Peculiarities of Ultraviolet Absorption Spectra of Lamprey and Rat Brain Lipid Extracts and Their Correlation with Fatty Acid Composition

The ultraviolet (UV) absorption spectra of rat and lamprey brain lipid extracts have been studied. It was found that in both species the absorption of UV light took place, the shift of the absorption spectra to the more long-wave region being observed in the lamprey brain lipid extract. The established fact indicate the presence of oxidation products of lipids and their diene conjugates in the studied extracts, i.e., the appearance of the conjugated system of unsaturated bonds in the phospholipid molecules. The shift of the spectra to the more long-wave region in lampreys indicates a possible difference in the amount of polyenoic fatty acids in lamprey phospholipids. It was found that in lampreys it is predominantly the products of oxidation of phosphotidylcholine fatty acids, which shift the absorption spectrum to the more long-wave region. These are docosahexaenoic (C22:6 3), docosapentaenoic (C22:5 3), and eicosapentaenoic acids (C20:5 3). It is suggested that the membrane construction itself provides the basis for the energy accumulation.