Teng C D, Zarrintan M H, Groves M J
Pharmaceutics Department, College of Pharmacy, University of Illinois, Chicago 60612.
Pharm Res. 1991 Feb;8(2):191-5. doi: 10.1023/a:1015835902721.
Using a protein isolated from soy, a dynamic water adsorption method was developed and the data were compared with those obtained from a static gravimetric procedure. Both methods gave comparable results, showing that Type II isotherms with considerable hysteresis were obtained. However, the dynamic procedure was preferred since it provided data rapidly and used significantly less material. Using the dynamic method, water adsorption isotherms at 25 degrees C were also determined for four biologically active proteins: alpha-amylase, beta-glucuronidase, lipase, and urease. BET (Brunauer, Emmet, and Teller) parameters were calculated and the specific surface areas for the native, biologically active proteins were found to be similar, 238.4 +/- 20.2 m2/g. On the other hand, the specific surface area for the denatured soy protein isolate was 144.6 m2/g. Nevertheless, the heat of absorbance for all of the proteins examined was similar, suggesting that they have comparable degrees of hydrophilicity.
使用从大豆中分离出的一种蛋白质，开发了一种动态水吸附方法，并将数据与通过静态重量法获得的数据进行比较。两种方法得到了可比的结果，表明获得了具有相当滞后现象的II型等温线。然而，动态方法更受青睐，因为它能快速提供数据且使用的材料显著更少。使用动态方法，还测定了四种生物活性蛋白质在25摄氏度下的水吸附等温线：α-淀粉酶、β-葡萄糖醛酸酶、脂肪酶和脲酶。计算了BET（布鲁瑙尔、埃米特和特勒）参数，发现天然生物活性蛋白质的比表面积相似，为238.4±20.2平方米/克。另一方面，变性大豆分离蛋白的比表面积为144.6平方米/克。尽管如此，所有检测蛋白质的吸附热相似，表明它们具有相当的亲水性程度。
