Liu Chang-Shu, Glahn Raymond P, Liu Rui Hai
Department of Food Science and Institute of Comparative and Environmental Toxicology, Stocking Hall, Cornell University, Ithaca, New York 14853, USA.
J Agric Food Chem. 2004 Jun 30;52(13):4330-7. doi: 10.1021/jf040028k.
Epidemiological studies have shown that consumption of carotenoid-rich fruits and vegetables is associated with a reduced risk of developing chronic diseases. beta-Carotene, alpha-carotene, and beta-cryptoxanthin are precursors of vitamin A, a nutrient essential for human health. However, little is known about the bioavailability of carotenoids from whole foods. This study characterized the intestinal uptake performance of carotenoids using monolayers of differentiated Caco-2 human intestinal cells and mimicked human digestion to assess carotenoid absorption from carrots and corn. Results showed that Caco-2 cellular uptake of beta-carotene and zeaxanthin was higher than that of lutein. Uptake performances of pure carotenoids and carotenoids from whole foods by Caco-2 cells were both curvilinear, reaching saturated levels after 4 h of incubation. The time kinetics and dose response of carotenoid uptake presented a similar pattern in Caco-2 cells after plating for 2 and 14 days. Furthermore, the applicability of this new model was verified with whole grain corn, showing that cooked corn grain significantly enhanced carotenoid bioavailability. These results support the feasibility of the in vitro digestion cell model for assessing carotenoid absorption from whole foods as a suitable and cost-effective physiological alternative to current methodologies.
流行病学研究表明，食用富含类胡萝卜素的水果和蔬菜与降低患慢性病的风险有关。β-胡萝卜素、α-胡萝卜素和β-隐黄质是维生素A的前体，维生素A是人体健康必需的营养素。然而，对于全食物中类胡萝卜素的生物利用度知之甚少。本研究利用分化的Caco-2人肠道细胞单层来表征类胡萝卜素的肠道摄取性能，并模拟人体消化过程以评估胡萝卜和玉米中类胡萝卜素的吸收情况。结果表明，Caco-2细胞对β-胡萝卜素和玉米黄质的摄取高于叶黄素。Caco-2细胞对纯类胡萝卜素和全食物中类胡萝卜素的摄取性能均呈曲线关系，孵育4小时后达到饱和水平。接种2天和14天后，Caco-2细胞中类胡萝卜素摄取的时间动力学和剂量反应呈现相似模式。此外，用全谷物玉米验证了该新模型的适用性，结果表明煮熟的玉米粒显著提高了类胡萝卜素的生物利用度。这些结果支持了体外消化细胞模型作为评估全食物中类胡萝卜素吸收的可行性，它是一种适合且经济高效的生理学替代方法，可替代当前的方法。
