Muzhingi Tawanda, Yeum Kyung-Jin, Russell Robert M, Johnson Elizabeth J, Qin Jian, Tang Guangwen
Dorothy J. and Gerald R. Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA 02111, USA.
Int J Vitam Nutr Res. 2008 May;78(3):112-20. doi: 10.1024/0300-9831.78.3.112.
Maize is an important staple food consumed by millions of people in many countries. Yellow maize naturally contains carotenoids which not only provide provitamin A carotenoids but also xanthophylls, which are known to be important for eye health. This study was aimed at 1) evaluating the effect of saponification during extraction of yellow maize carotenoids, 2) determining the major carotenoids in 36 genotypes of yellow maize by high-performance liquid chromatography with a C30 column, and 3) determining the effect of cooking on the carotenoid content of yellow maize. The major carotenoids in yellow maize were identified as all-trans lutein, cis-isomers of lutein, all-trans zeaxanthin, alpha- and beta-cryptoxanthin, all-trans beta-carotene, 9-cis beta-carotene, and 13-cis beta-carotene. Our results indicated that carotenoid extraction without saponification showed a significantly higher yield than that obtained using saponification. Results of the current study indicate that yellow maize is a good source of provitamin A carotenoids and xanthophylls. Cooking by boiling yellow maize at 100 degrees C for 30 minutes increased the carotenoid concentration, while baking at 450 degrees F for 25 minutes decreased the carotenoid concentrations by almost 70% as compared to the uncooked yellow maize flour.
玉米是许多国家数百万人食用的重要主食。黄玉米天然含有类胡萝卜素，这些类胡萝卜素不仅能提供维生素A原类胡萝卜素，还含有叶黄素，而叶黄素对眼睛健康很重要。本研究旨在：1）评估黄玉米类胡萝卜素提取过程中皂化的效果；2）通过使用C30柱的高效液相色谱法测定36个黄玉米基因型中的主要类胡萝卜素；3）确定烹饪对黄玉米类胡萝卜素含量的影响。黄玉米中的主要类胡萝卜素被鉴定为全反式叶黄素、叶黄素的顺式异构体、全反式玉米黄质、α-和β-隐黄质、全反式β-胡萝卜素、9-顺式β-胡萝卜素和13-顺式β-胡萝卜素。我们的结果表明，不进行皂化的类胡萝卜素提取产率显著高于使用皂化法获得的产率。当前研究结果表明，黄玉米是维生素A原类胡萝卜素和叶黄素的良好来源。将黄玉米在100摄氏度下煮30分钟会增加类胡萝卜素浓度，而在450华氏度下烘烤25分钟会使类胡萝卜素浓度比未煮过的黄玉米粉降低近70%。
