Chiang C J, Lee W C, Sheu D C, Duan K J
Department of Chemical Engineering, National Chung Cheng University, Chiayi, Taiwan.
Biotechnol Prog. 1997 Sep-Oct;13(5):577-82. doi: 10.1021/bp970067z.
beta-Fructofuranosidases from Aspergillus niger ATCC 20611 and Aspergillus japonicus TIT-KJ1 were purified and immobilized covalently onto methacrylamide-based polymeric beads. The porous, oxriane-containing support was reactive and could bind enzymes in a buffered solution at room temperature with a density up to 0.4 mg of protein g-1 of support with 100% immobilized yield. Neither the optimum temperature for the highest enzymatic activities nor the batch reaction pattern for fructooligosaccharides formation catalyzed by beta-fructofuranosidases was changed by immobilization. The amount of fructooligosaccharides produced from 50% (w/w) sucrose solution using the prepared immobilized enzymes was determined to be approximately 60% of the total sugars in the reaction mixtures. This level of fructooligosaccharides produced by the immobilized enzymes was comparable to that resulting from processes employing other immobilized biocatalysts as shown in the literature. The fraction of total fructooligosaccharides presented in the final mixture increased with the initial sucrose concentration, while fractions of glucose and fructose decreased with an increase sucrose concentration.
对黑曲霉ATCC 20611和日本曲霉TIT-KJ1来源的β-呋喃果糖苷酶进行了纯化，并将其共价固定在基于甲基丙烯酰胺的聚合物珠上。这种含环氧乙烷的多孔载体具有反应活性，在室温下的缓冲溶液中能够结合酶，固定化产率达100%，蛋白质结合密度高达每克载体0.4毫克。固定化既未改变β-呋喃果糖苷酶催化最高酶活性的最适温度，也未改变低聚果糖形成的分批反应模式。使用制备的固定化酶从50%（w/w）蔗糖溶液中产生的低聚果糖量被确定为反应混合物中总糖的约60%。文献表明，固定化酶产生的这种低聚果糖水平与使用其他固定化生物催化剂的过程所产生的水平相当。最终混合物中总低聚果糖的比例随初始蔗糖浓度的增加而增加，而葡萄糖和果糖的比例随蔗糖浓度的增加而降低。
