The influence of temperature upon the hydrolysis of cellobiose by β-1,4-glucosidases from Aspergillus niger

• Published in: Enzyme and microbial technology Vol. 26; no. 8; pp. 614 - 620
• Main Authors: Bravo, V., Paez, M.P., Aoulad, M., Reyes, A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.05.2000; Elsevier Science
• Subjects: Activation energy; Aspergillus niger; Beta-1,4-glucosidase; Bioconversions. Hemisynthesis; Biological and medical sciences; Biopolymers; Biotechnology; Cellobiose; Enzymatic hydrolysis; Enzyme inhibition; Fundamental and applied biological sciences. Psychology; Fungi; Glucose; Hydrolysis; Mathematical models; Methods. Procedures. Technologies; Numerical methods; Rate constants; Thermal effects; Beta-1,4-glucosidase; Cellobiose; Aspergillus niger; Enzymatic hydrolysis; Temperature; Enzyme; Environmental factor; Glucose; Fungi; Hydrolysis; Kinetic model; β-Glucosidase; Glycosidases; Concentration effect; Hydrolases; Fungi Imperfecti; O-Glycosidases; Thallophyta; Enzymatic reaction
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/S0141-0229(00)00136-8

We have made experimental studies into the enzymatic hydrolysis of cellobiose within the temperature range of 40°C to 70°C at pH 4.9, by using β-1,4-glucosidase from Aspergillus niger. At 70°C there was significant enzyme deactivation, which could be fitted to a potential deactivation model with values of n equal to 1.09 and k d to 0.1564 (g/l) −0.09 min −1, whereas the rate of hydrolysis could be fitted to the Michaelis–Menten equation. Between 40°C and 60°C we noted a substrate inhibition and that the CEC compound formed contributed to glucose production. The apparent activation energies had values of 4.66, 8.45, 4.82, and 3.99 kJ/mol for the kinetic constants k a and k a2 the Michaelis constant and the substrate inhibition constant, respectively.