The Isolation and Partial Characterization of Gangliosides and Ceramide Polyhexosides from the Lens of the Human Eye

The first isolation of glycolipids from the lens of the human eye is described. Neutral (ceramide polyhexosides) and acidic (gangliosides) glycolipids were separated by column chromatography and further resolved by thin-layer chromatography. The components were methanolyzed, converted to trimethyl silyl ethers and the ratios of the components determined. Two types of monosialogangliosides were found. The most abundant ganglioside contained long chain base/fatty acid/glucose/galactose/neuraminic acid in the ratio 1/1/1/2/1. The ratio of components of the minor ganglioside fraction was 1/1/1/1/1. Dihydrosphingosine was the major base and the major fatty acids were palmitate and nervonate. The ceramide polyhexosides all had a glucose/galactose molor ratio of 1/1 and the mixture of ceramide polyhexosides had a dihydrosphingosine/sphingosine molar ratio of 7.85. The fatty acids ranged from C(10) to C(25) with both odd and even carbon chains and were saturated or monounsaturated with palmitate, oleate, and nervonate predominating.