Packed-bed reactor performance with immobilized lactase under thermal inactivation

• Published in: Enzyme and microbial technology Vol. 23; no. 1; pp. 3 - 9
• Main Authors: Illanes, A., Altamirano, C., Aillapán, A., Tomasello, G., Zuñiga, M.E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.07.1998; Elsevier Science
• Subjects: Biological and medical sciences; Bioreactors; Biotechnology; Enzyme inactivation; enzyme reactor performance; Fundamental and applied biological sciences. Psychology; immobilized lactase; Kluyveromyces marxianus marxianus; Methods. Procedures. Technologies; modulation of thermal inactivation; Various methods and equipments; immobilized lactase; Enzyme inactivation; modulation of thermal inactivation; enzyme reactor performance; Packed bed; Temperature; Enzyme; Inactivation; Bioreactor; Experimental result; Glycosidases; Modulation; Hydrolases; Kinetics; Mathematical model; O-Glycosidases; Immobilized enzyme; β-Galactosidase
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/S0141-0229(98)00027-1

Thermal inactivation of immobilized lactase has been studied in the presence of substrate and products. Modulation factors of thermal inactivation have been determined for lactose and galactose based on a two-stage series-type mechanism of inactivation. Galactose was a positive modulator of enzyme stability while the opposite occurred with lactose; the glucose effect was negligible. A model for packed-bed continuous reactor operation with chitin-immobilized lactase from Kluyveromyces marxianus var. marxianus was developed considering modulated thermal inactivation and appropriate kinetic expression for lactose hydrolysis. Experimental results were in good agreement with the model which was a far better representation of reactor performance than the conventional model not considering the effect of substrate and products on enzyme inactivation.