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Hydrolysis of raffinose in a hollow-fiber reactor using an unrefined mixture of alpha-galactosidase and invertase

Silman, R.W., Black, L.T., McGhee, J.E., Bagley, E.B.
Biotechnology and bioengineering 1980 v.22 no.3 pp. 533
beta-fructofuranosidase, alpha-galactosidase, Aspergillus awamori, enzyme activity, enzymatic hydrolysis, raffinose, bioreactors, melibiose, sucrose, galactose, glucose, fructose
Raffinose was converted enzymatically in a hollow-fiber reactor to melibiose, sucrose, galactose, glucose and fructose. The enzymes were a crude extract of .alpha.-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 2 levels 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 ln (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 1st-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 ln (C/C0) vs. Q-1 plots is excellent and should prove useful in reactor design considerations.