Polyunsaturated fatty acids biosynthesis in modicogryllus truncatus (Tarbinsky, 1940) (Orthoptera: Gryllidae)

In this study, C18 polyunsaturated fatty acids such as linoleic, linolenic acids andeicosanoids precusors C20 polyunsaturated fatty acids such as eicosatrienoic,eicosatetraenoic and eicosapentaenoic acids biosynthesis in M. truncatus(Orthoptera:Gryllidae) were investigated.For this, nymphs were reared separately on three different diets such as stockculture medium containing lettuce, fat-free artifical diet and artifical diet containingwheat germ oil until to adult.The phospholipid and triacylglycerol fatty acid composition of one-day old adultmale and female M. tuncatus reared on three different diets were analysed separately bygas chromatography-mass spectrometryThe analysis of fatty acid composition of insects showed that palmitic, oleic andlinoleic acids were found to be major fatty acids in phospholipid and triacylglicerolfractions.In addition, our analysis showed that presence of odd-chain fatty acids such aspentadecanoic (15:0) and heptadecanoic (17:0) acids. Trace amounts of linolenic andeicosanoid precusors C20 polyunsaturated fatty acids such as eicosatetraenoic andeicosapentaenoic acids were detected in both fractions.According to our results, de novo biosynthesis of linoleic (18:2n-6), linolenic(18:3n-3), eicosatetraenoic (20:4n-6) and eicosapentaenoic (20:5n-3) acids andelongation-desaturation of eicosatetraenoic acid (20:4n-6) in M. truncatus weredemonstrated.