title: Production and characterization of alpha-amylase from Aspergillus niger JGI 24 isolated in Bangalore.
abstract: Five fungal isolates were screened for the production of alpha-amylase using both solid-state and submerged fermentations. The best amylase producer among them, Aspergillus niger JGI 24, was selected for enzyme production by solid-state fermentation (SSF) on wheat bran. Different carbon and nitrogen supplements were used to enhance enzyme production and maximum amount of enzyme was obtained when SSF was carried out with soluble starch and beef extract (1% each) as supplements. Further attempts to enhance enzyme production by UV induced mutagenesis were carried out. Survival rate decreased with increase in duration of UV exposure. Partial purification of the enzyme using ammonium sulphate fractionation resulted in 1.49 fold increase in the enzyme activity. The enzyme showed a molecular weight of 43 kDa by SDS-PAGE. Metal ions Ca2+ and Co2+ increased the enzyme activity. The enzyme was optimally active at 30 degrees C and pH 9.5.
authors.affiliation: Department of Biotechnology, Centre for Post-Graduate Studies, Shri Bhagawan Mahaveer Jain College, Jayanagar, Bangalore. varalakshmikn@yahoo.co.in
authors.forename: K N
authors.initials: KN
authors.lastname: Varalakshmi
authors.forename: B S
authors.initials: BS
authors.lastname: Kumudini
authors.forename: B N
authors.initials: BN
authors.lastname: Nandini
authors.forename: J
authors.initials: J
authors.lastname: Solomon
authors.forename: R
authors.initials: R
authors.lastname: Suhas
authors.forename: B
authors.initials: B
authors.lastname: Mahesh
authors.forename: A P
authors.initials: AP
authors.lastname: Kavitha
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology* / Q000254:growth & development / Q000528:radiation effects; D002127:Calcium Isotopes / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D003036:Cobalt Isotopes / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007194:India; D007218:Industrial Microbiology; D009154:Mutation / Q000528:radiation effects; D009584:Nitrogen / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D013696:Temperature; D014466:Ultraviolet Rays; D000516:alpha-Amylases / Q000096:biosynthesis* / Q000302:isolation & purification / Q000528:radiation effects
chemical_list: D002127:Calcium Isotopes; D003036:Cobalt Isotopes; D002244:Carbon; D013213:Starch; D000516:alpha-Amylases; D009584:Nitrogen