title: The ecdysteroids from the tobacco hornworm during pupal-adult development five days after peak titer of molting hormone activity.
abstract: Six naturally occurring C27 ecdysteroids were isolated and identified from the tobacco hornworm during pupal-adult development five days after peak titer of molting hormone activity. In order of decreasing quantities the hormones were: 20,26-dihydroxyecdysone, 3-epi-20-hydroxyecdysone, 20hydroxyecdysone, 3-epi-20,26-dihydroxyecdysone, 3-epi-ecdysone, and ecdysone. 20-Hydroxyecdysone, in an earlier study, was the major molting hormone present at peak titer during pupal-adult development. The major ecdysteroid present during embryonic development in this insect, 26-hydroxyecdysone, was not detected. The copresence of all six of these ecdysteroids from a single developmental stage of an insect provides information on the metabolic interrelationships that exist among these steroids and on their possible function(s) in insects. The 3alpha-ecdysteroids were far less active than the 3 beta-epimers in the house fly assay. The significance of epimerization is discussed.
mesh_terms: D000818:Animals; D002845:Chromatography; D004440:Ecdysone / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000378:metabolism; D007915:Lepidoptera / Q000254:growth & development / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D011679:Pupa / Q000378:metabolism
chemical_list: D004440:Ecdysone