Hydrolysis of raffinose in a hollow‐fiber reactor using an unrefined mixture of α‐galactosidase and invertase

Raffinose was converted enzymatically in a hollow‐fiber reactor to melibiose, sucrose, galactose, glucose and fructose. The enzymes were a crude extract of α‐galactosidase and invertase produced by Aspergillus awamori NRRL 4869 on a solid substrate, Wheat bran. With a concentration of raffinose, C0, entering the reactor at a flow rate Q, and with C being the concentration of raffinose exiting the reactor, the conversion (C/C0), was studied as a function of Q at two level of C0. The data could be fairly well fitted using the analysis of Waterland et al. even though a mixed crude enzyme system was being investigated. It was found empirically that In (C/C0) was linear in Q−1, with the absolute value of the slope decreasing with increasing C0. The linearity of such plots were predicted by Lewis and Middleman from Waterland et al. for a single enzyme system obeying first‐order kinetics, the slope being independent of C0. Although the assumptions involved in this approximate analytical solution are not valid, the observed linearity of the In (C/C0) vs. Q−1 plots is excellent and should prove useful in reactor design considerations.