Kayser H
Z Naturforsch C Biosci. 1976 Nov-Dec;31(11-12):645-51.
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.
对竹节虫的两种主要类胡萝卜素进行了重新研究，结果表明它们是β,β-胡萝卜素-2-醇和β,β-胡萝卜素-2,2'-二醇，而非异隐黄质（β,β-胡萝卜素-4-醇）和异玉米黄质（β,β-胡萝卜素-4,4'-二醇）。这两种色素都与脂肪酸发生了酯化反应。该鉴定基于与单羟基和二羟基色素的真实2-、3-和4-异构体的共色谱分析、质谱以及化学行为。在酸性溶液中，β,β-胡萝卜素-2,2'-二醇会像最近报道的β,β-胡萝卜素-2-醇的反应那样，特异性地脱氢并重排为具有反式结构的酮。二醇的最终产物是4,5-二氢-4,5'-反式-β,β-胡萝卜素-2,2'-二酮。这是首次在动物体内证实β,β-胡萝卜素-2,2'-二醇的存在。
