Modeling fixed and fluidized reactors for cassava starch saccharification with immobilized enzyme

• Published in: Applied biochemistry and biotechnology Vol. 63; no. 1; pp. 527 - 540
• Main Authors: Zanin, G.M. (State University of Maringo, Maringo, PR, Brazil.), Moraes, F.F. de
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Heidelberg Springer 1997; Springer Nature B.V
• Subjects: ALMIDON; AMIDON; Biological and medical sciences; Bioreactors; Biotechnology; Cassava; Dextrin; ENZIMAS INMOVILIZADAS; ENZYME IMMOBILISEE; Enzymes; Fluidized beds; Fundamental and applied biological sciences. Psychology; HIDROLISIS; HYDROLYSE; Kinetics; MANDIOCA; MANIOC; Methods. Procedures. Technologies; Modelling; Reactors; Saccharification; Starch; Substrate inhibition; Various methods and equipments; Fluidized bed reactor; Glucan 1,4-α-glucosidase; Enzyme; Starch; Manihot esculenta; Fixed bed reactor; Saccharification; Modeling; Bioreactor; Dicotyledones; Glycosidases; Angiospermae; Euphorbiaceae; Hydrolases; Spermatophyta; Kinetics; Tuber plant; Immobilized enzyme
• ISSN: 0273-2289; 1559-0291
• DOI: 10.1007/BF02920451

Cassava starch saccharification in fixed-and fluidized-bed reactors using immobilized enzyme was modeled in a previous paper using a simple model in which all dextrins were grouped in a single substrate. In that case, although good fit of the model to experimental data was obtained, physical inconsistency appeared as negative kinetic constants. In this work, a multisubstrate model, developed earlier for saccharification with free enzyme, is adapted for immobilized enzyme. This latter model takes into account the formation of intermediate substrates, which are dextrins competing for the catalytic site of the enzyme, reversibility of some reactions, inhibition by substrate and product, and the formation of isomaltose. Kinetic parameters to be used with this model were obtained from initial velocity saccharification tests using the immobilized enzyme and different liquefied starch concentrations. The new model was found to be valid for modeling both fixed- and fluidized-bed reactors. It did not present inconsistencies as the earlier one had and has shown that apparent glucose inhibition is about seven times higher in the fixed-bed than in fluidized-bed reactor