Effects of Various Diets on the Total Lipid Compositions of the Black Cricket Melanogryllus desertus Pall.

Authors: Mehmet BAŞHAN

Abstract: Fatty acid compositon of whole-body lipids in one-day old adult males and females of the black cricket, Melanogryllus desertus (Orthoptera: Gryllidae), and of its three different diets, were analyzed with gas chromatographic technicques to determine whether fatty acid profiles of the insect vary with its diets. The two artificial diets were based on casein, while the stock-culture medium was based on natural foods. The major components of the three diets and insects reared on these diets included the usual C16 and C18 saturated and unsaturated fatty acids, which are expected to be present in plant and insect lipids. Unfractionated total fatty acid composition of both sexes reared on the diets were not completely different. Their major fatty acids were oleic (47-53%), palmitic (20-25%) and linoleic acids (13-25%). Stearic (2-5%), myristic (2-4%), palmitoleic (<1-2%) and lauric acids (<1-2%) were also present in smaller amounts. The fatty acid compositon of the cricket lipids reflects but is not identical quantitatively to the fatty acid composition of the dietary lipids. Linoleic acid (C18:2n-6), which is an essential fatty acid for many insects, was also determined in adults of both sexes maintained on fat-free artificial diet for 4 months. It was concluded that M. desertus can synthesize linoleic acid.

Keywords: Diet, Total Lipid Composition, Melanogryllus desertus