title: Lactose hydrolysis by β-galactosidase enzyme: optimization using response surface methodology.
abstract: In the present study, it was aimed to optimize the process of lactose hydrolysis using free and immobilized β-galactosidase to produce glucose and galactose. Response surface methodology (RSM) by central composite design (CCD) was employed to optimize the degree of hydrolysis by varying three parameters, temperature (15-45°C), solution pH (5-9) and β-galactosidase enzyme concentration (2-8mg/mL) for free mode of analysis and sodium alginate concentration (2-4%), calcium chloride concentration (3-6%) and enzyme concentration (2-8mg/mL) for immobilized process. Based on plots and variance analysis, the optimum operational conditions for maximizing lactose hydrolysis were found to be temperature (35.5°C), pH (6.7) and enzyme concentration (6.7mg/mL) in free mode and sodium alginate concentration (3%), calcium chloride concentration (5.9%) and enzyme concentration (5.2mg/mL) in immobilized mode.
authors.affiliation: Chemical Engineering Department, Jadavpur University, Kolkata 700032, West Bengal, India.
authors.forename: Bipasha
authors.initials: B
authors.lastname: Das
authors.affiliation: Chemical Engineering Department, Jadavpur University, Kolkata 700032, West Bengal, India.
authors.forename: Ananda Prasad
authors.initials: AP
authors.lastname: Roy
authors.affiliation: Chemical Engineering Department, Heritage Institute of Technology, Kolkata 700107, West Bengal, India. Electronic address: sangita.bhattacharjee@heritageit.edu.
authors.forename: Sangita
authors.initials: S
authors.lastname: Bhattacharjee
authors.affiliation: Department of Chemical Engineering and Materials, University of Calabria, Cubo-44A, 87036 Rende, CS, Italy.
authors.forename: Sudip
authors.initials: S
authors.lastname: Chakraborty
authors.affiliation: Chemical Engineering Department, Jadavpur University, Kolkata 700032, West Bengal, India.
authors.forename: Chiranjib
authors.initials: C
authors.lastname: Bhattacharjee
mesh_terms: D000464:Alginates / Q000737:chemistry; D004800:Enzymes, Immobilized; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007785:Lactose / Q000737:chemistry*; D012044:Regression Analysis; D013696:Temperature; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry; D018508:Water Purification / Q000379:methods; D001616:beta-Galactosidase / Q000737:chemistry*
chemical_list: D000464:Alginates; D004800:Enzymes, Immobilized; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D007785:Lactose; D062065:Wastewater; D014874:Water Pollutants, Chemical; D001616:beta-Galactosidase
keywords: Calcium alginate; Immobilized enzyme; Lactose hydrolysis; Response surface methodology; β-galactosidase