title: [Influence of amaranth on the production of alpha-amylase using Aspergillus niger NRRL 3112].
abstract: In this paper the influence of the amaranth seed meal and the aeration conditions on the alpha-amylase production by Aspergillus niger NRRL 3112 were studied. The assays of selection of culture medium were carried out in a rotary shaker at 250 rpm and 2.5 cm stroke. The aeration conditions were studied in a mechanically stirred fermentor New Brunswick type. A concentration of alpha-amylase of 2750 U.Dun/ml was achieved at 120 h with a dry weight of 8.0 g/l, using a base medium with 5.0 g/l Amaranthus cruentus seed meal. In the experiment performed in a New Brunswick fermentor, the highest value was 2806 U.Dun/ml. This result was obtained after 120 h, operating at 300 rpm and an airflow of 1 l/l. min. in a limited dissolved oxygen concentration. It was determined that the increase in the agitation rate was not favorable to the enzyme production, despite that an increase was verified in the dissolved oxygen. The morphology of the microorganism, in long and ramified hyphae, was the critical factor to obtain higher levels of alpha-amylase.
authors.affiliation: Departamento de Química, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina. bioquim@ssdnet.com.ar
authors.forename: D D
authors.initials: DD
authors.lastname: Mariani
authors.forename: G
authors.initials: G
authors.lastname: Lorda
authors.forename: A P
authors.initials: AP
authors.lastname: Balatti
mesh_terms: D000548:Amaranth Dye / Q000494:pharmacology*; D001234:Aspergillus niger / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development; D004396:Coloring Agents / Q000494:pharmacology*; D003470:Culture Media / Q000737:chemistry*; D005285:Fermentation; D005656:Fungal Proteins / Q000096:biosynthesis*; D007202:Indicators and Reagents / Q000494:pharmacology*; D000516:alpha-Amylases / Q000096:biosynthesis*
chemical_list: D004396:Coloring Agents; D003470:Culture Media; D005656:Fungal Proteins; D007202:Indicators and Reagents; D000548:Amaranth Dye; D000516:alpha-Amylases