Sex pheromone biosynthetic precursors in Bombyx mori

Abstract

In addition to the sex pheromone components (E,Z)-10,12- hexadecadienol , (E,E)-10,12- hexadecadienol , and (E,Z)-10,12- hexadecadienal , the sex pheromone gland of Bombyx mori produces glycerolipids containing (E,Z)-10,12- hexadecadienoate and (E,E)-10,12- hexadecadienoate . The methyl esters of these fatty acyl groups were identified on the basis of mass spectra, ozonolysis and comparison of gas-liquid chromatographic retention times with those of the corresponding synthetic compounds. (Z)-11- hexadecenoate was also present, in addition to the more common fatty acyl groups hexadecanoate, (Z)-9- hexadecenoate , octadecanoate, (Z)-9- octadecenoate , (Z,Z)-9,12- octadecadienoate and (Z,Z,Z)-9,12,15- octadecatrienoate . (E,Z)-10,12- hexadecadienoate and (Z)-11- hexadecenoate were the most abundant fatty acyl groups in the triacylglycerols, were less abundant in the choline phosphatides and ethanolamine phosphatides and were virtually absent from the diacylglycerols. Base methanolysis was used to convert fatty acyl groups to the corresponding methyl esters for identification. It was observed that acid methanolysis destroyed fatty acyl groups with conjugated double bonds, as well as the corresponding pheromone components. Non-conjugated fatty acyl groups in the gland formed methyl esters equally well by base methanolysis or acid methanolysis.