Matsuda Yoshikazu, Sumida Natsumi, Yoshida Munehiro
Japan Clinic Co., Uzumasa Kai-nichi 10- 1, Ukyo-ku, Kyoto 616-8555, Japan.
J Nutr Sci Vitaminol (Tokyo). 2003 Dec;49(6):405-8. doi: 10.3177/jnsv.49.405.
To obtain information on the luminal absorption of oyster zinc, the zinc action during an in vitro protease digestion of oysters was examined. More than 90% of the zinc rendered solute at pH 1.3 or 3.0 irrespective of the pepsin digestion. The solute zinc was partially re-precipitated by neutralization, and trypsin digestion did not render the re-precipitated zinc solute. When the pepsin digestion was performed at pH 5.0, the ratio of soluble zinc in trypsin digest decreased. When the trypsin digest was fractionated by Sephadex G-25 , the zinc was eluted later than the peptide fragments. These results indicate that the pH of the stomach juice rather than peptides released by the digestion of oyster protein highly contributes to the oyster zinc in the small intestine becoming solute.
为获取有关牡蛎锌腔内吸收的信息，研究了牡蛎体外蛋白酶消化过程中的锌作用。无论胃蛋白酶消化情况如何，超过90%的锌在pH 1.3或3.0时变为溶质。溶质锌通过中和部分重新沉淀，胰蛋白酶消化未使重新沉淀的锌溶质溶解。当在pH 5.0进行胃蛋白酶消化时，胰蛋白酶消化物中可溶性锌的比例降低。当用葡聚糖G-25对胰蛋白酶消化物进行分级分离时，锌的洗脱晚于肽片段。这些结果表明，胃液的pH值而非牡蛎蛋白消化释放的肽对小肠中牡蛎锌变为溶质的贡献更大。
