Authors:G. E. Milkereit, S. S. H. Gerber, Karin Jankowski, A. Terjung, R. R. Schmidt, and V. Vill
A set of Y-shaped and Siamese-twin shaped carbohydrate based glycolipids was investigated using polarising microscopy. The structure was changed from the normal type (1 head, two chains) to complex inverted structures (2 heads outside 1 to 3 chains in the middle part). The carbohydrate headgroup was changed from mono- to disaccharide; also the alkyl chain length was varied systematically. The compounds displayed different thermotropic mesophases (Smectic A phases, columnar phases and cubic phases) depending on the type of carbohydrate headgroup and the alkyl chain length.
Authors:V. M. Garamus, G. E. Milkereit, Regine Willumeit, and V. Vill
In this work, we investigated the lyotropic aggregation behaviour in dilute solutions of two synthetic glycolipids with same alkyl chain. The chemical structure of the carbohydrate headgroups is similar, nevertheless as reported the thermotropic phase behaviour is different. We found that the slightly tilted compound showing a complex thermotropic phase behaviour forms large aggregates with substructure already in dilute solutions and the significantly tilted compound with its simple thermotropic phase behaviour forms small spherical micelles near the CMC.
The lipid profiles of brain from 10- and 18-day-old chick embryo, 1-day-old chick, and adult chicken as well as of full-term fetus rat, 21-day-old male, young adult male, and pregnant female rats were analyzed by thin-layer chromatography and densitometry. The emphasis was on the major glycolipids of brain during myelination (i.e., galactocyl diglyceride (GDG) normal fatty acid and hydroxyl fatty acid ceramide monohexosides (n-CMH, h-CMH, respectively)), and sulfatides (S) as well as the choline lipids sphingomyelin (SM), phosphatidyl choline (PC) and the two species of phosphatidyl ethanolamine plasmalogen (PE1 and PE2).Ten-day-old chick embryo brain revealed a low concentration of glycolipids, which increased gradually during development, and reached the highest level in the adult chicken brain. Rat brain did not begin to show the presence of these glycolipids until 21 days old. In addition, PE (i.e., PE1 and PE2) was shown to be the only alkenyle phospholipid in all samples analyzed. PE2 was shown to correlate with the myelination process. PC and SM were also present. SM concentration was very low in 1-day-old chick and 21-day-old rat brains and increased gradually, reaching its highest level in the adult chicken and rat brains.
. Miyazaki, J.-i. Yoshida*.
“ A photoflow reactor for the continuous photoredox-mediated synthesis of C-glycoamino acids and C-glycolipids ” R. S. Andrews , J. J. Becker , M. R. Gagne * Angewandte Chemie International Edition