Thin Layer Chromatographic Determination of Neutral Lipids and Phospholipids in Biomphalaria Glabrata Snails Fed Lettuce Versus Hen's Egg Yolk as a Function of Time

Abstract

TLC on HP preadsorbent silica gel plates was used to determine, at various times over a 21-day period, neutral lipids and phospholipids in the plasma and digestive glandgonad complex (DGG) of Biomphalaria glabrata snails maintained on diets of leaf lettuce and hen's egg yolk. The DGG of yolk-fed snails showed considerable elevation of triacylglycerols by day 3, and free fatty acids and sterols by day 5. Hemolymph from two pools of yolk-fed snails was analyzed on day 7, and the respective results for free fatty acids, sterols, and triacylglycerols were 0.036, 0.0023, and 0.028 g/dL. Comparable values in lettuce-fed snails were 0.0061 for free fatty acids, 0.0016 for sterols, and triacylglycerols were not detected. Semiquantitative TLC showed that compared to lettuce-fed snails, the plasma of yolk-fed snails had elevations in sterols, free fatty acids, triacylglycerols, and phospholipids from days 5 to 21. The DGG of snails fed both diets showed approximately equal amounts of phosphatidylcholine and phosphatidylserine throughout the 21 days, but phosphatidylethanolamine was elevated in the DGG of yolk-fed snails by day 5. All phospholipid fractions were elevated in the plasma of yolk-fed snails during the 21-day period, with plasma from lettuce-fed snails showing only negligible amounts of phospholipids.