Sucrose hydrolysis by invertase using a membrane reactor: effect of membrane cut-off on enzyme performance

Sucrose hydrolysis by invertase [EC.3.2.1.26] produces inverted sugar syrup, an ingredient mainly used in the food industry. To properly catalyze hydrolysis, the enzyme should be reused after this reaction. It is advisable to maintain constant activity over a considerable period. Thus, sucrose hydrolysis was performed in a membrane bioreactor - a continuously stirred tank reactor coupled with an ultrafiltration membrane (UFM) which provides good diffusion and high activity per unit volume. Molecular weight cut-off for soluble invertase UFMs was up to 100kDa. This study focused on the role of UFM invertase cut-off as it is the main element in the process. We demonstrated that both the cut-off and chemical nature of the UFM affected specific invertase activity.

转化酶[EC.3.2.1.26]催化蔗糖水解可制备转化糖浆，该产物主要作为配料应用于食品工业。为保障水解反应顺利进行并实现酶的重复利用，需在较长运行周期内维持酶的恒定活性。为此，本研究采用膜生物反应器（membrane bioreactor）开展蔗糖水解实验：该体系由耦合超滤膜（ultrafiltration membrane，UFM）的连续搅拌釜式反应器（continuously stirred tank reactor）构成，兼具良好的传质性能与单位体积高催化活性。用于可溶性转化酶的超滤膜截留分子量上限为100 kDa。本研究重点探究了超滤膜截留分子量在该工艺中的核心作用，因其为工艺的核心元件。研究结果表明，超滤膜的截留分子量与化学性质均会对转化酶比活产生显著影响。