超滤技术在碱性果胶酶浓缩工艺中的应用

运用从自然界中分离得到的一株具有产生特效高活性碱性果胶酶的软腐欧文氏菌株Erwinia Carotovora IFO 3830,通过发酵得到了含有高活性碱性果胶酶的发酵液由于果胶酶在该发酵液中浓度极低,仅为数μg/g左右.为了从大量的但含有目的酶浓度却极低的溶液中将目的酶分离出来,一般所使用的化工浓缩方法由于其操作温度较高使酶产品失活而无法运用.目前被普遍用于酶浓缩的硫酸铵沉淀法,不仅化学药品的消耗极大,而且后处理工艺又比较复杂;回收得到的沉淀酶制品中因混入了大量的培养基和其他杂质,导致后处理工序的更加复杂.本研究采用截留分子量为5 000和10 000(道尔顿)的超滤平面膜组件,可以直接从去除了菌体的发酵液中浓缩回收了目的产物碱性果胶酶,在浓缩率在20倍的条件下,取得了98.3%的高回收率.此外,还对超滤过程的表观阻力、浓缩率、渗透流束和浓缩液浓度等随着起滤过程的进行的变化规律进行了较为详细的研究

Concentration of alkaline pectic lyase with ultrafiltration process

In this work, pectic lyase was concentrated from fermentation broth with ultrafiltration process at room temperature directly. The effects of pressure and operation period on recovery of target enzyme and ultrafiltration flux were studied. The suitable conditions were that the inlet pressure is 0.27～0.34 Mpa, operation period 1 hour and temperature 298.15 K. The recovery ratio of above 95 % of PATE was achieved.