Continuous sucrose hydrolysis by an immobilized whole yeast cell biocatalyst

Abstract

An immobilized biocatalyst with invertase activity prepared by immobilization of whole yeast cells without use of any insoluble carrier was tested in tubular fixed-bed reactors from the point of view of possible application for continuous full-scale sucrose hydrolysis. At inlet sucrose concentration above 60% (w/w) and reaction temperature 60–70°C, total sucrose hydrolysis was achieved at a flow rate of 0.6–1.5 bed volumes per hour. At a flow rate about 10 bed volumes per hour, the conversion was still 0.5. The specific productivity of the biocatalyst was 3–25 h −1; the productivity of the reactor was 1–9 kg l −1 h −1. The half-life of the biocatalyst invertase activity was 815 h at 70°C. The specific pressure drop over the biocatalyst bed was less than 23 kPa m −1. The biocatalyst was proved to be fully capable of continuous sucrose hydrolysis in fixed-bed reactors.