A chemotaxonomic approach to fatty acid composition of the genera Helochares and Coelostoma (Coleoptera: Hydrophilidae)

Abstract

In this study, total lipid and fatty acid composition of insects belonging to the genera Helochares and Coelostoma (Coelostoma orbiculare Fabricius, 1775; Coelostoma transcaspicum Reitter, 1906; Helochares obscurus Muller, 1776; Helochares liyidus Forster, 1771) of Hydrophilidae (Coleoptera) family collected from Bingol Province were determined. Specimens were collected in 2015. Fatty acid component of the insects was determined by mass-gas chromatography (GC-MS). Total saturated fatty acids (Sigma SFA) were between 23.9-40.8%, total monounsaturated fatty acids (Sigma MUFA) were 21.6-53.2% and total polyunsaturated fatty acids (Sigma PUFA) were 14.3-27.4%. Myristic acid (14:0), pentadecanoic acid (15:0) palmitic acid (16:0), heptadecanoic acid (17:0) from SFA, palmitoleic acid (16:1n-7), oleic acid (18:1n-9) from MUFA; linoleic acid (18:2n-6), linolenic acid (18:3n-3), arachidonic acid (ARA, 20: 4n-6), eicosapentaenoic acid (EPA, 20: 5n-3) were the most important fatty acids. ANOSIM results showed that only the difference among the species was significant (R=0.63); the difference among subfamilies (R=0.17) and among the genera (R=0.17) and that the difference among the families (R=0.08) was not significant.