Comparative Study of Fat body Lipid Alterations in White Grub adults of Leucopholis lepidophora and Oryctes rhinoceros

Abstract

The fat body plays major roles in the life of insects. It is a dynamic tissue involved in multiple metabolic functions. One of these functions is to store and release energy in response to the energy demands of the insect. Insects store energy reserves in the form of glycogen and triglycerides in the adipocytes, The neutral lipids (NL) and phospholipids (PL) with their constituents were studied in the fat body of male and female adults of Leucopholis lepidophora and Oryctes rhinoceros by employing thin layer chromatography (TLC) and bioassay technique. Comparatively O. rhinoceros exhibits more lipids than L.lepidophora. The quantity of neutral lipids in male and female fat bodies of former and later species was measured 30.12, 45.212 and 49.221. 63.894 mg/gm wet weight of tissues respectively. The phospholipid values in male and female fat bodies of former species were 20.663, 14.798 and 23.266, 17.349 mg/gm wet weight of tissues respectively. The NL: PL ratio in male and female adult fat bodies of former species was 2: I and 3:1 whereas in later species it becomes 2:1 and 4:1. This indicated that the neutral lipids were dominated over the phospholipids in both species. The neutral lipids found in six forms. Triacylglycerol was the main component, monoacylglycerol, diacylglycerol, cholesterol, was moderate and cholesterol ester and free fatty acids low in quantity. Phospholipids exhibited seven constituents; phosphatidyl-choline and phosphatidyl-ethanolamine high in concentration, Lysophosphatidyl-choline and sphingomyelin moderate in concentration, and phosphatidyl- inositol, phosphatidyl-serine and phosphatidic acid low in quantity.