Development of heterogeneous preparation with inulinase for tubular reactor systems

Abstract

We developed highly stable heterogeneous preparations of inulinase immobilized on the ion-exchange matrixes and show that such preparations effectively split the chemically pure inulin and the inulin contained in plant extracts.The optimal conditions of hydrolysis are created for the migration of inulin solution from top to bottom (the downsteam flow) through the column filled by immobilized compounds extracted from Kluyveromyces marxianus and Helianthus tuberosus with the flow rate of 3mL/min. For the bottom-up migration of the inulin solution (i.e. the upstream flow) through the column the flow rate of 5mL/min was found to be the most optimal for the hydrolysis.When the extract of H. tuberosus was allowed to pass through the column filled by the immobilized plant inulinase from top to bottom with the flow rate of 5–10mL/min, the conditions for hydrolysis appear to be the most optimal. The conditions for hydrolysis were also found to be favourable for the bottom-up moving of the H. tuberosus extract through the column for the flow rate of 3–5mL/min.For the yeasts inulinase immobilized on VION KN-1 the most optimal flow rates of the H. tuberosus extract in the reactor were found to be similar for the following rates of inulin flow, viz. 3mL/min for the downstream flow and 5mL/min for the upstream flow.A theoretical description of the process of the inulin hydrolysis has been proposed and experimentally verified, which allows predicting the time of the full hydrolysis at different operating conditions with an error not exceeding 20%. It could be applied for the design of continuous reactors.