Department of Human Nutrition/Centre for Advanced Food Studies, Faculty of Life Sciences, University of Copenhagen, Rolighedsvej 30, Frederiksberg C, Denmark.
J Trace Elem Med Biol. 2010 Oct;24(4):230-5. doi: 10.1016/j.jtemb.2010.06.002. Epub 2010 Sep 15.
The present in vitro studies report on iron uptake by Caco-2 cells from pepsin and pepsin+pancreatin-digested pork meat proteins at pH values between 4.6 and 7 mimicking conditions in the duodenum and the proximal jejunum, respectively. Heat treatment of the pork meat resulted in increased iron uptake from pepsin-digested samples to Caco-2 cells at pH 4.6. The major enhancing effects on iron uptake by Caco-2 cells were observed after pepsin digestion in the pH range 4.6-6.0, whereas the pepsin+pancreatin-digested samples resulted in negligible iron uptake in Caco-2 cells at pH 7. Thus, the results emphasize the importance of separating pepsin-digested and pepsin+pancreatin-digested proteins during in vitro studies on iron availability. Furthermore, the present results showed the pH dependency of iron uptake anticipated. The enhancing effect of ascorbic acid was verified by increased iron uptake from pepsin-digested pork meat samples at pH 4.6, while no effect of ascorbic acid was observed at pH 7 in pepsin+pancreatin-digested samples.
本体外研究报告了在 pH 值分别为 4.6 和 7 时，胃蛋白酶和胃蛋白酶+胰酶消化的猪肉蛋白中 Caco-2 细胞对铁的摄取情况，以模拟十二指肠和空肠近端的条件。猪肉的热处理导致在 pH 值为 4.6 时，从胃蛋白酶消化样品中摄取的铁增加。在 pH 值为 4.6-6.0 的范围内，胃蛋白酶消化后观察到对 Caco-2 细胞中铁摄取的主要促进作用，而在 pH 值为 7 时，胃蛋白酶+胰酶消化的样品在 Caco-2 细胞中几乎没有铁摄取。因此，这些结果强调了在体外铁可用性研究中分离胃蛋白酶消化和胃蛋白酶+胰酶消化蛋白的重要性。此外，本研究结果显示了铁摄取的 pH 值依赖性。在 pH 值为 4.6 时，抗坏血酸增加了胃蛋白酶消化的猪肉样品中铁的摄取，验证了抗坏血酸的增强作用，而在 pH 值为 7 时，胃蛋白酶+胰酶消化的样品中没有观察到抗坏血酸的作用。
