Breithaupt Dietmar E, Bamedi Ameneh
Institut für Lebensmittelchemie, Universität Hohenheim, Garbenstrasse 28, D-70593 Stuttgart, Germany.
J Agric Food Chem. 2002 Nov 20;50(24):7175-81. doi: 10.1021/jf0257953.
The carotenoid pattern of four yellow- and four white-fleshed potato cultivars (Solanum tuberosum L.), common on the German market, was investigated using HPLC and LC(APCI)-MS for identification and quantification of carotenoids. In each case, the carotenoid pattern was dominated by violaxanthin, antheraxanthin, lutein, and zeaxanthin, which were present in different ratios, whereas neoxanthin, beta-cryptoxanthin, and beta,beta-carotene generally are only minor constituents. In contrast to literature data, antheraxanthin was found to be the only carotenoid epoxide present in native extracts. The total concentration of the four main carotenoids reached 175 microg/100 g, whereas the sum of carotenoid esters accounted for 41-131 microg/100 g. Therefore, carotenoid esters are regarded as quantitatively significant compounds in potatoes. For LC(APCI)-MS analyses of carotenoid esters, a two-stage cleanup procedure was developed, involving column chromatography on silica gel and enzymatic cleavage of residual triacylglycerides by lipases. This facilitated the direct identification of several potato carotenoid esters without previous isolation of the compounds. Although the unequivocal identification of all parent carotenoids was not possible, the cleanup procedure proved to be highly efficient for LC(APCI)-MS analyses of very low amounts of carotenoid esters.
利用高效液相色谱法（HPLC）和液相色谱-大气压化学电离质谱联用技术（LC(APCI)-MS）对德国市场上常见的4个黄肉和4个白肉马铃薯品种（Solanum tuberosum L.）的类胡萝卜素模式进行了研究，以鉴定和定量类胡萝卜素。在每种情况下，类胡萝卜素模式均以紫黄质、花药黄质、叶黄素和玉米黄质为主，它们以不同比例存在，而新黄质、β-隐黄质和β,β-胡萝卜素通常仅为次要成分。与文献数据不同，花药黄质被发现是天然提取物中唯一存在的类胡萝卜素环氧化物。四种主要类胡萝卜素的总浓度达到175微克/100克，而类胡萝卜素酯的总量为41 - 131微克/100克。因此，类胡萝卜素酯被认为是马铃薯中在数量上具有重要意义的化合物。对于类胡萝卜素酯的LC(APCI)-MS分析，开发了一种两步净化程序，包括硅胶柱色谱法和通过脂肪酶对残留甘油三酯进行酶促裂解。这有助于直接鉴定几种马铃薯类胡萝卜素酯，而无需事先分离这些化合物。尽管无法明确鉴定所有母体类胡萝卜素，但该净化程序被证明对于极低含量类胡萝卜素酯的LC(APCI)-MS分析非常有效。
