title: Cellulase production by Aspergillus japonicus URM5620 using waste from castor bean (Ricinus communis L.) under solid-state fermentation.
abstract: The activity of β-glucosidase (βG), total cellulase (FPase) and endoglucanase (CMCase), produced by Aspergillus japonicus URM5620, was studied on solid-state fermentation using castor bean meal as substrate. The effect of the substrate amount, initial moisture, pH, and temperature on cellulase production was studied using a full factorial design (2(4)). The maximum βG, FPase, and CMCase activity was 88.3, 953.4, and 191.6 U/g dry substrate, respectively. The best enzyme activities for all three enzymes were obtained at the same conditions with 5.0 g of substrate, initial moisture 15% at 25 °C and pH 6.0 with 120 h of fermentation. The optimum activity for FPase and CMCase was found at pH 3.0 at an optimum temperature of 50 °C for FPase and of 55 °C for CMCase. The cellulases were stable in the range of pH 3.0-10.0 at 50 °C temperature. The enzyme production optimization demonstrated clearly the impact of the process parameters on the yield of the cellulolytic enzymes.
authors.affiliation: Mycology Department, Federal University of Pernambuco, Cidade Universitária, CEP 50670-420 Recife, Pernambuco, Brazil.
authors.forename: Polyanna Nunes
authors.initials: PN
authors.lastname: Herculano
authors.forename: Tatiana Souza
authors.initials: TS
authors.lastname: Porto
authors.forename: Keila Aparecida
authors.initials: KA
authors.lastname: Moreira
authors.forename: Gustavo A S
authors.initials: GA
authors.lastname: Pinto
authors.forename: Cristina Maria
authors.initials: CM
authors.lastname: Souza-Motta
authors.forename: Ana Lúcia F
authors.initials: AL
authors.lastname: Porto
mesh_terms: D000465:Algorithms; D001230:Aspergillus / Q000201:enzymology*; D002367:Ricinus communis / Q000378:metabolism*; D002480:Cellulase / Q000096:biosynthesis*; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D007218:Industrial Microbiology / Q000379:methods*; D007700:Kinetics; D013696:Temperature; D014867:Water / Q000378:metabolism; D001617:beta-Glucosidase / Q000096:biosynthesis*
chemical_list: D014867:Water; D001617:beta-Glucosidase; D002480:Cellulase