García-de Blas Esther, Mateo Rafael, Guzmán Bernardo Francisco Javier, Rodríguez Martín-Doimeadios Rosa Carmen, Alonso-Alvarez Carlos
Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC, UCLM, JCCM), Ronda de Toledo s/n, 13071, Ciudad Real, Spain,
Naturwissenschaften. 2014 May;101(5):407-16. doi: 10.1007/s00114-014-1169-z. Epub 2014 Apr 2.
Carotenoids are organic pigments involved in several important physiological functions and may serve as indicators of individual quality in animals. These pigments are only obtained by animals from the diet, but they can be later transformed into other carotenoids by specific enzymatic reactions. The diet of farm-reared and probably wild red-legged partridges (Alectoris rufa) is mainly based on cereals that contain high levels of lutein and zeaxanthin. These two carotenoids are also predominant in internal tissues and blood of red-legged partridges. However, in their integuments, astaxanthin and papilioerythrinone (the last one identified in this work) are mainly present in their free form and esterified with fatty acids. According to available literature about carotenoid metabolism in animals, we propose that astaxanthin (λ max = 478 nm) and papilioerythrinone (λ max = 452-478 nm) are the result of a chromatic convergence of the transformation of dietary zeaxanthin and lutein, respectively. Moreover, the results obtained in this work provide the first identification by liquid chromatography coupled to accurate mass quadrupole time-of-flight mass spectrometer system of papilioerythrinone (m/z 581.3989 M + H) in the skin (i.e., not feathers) of a vertebrate. Astaxanthin and papilioerythrinone are very close in terms of chemical structure and coloration, and the combination of these two keto-carotenoids is responsible for the red color of the ornaments in red-legged partridges.
类胡萝卜素是参与多种重要生理功能的有机色素，可能作为动物个体质量的指标。这些色素只能由动物从饮食中获取，但随后可通过特定的酶促反应转化为其他类胡萝卜素。养殖的以及可能野生的红腿鹧鸪（Alectoris rufa）的饮食主要以含有高水平叶黄素和玉米黄质的谷物为基础。这两种类胡萝卜素在红腿鹧鸪的内部组织和血液中也占主导地位。然而，在它们的体表，虾青素和蝴蝶红素（本文首次鉴定出的一种）主要以游离形式存在，并与脂肪酸酯化。根据有关动物类胡萝卜素代谢的现有文献，我们提出虾青素（λ max = 478 nm）和蝴蝶红素（λ max = 452 - 478 nm）分别是饮食中玉米黄质和叶黄素转化的颜色趋同的结果。此外，本研究获得的结果首次通过液相色谱与精确质量四极杆飞行时间质谱仪系统在脊椎动物的皮肤（即非羽毛）中鉴定出蝴蝶红素（m/z 581.3989 M + H）。虾青素和蝴蝶红素在化学结构和颜色方面非常接近，这两种酮类类胡萝卜素的组合导致了红腿鹧鸪体表装饰的红色。
