title: Purification and characterization of glucoamylase produced by Aspergillus niger in solid state fermentation.
abstract: Glucoamylases produced by Aspergillus niger grown on wheat brain in solid cultures were purified. Four different forms, GA I, GA I', GA II and GA III, were found having apparent molecular weights of 112,000, 104,000, and 74,000 and 61,000 Da respectively. The enzymes are glycoproteins with a carbohydrate content of 16%, and optimal activity at 60 degrees C and pH 4.4. Activity was strongly inhibited by Hg2+ while Mn2+ and Fe2+ were stimulatory. The Km values for the degradation of starch and maltose were 3.5 and 7.8 mg ml-1, respectively.
authors.affiliation: Biotechnology Unit, Regional Research Laboratory, Council of Scientific and Industrial Research, Trivandrum, India.
authors.forename: P
authors.initials: P
authors.lastname: Selvakumar
authors.forename: L
authors.initials: L
authors.lastname: Ashakumary
authors.forename: A
authors.initials: A
authors.lastname: Helen
authors.forename: A
authors.initials: A
authors.lastname: Pandey
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D002241:Carbohydrates / Q000032:analysis; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation; D005087:Glucan 1,4-alpha-Glucosidase / Q000187:drug effects / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000494:pharmacology; D008320:Maltose / Q000378:metabolism; D008345:Manganese / Q000494:pharmacology; D008628:Mercury / Q000494:pharmacology; D013213:Starch / Q000378:metabolism; D013696:Temperature; D014908:Triticum / Q000378:metabolism
chemical_list: D002241:Carbohydrates; D008345:Manganese; D008320:Maltose; D013213:Starch; D007501:Iron; D005087:Glucan 1,4-alpha-Glucosidase; D008628:Mercury