title: Production, partial characterization, and immobilization in alginate beads of an alkaline protease from a new thermophilic fungus Myceliophthora sp.
abstract: Thermophilic fungi produce thermostable enzymes which have a number of applications, mainly in biotechnological processes. In this work, we describe the characterization of a protease produced in solidstate (SSF) and submerged (SmF) fermentations by a newly isolated thermophilic fungus identified as a putative new species in the genus Myceliophthora. Enzyme-production rate was evaluated for both fermentation processes, and in SSF, using a medium composed of a mixture of wheat bran and casein, the proteolytic output was 4.5-fold larger than that obtained in SmF. Additionally, the peak of proteolytic activity was obtained after 3 days for SSF whereas for SmF it was after 4 days. The crude enzyme obtained by both SSF and SmF displayed similar optimum temperature at 50 degrees C, but the optimum pH shifted from 7 (SmF) to 9(SSF). The alkaline protease produced through solid-state fermentation (SSF), was immobilized on beads of calcium alginate, allowing comparative analyses of free and immobilized proteases to be carried out. It was observed that both optimum temperature and thermal stability of the immobilized enzyme were higher than for the free enzyme. Moreover, the immobilized enzyme showed considerable stability for up to 7 reuses.
authors.affiliation: UNESP - Univ Estadual Paulista IBILCE, São José do Rio Preto SP, 15054-000, Brazil.
authors.forename: Letícia Maria
authors.initials: LM
authors.lastname: Zanphorlin
authors.forename: Fernanda Dell Antonio
authors.initials: FD
authors.lastname: Facchini
authors.forename: Filipe
authors.initials: F
authors.lastname: Vasconcelos
authors.forename: Rafaella Costa
authors.initials: RC
authors.lastname: Bonugli-Santos
authors.forename: André
authors.initials: A
authors.lastname: Rodrigues
authors.forename: Lara Durães
authors.initials: LD
authors.lastname: Sette
authors.forename: Eleni
authors.initials: E
authors.lastname: Gomes
authors.forename: Gustavo Orlando
authors.initials: GO
authors.lastname: Bonilla-Rodriguez
mesh_terms: D000464:Alginates; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism*; D010450:Endopeptidases / Q000302:isolation & purification / Q000378:metabolism*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism; D005285:Fermentation; D005656:Fungal Proteins / Q000302:isolation & purification / Q000378:metabolism*; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010802:Phylogeny; D020037:Sordariales / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D013696:Temperature
chemical_list: D000464:Alginates; D001426:Bacterial Proteins; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D010450:Endopeptidases; C087822:alkaline protease