The lipids of the common house cricket,Acheta domesticus L. III. Sterols

Abstract

Sterols constitute 1.95% of the total extractable lipids ofAcheta domesticus L., of which 18% are esterified. The free sterols consist of cholestane-3beta-ol (0.5%), Delta(5)-cholestene-3beta-ol (83.5%), Delta(7)-cholestene-3beta-ol (2.3%) Delta(5,7)-cholestadiene-3beta-ol (3%), Delta(5,22)-cholestadiene-3beta-ol (4%), Delta(5,7,22)-cholestatriene-3beta-ol (0.2%), campestane-3beta-ol (0.03%), Delta(5)-campestene-3beta-ol (1.0%), Delta(7)-campestene-3beta-ol (trace), Delta(5,7)-campestadiene-3beta-ol (0.2%), stigmastane-3beta-ol (0.09%), Delta(5)-stigmastene-3beta-ol (2.1%), Delta(7)-stigmastene-3beta-ol (0.04%), Delta(5,7)-stigmastadiene-3beta-ol (0.4%), Delta(5,22)-stigmastadiene-3betaol (0.1%). The same sterols are present in the esterified sterol fraction. Delta(7)-Sterols and Delta(5,7)-sterols are present in significantly larger amounts in the esterified fraction than in the free sterol fraction. By a comparison with the sterols of the cricket food, it is clear thatA. domesticus is capable of removing methyl and ethyl groups from C-24 of sterols of the campestane and stigmastane type. The ability to introduce a Delta(7) double bond into saturated and Delta(5)-sterols is indicated, and it is suggested that Delta(7)-sterols of the C(27), C(28), and C(29) sterol series may be intermediates in the conversion of Delta(5)-sterols to Delta(5,7)-sterols.

The lipidome of an omnivorous insect responds to diet composition and social environment

“…In this insect species, the total lipid content accounts for 10% of the dry weight (Udomsil et al, 2019) and 5–7% of the fresh weight (Gutiérrez, Fresch, et al, 2020) of the body composition. To the extent of our knowledge, studies on the lipidome of A. domesticus have mainly addressed general lipid composition in a descriptive way (Grapes et al, 1989; Hutchins & Martin, 1968; Lambremont & Dial, 1980; Martin & Carls, 1968; Wang & Patton, 1969) and developmental changes in some lipid categories and classes (Cripps et al, 1988; Cripps & De Renobales, 1988). However, no attempt has been made to examine the changes in the lipid profile induced by distinct diets and social environments in the house cricket A. domesticus .…”