title: [Identification of beta, beta-caroten-2-ol and beta, beta-carotene-2,2'-diol in the stick insect, Carausius morosus Br.; a reinvestigation study].
abstract: Two major carotenoids of the stick insect were reinvestigated and shown to be beta,beta-caroten-2-ol and beta,beta-carotene-2,2'-diol and not isocryptoxanthin (beta,beta-carotin-4-ol) and isozeaxaanthin (beta,beta-carotene-4,4'-diol). Both pigments are esterified with fatty acids. The identification is based on cochromatography with authentic 2-, 3- and 4-isomers of the mono- and dihydroxy pigment, mass spectra, and chemical behaviour. In acid solution beta-beta-carotene-2,2'-diol is specifically dehydrogenated and rearranged to ketones with retro structures in analogy to the reactionof beta,beta-caroten-2-ol as recently reported. The final product of the diol is 4,5-dihydro-4,5'-retro-beta,beta-carotene-2,2'-dione. This is the first demonstration of beta,beta-carotene-2,2'-diol in an animal.
mesh_terms: D000818:Animals; D002338:Carotenoids / Q000032:analysis*; D002855:Chromatography, Thin Layer; D013058:Mass Spectrometry; D009987:Orthoptera / Q000032:analysis*; D013053:Spectrophotometry
chemical_list: D002338:Carotenoids