title: A novel glucoamylase activated by manganese and calcium produced in submerged fermentation by Aspergillus phoenicis.
abstract: This study investigates the production of glucoamylase from Aspergillus phoenicis in Machado Benassi (MB) medium using 1% maltose as carbon source. The maximum amylase activity was observed after four days of cultivation, on static conditions at 30 °C. Glucoamylase production was induced by maltose and inhibited by different glucose concentrations. The optimum of temperature and pH were 60-65 °C, and 4.5 or 5.0 to sodium acetate and Mcllvaine buffers, respectively. It was observed that the enzyme was totally stable at 30-65 °C for 1 h, and the pH range was 3.0-6.0. The enzyme was mainly activated by manganese (176%), and calcium (130%) ions. The products of starch hydrolysis were analyzed by thin layer chromatography and after 3 h, only glucose was detected, characterizing the amylolytic activity as a glucoamylase.
authors.affiliation: Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Vivian Machado
authors.initials: VM
authors.lastname: Benassi
authors.forename: Thiago Machado
authors.initials: TM
authors.lastname: Pasin
authors.forename: Fernanda Dell Antonio
authors.initials: FD
authors.lastname: Facchini
authors.forename: João Atílio
authors.initials: JA
authors.lastname: Jorge
authors.forename: Maria de Lourdes
authors.initials: Mde L
authors.lastname: Teixeira de Moraes Polizeli
mesh_terms: D001230:Aspergillus / Q000201:enzymology* / Q000254:growth & development*; D002118:Calcium / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D003470:Culture Media / Q000737:chemistry; D020536:Enzyme Activators / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism; D005285:Fermentation; D005087:Glucan 1,4-alpha-Glucosidase / Q000302:isolation & purification* / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008320:Maltose / Q000378:metabolism; D008345:Manganese / Q000378:metabolism*; D019346:Sodium Acetate / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D013696:Temperature
chemical_list: D003470:Culture Media; D020536:Enzyme Activators; D004791:Enzyme Inhibitors; D008345:Manganese; D019346:Sodium Acetate; D008320:Maltose; D013213:Starch; D005087:Glucan 1,4-alpha-Glucosidase; D005947:Glucose; D002118:Calcium
keywords: Activation; Aspergillus phoenicis; Calcium activation; Glucoamylase; Manganese activation