Effects of urban discharge on lipid and fatty acid composition of Diplodon chilensis

YUSSOPPONE, M.S; PASQUEVICH, M.Y.; HERAS, H.; LUQUET, C.M.; RIOS DE MOLINA, M.C.; ROCHETTA, I.

Potrero de los Funes

Congreso; XLVII Reunión SAIByBM; 2011

SAIByBM

The mussel Diplodon chilensis is abundant in lakes and rivers from Patagonia and it is considered as a potential bioremediation tool, reducing coliform bacteria from domiciliary wells. We evaluate changes in their lipid and fatty acid composition, by TLC and GC, on control and urban discharge polluted sites. Oxidative stress parameters were determined (antioxidant enzymes, GSH, lipid and protein oxidation) as well as glycogen and lipofuxin contents. The neutral/polar lipid ratio was higher in organisms come from the polluted area due to an increase in DAG and TAG and a decrease in PE. Polar lipids were the most affected, displaying higher amount of saturated FA (C18:0) and a decrease in the unsaturated FA, n3 and n6 (C16:1n7, C20:4n6, C21:5n3, C22:3n6). Lipid oxidation levels and lipofuxins were higher in bivalves from the polluted area, showing higher GSH levels and lower glycogen content. No changes were observed in antioxidant enzyme activities. These results demonstrate that a chronic exposure to urban effluent produces in D. chilensis an increase in GSH level, which is not enough to counteract the oxidative damage to lipids, especially to the polar ones and their PUFA. This last would indicate changes in the membrane permeability, being capable of maintaining storage lipid levels, probably at the expense of the glycogen consumption.