Amyloglucosidase enzyme was produced by Aspergillus niger NRRL 3122 from solid-state fermentation, using deffated rice bran as substrate. The effects of process parameters (pH, temperature) in the equilibrium partition coefficient for the system amyloglucosidase - resin DEAE-cellulose were investigated, aiming at obtaining the optimum conditions for a subsequent purification process. The highest partition coefficients were obtained using 0.025M Tris-HCl buffer, pH 8.0 and 25ºC. The conditions that supplied the highest partition coefficient were specified, the isotherm that better described the amyloglucosidase process of adsorption obtained. It was observed that the adsorption could be well described by Langmuir equation and the values of Qm and Kd estimated at 133.0 U mL-1 and 15.4 U mL-1, respectively. From the adjustment of the kinetic curves using the fourth-order Runge-Kutta algorithm, the adsorption (k1) and desorption (k2) constants were obtained through optimization by the least square procedure, and the values calculated were 2.4x10-3 mL U-1 min-1 for k1 and 0.037 min-1 for k2 .
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机译：黑曲霉NRRL 3122使用脱脂的米糠作为底物，通过固态发酵生产淀粉葡糖苷酶。研究了工艺参数（pH，温度）对淀粉葡糖苷酶-树脂DEAE-纤维素体系的平衡分配系数的影响，旨在为后续纯化工艺获得最佳条件。使用0.025M Tris-HCl缓冲液，pH 8.0和25ºC可获得最高的分配系数。指定提供最高分配系数的条件，等温线可以更好地描述所获得的淀粉葡糖苷酶的吸附过程。观察到吸附可以通过Langmuir方程很好地描述，Qm和Kd值分别估计为133.0 U mL-1和15.4 U mL-1。通过使用四阶Runge-Kutta算法调整动力学曲线，通过最小二乘法优化获得吸附（k1）和解吸（k2）常数，计算得出的值为2.4x10-3 mL U- k1为1 min-1，k2为0.037 min-1。
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