been successfully applied in the construction of supramolecular assemblies. Only the amphiphiles which have been prepared in sufficient quantities have been admitted milligram quantities being considered unacceptable as starting materials for the preparation, analysis and application of assemblies. Experience proves that complicated dyes, pore builders, receptors etc. never reappear in the literature after their syntheses and spectroscopic properties have been reported. On the other hand, such easily attainable synkinons and surfactants around the ten gram scale need not, of course, be too simple. On the contrary, they may contain all the components of the chiral pool, i.e. amino acids, carbohydrates, steroids etc., as well as all commercial dyes of interest such as protoporphyrin, phthalo-cyanines, carotenes, viologen and quinones. 

Like ELSD, CAD has been applied for the analysis of nonvolatile neutral, acidic, basic, and zwitterionic compounds, both polar and nonpolar. Compound classes include amino acids, fatty acids, carbohydrates, lipids, proteins, steroids, surfactants, and other compounds with weak or no chromophores used in the pharmaceutical, food, chemical, and consumer products industries. Some applications involving ionic and polar species are described below. 

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