Secondary Metabolites of the Cuticular Abdominal Glands of Variegated Grasshopper (Zonocerus variegatus L.)

Abstract

Chemical compounds were extracted with petroleum ether from the cuticular abdominal glands of grasshopper (Zonocerus variegatus L.) and eleven compounds were characterised using Gas Chromatography/Mass Spectrometry (GC/MS) technique in combination with Fourier Transform-Infrared Spectroscopy (FT-IR). The compounds analysed were 2,7-dimethyloctane (3.21%), decane (5.33%), undecane (3.81%), tridecanoic acid methyl ester (4.76%), hexadecanoic acid (9.37%), 11-octadecenoic acid methyl ester (23.18%), pentadecanoic acid, 14-methyl-methyl ester (4.43%), (Z)-13-docosenoic acid (10.71%), dodecyl pentafluoropropionate (9.52%), 2-dodecyl-1,3-propanediol (6.38%), and 1,12-tridecadiene (19.30%). FT-IR analysis of the extract showed peaks at 1270.17 (C–O and C–F), 1641.48 (C=C), 2937.68 (C–H), and 3430.51 (O–H) cm−1 indicating the presence of ether, alkene, alkane, alcohol, carboxylic acid, and fluoric compounds. These compounds consisted of 32.37% ester, 31.65% hydrocarbons, 20.08% fatty acid, 9.52% halogenated ester, and 6.38% alcohol. The highest component was 11-octadecenoic acid methyl ester followed by 1,12-tridecadiene. Since behavioural bioassays were not carried out, the consideration of these compounds to be pheromone semiochemicals remains a hypothesis.