[Free radicals formed during UV-irradiation of biological membrane lipids]

Formation of free radicals under UV-irradiation of egg phosphatidyl choline, and synthetic phosphatidyl cholines and their analogs, as well as of their model compounds was studied. When saturated fat lipids are UV-irradiated radicals--CH2CH2 are accumulated at the expense of the breakage of--CH2CH2--COOH-bond. Radicals CH3--OCH2, HCO are formed in aminoalcohols due to the breakage of --OCH2--CH2N+(CH3)3- and--CH2--N+(CH3)3-bonds. It has been found that in natural and synthetic phospholipids radicals are formed in the course of photochemical reactions in complex ether and amine groups. The mechanism of radical formation is discussed.