ISSN:
0739-4462
Keywords:
ecdysteroids
;
development
;
Chemistry
;
Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
Ecdysone metabolism in Pieris brassicae during the feeding last larval stage was investigated by using 3H-labeled ecdysteroid injections followed by high-performance liquid chromatographic (HPLCAbbreviations: 3DE = 3-dehydroecdysone; 3D20E = 3-dehydro-20-hydroxyecdysone; 2026E = 20,26-dihydroxyecdysone; E = ecdysone; Eoic = ecdysonoic acid; 2026E′ = 3-epi-20,26-dihydroxyecdysone; E′ = 3-epiecdysone; E′oic = 3-epiecdysonoic acid; E′8P = 3-epiecdysone 3-phosphate; 20E′ = 3-epi-20-hydroxyecdysone; 20E′3P = 3-epi-20-hydroxyecdysone 3-phosphate; FT = Fourier transform; HPLC = high-performance liquid chromatography; 20E = 20-hydroxyecdysone; 20Eoic = 20-hydroxyecdysonoic acid; NMR = nuclear magnetic resonance; NP-HPLC = normal phase HPLC; RP-HPLC = reverse phase HPLC; TFA = trifluoroacetic acid; Tris = tris(hydroxymethyl)-aminomethane.) analysis of metabolites. Metabolites were generally identified by comigration with available references in different HPLC systems. Analysis of compounds for which no reference was available required a large-scale preparation and purification for their identification by 1H nuclear magnetic resonance spectrometry.The metabolic reactions affect the ecdysone molecule at C-3, C-20, and C-26, leading to molecules which are modified at one, two, or three of these positions. At C-20, hydroxylation leads to 20-hydroxyecdysteroids. At C-26, hydroxylation leads to 26-hydroxyecdysteroids which can be further converted into 26-oic derivatives (ecdysonoic acids) by oxidation. At C-3, there are several possibilities: there may be oxidation into 3-dehydroecdysteroids, or epimerization possibly followed by phosphate conjugation.Thus, injected 20-hydroxyecdysone was converted principally into 20-hydroxyecdysonoic acid, 3-dehydro-20-hydroxyecdysone, and 3-epi-20-hydroxyecdysone 3-phosphate. Labelled ecdysone mainly gave the same metabolites doubled by a homologous series lacking the 20-hydroxyl group.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/arch.940040207
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