REVERSED-PHASE LIQUID-CHROMATOGRAPHIC SEPARATION OF JUVENILE-HORMONE AND ITS METABOLITES, AND ITS APPLICATION FOR AN INVIVO JUVENILE-HORMONE CATABOLISM STUDY IN MANDUCA-SEXTA

A convenient reversed-phase liquid chromatographic method was developed to separate juvenile hormone (JH) and its metabolites. The known metabolites including JH acid, JH diol, and JH acid-diol, as well as an unknown metabolite, were efficiently separated within 25 min on a 50 × 4.6 mm polymer column using a linear gradient of acetonitrile:5 mm Hepes (pH 7.4) buffer. Use of the polymer column diminished tailing observed for the diol metabolite on a C18 silica column, and allowed use of slightly basic buffers without concern of column instability. Use of buffer was essential to give good peak shape and reproducible retention behavior for the acidic metabolites. Using this method, an in vivo JH catabolism study was performed in fifth stadium larvae of Manduca sexta. Injected (10R)-[3H]JH III was rapidly converted to JH acid-diol and to an unknown compound(s) indicating that, in addition to JH esterase, epoxide hydrolase and other reactions play an important role in the catabolism of JH. © 1990.