Stintzing Florian C, Schieber Andreas, Carle Reinhold
Institute of Food Technology, Section Plant Foodstuff Technology, Hohenheim University, Garbenstrasse 25, D-70599 Stuttgart, Germany.
J Agric Food Chem. 2002 Apr 10;50(8):2302-7. doi: 10.1021/jf011305f.
Betaxanthins, the yellow-orange water-soluble pigments from yellow beet (Beta vulgaris ssp. vulgaris cv. Bejo Zaden) and cactus pear (Opuntia ficus-indica cv. Gialla) have been investigated using an HPLC system compatible with mass spectrometry. Five novel betaxanthins were found and characterized as the immonium adducts of betalamic acid with serine, gamma-aminobutyric acid, valine, isoleucine, and phenylalanine. To enable concentration of betalain samples, desalting was performed by solid-phase extraction. With this technique, betacyanins could be separated from the betaxanthins using the pH-dependent retention characteristics of red and yellow betalains. The betaxanthin fraction was taken for the preparation of betalamic acid as a precursor for semisynthetic standards. The HPLC method was applied to yellow beet and cactus pear, revealing a more complex betalain profile than described earlier, thus proving its suitability for screening of betaxanthin-containing plants as potential sources for natural food colors.
采用与质谱联用的高效液相色谱系统，对来自黄甜菜（普通甜菜亚种普通甜菜品种Bejo Zaden）和仙人掌果（印度仙人掌品种Gialla）的橙黄色水溶性色素甜菜黄素进行了研究。发现了5种新的甜菜黄素，并将其鉴定为甜菜醛氨酸与丝氨酸、γ-氨基丁酸、缬氨酸、异亮氨酸和苯丙氨酸的亚胺鎓加合物。为了浓缩甜菜红素样品，通过固相萃取进行脱盐。利用这种技术，可根据红色和黄色甜菜红素的pH依赖性保留特性，将甜菜青素与甜菜黄素分离。取甜菜黄素部分用于制备甜菜醛氨酸，作为半合成标准品的前体。该高效液相色谱法应用于黄甜菜和仙人掌果，结果表明其甜菜红素谱比之前描述的更为复杂，从而证明了该方法适用于筛选含甜菜黄素的植物作为天然食用色素的潜在来源。
