Nelis H J, Lavens P, Van Steenberge M M, Sorgeloos P, Criel G R, De Leenheer A P
Department of Medical Biochemistry, State University of Ghent, Belgium.
J Lipid Res. 1988 Apr;29(4):491-9.
In order to study the biological fate of all-trans- and cis-canthaxanthin in the brine shrimp Artemia, a quantitative method was developed for the determination of both carotenoids and their metabolic precursors in encysted embryos (cysts), nauplii, whole animals, organs, and subcellular fractions. This method is based on nonaqueous reversed-phase chromatography, two new exhaustive extraction procedures, and the determination of proteins in the extracted residue. Hydration of Artemia cysts caused a reversible conversion of part of the all-trans- to cis-canthaxanthin. During further pre-emergence embryonic development, there was little change in the levels of both isomers. After hatching of cysts, cis-canthaxanthin was progressively isomerized to the all-trans form, while the total (all-trans + cis) canthaxanthin to protein ratio tended to remain constant. Cis-canthaxanthin rapidly became undetectable in animals fed on algae and reappeared in females at an advanced stage of the reproductive cycle. All-trans-canthaxanthin remained present during the whole Artemia life cycle in addition to its metabolic precursors echinenone and beta-carotene. The carotenoid distribution in organs and subcellular fractions indicated high affinity of cis-canthaxanthin for the female reproductive system, oocytes in general, and yolk in particular. A role for cis-canthaxanthin is suggested at an early developmental stage, i.e., in cysts, before hatching.
为了研究全反式和顺式角黄素在卤虫中的生物学命运，开发了一种定量方法，用于测定包囊胚胎（卵囊）、无节幼体、整个动物、器官和亚细胞组分中的类胡萝卜素及其代谢前体。该方法基于非水反相色谱、两种新的彻底提取程序以及对提取残渣中蛋白质的测定。卤虫卵囊的水化导致部分全反式角黄素可逆地转化为顺式角黄素。在进一步的孵化前胚胎发育过程中，两种异构体的水平变化不大。卵囊孵化后，顺式角黄素逐渐异构化为全反式形式，而总（全反式+顺式）角黄素与蛋白质的比例趋于保持恒定。在以藻类为食的动物中，顺式角黄素很快变得无法检测到，并在生殖周期后期的雌性中重新出现。除了其代谢前体海胆酮和β-胡萝卜素外，全反式角黄素在卤虫的整个生命周期中都存在。器官和亚细胞组分中的类胡萝卜素分布表明，顺式角黄素对雌性生殖系统、一般的卵母细胞，特别是卵黄具有高度亲和力。有人提出顺式角黄素在发育早期，即在卵囊孵化前就发挥作用。
