02684naa a2200349 a 450000100080000000500110000800800410001902200140006002400390007410000190011324501360013226000090026852016820027765000150195965000120197465000130198665000110199965000180201065300140202865300150204265300150205765300140207265300180208665300120210465300360211665300290215270000210218170000190220270000220222170000140224377300770225719019852019-01-29       2011    bl uuuu     u00u1 u    #d  a0926-66907 a10.1016/j.indcrop.2011.04.0062DOI1 aFARINAS, C. S.  aModeling the effects of solid state fermentation operating conditions on endoglucanase production using an instrumented bioreactor.  c2011  aCellulase production is one of the most critical steps in the economics of second generation ethanol. Although solid-state fermentation (SSF) is an attractive process for the production of enzymes, SSF is highly limited by the difficulty in controlling the operating variables which affect microbial growth and metabolites production. In this context, this work evaluates the effects of operational conditions on endoglucanase production by a selected strain of Aspergillus niger cultivated under SSF using an instrumented lab-scale bioreactor equipped with an on-line automated monitoring and control system. The effects of air flow rate, inlet air relative humidity and substrate initial moisture on endoglucanase production were evaluated using a statistical design methodology. A correlation coefficient of 0.9106 and a calculated value of F, 5.46 folds higher than the listed value (P-value &lt 0.05) allowed the modeling of endoglucanase production under different process conditions. Higher endoglucanase production (56.1 U/g) was achieved for a selected condition of substrate initial moisture of 72%, air inlet humidity of 70%, and flow rate of 20 mL/min. A significant increase in endoglucanase production was also found to be achieved under forced aeration conditions (50.2 IU/g) compared to static conditions (29.8 IU/g) after 72 h of cultivation. Besides, respirometric analysis revealed that the total amount of CO2 produced was linearly correlated with enzyme production (R2 of 0.988). The bioreactor system used, as well as the methodology employed herein, was very effective in evaluating the influence of operational variables on enzymes production under SSF.  aBioethanol  aEnzymes  aCelulase  aEnzima  aFermentação  aBioetanol  aBioreactor  aBiorreator  aCellulase  aEndoglucanase  aEnzimas  aFermentação em estado sólido  aSolid-state fermentation1 aVITCOSQUE, G. L.1 aFONSECA, R. F.1 aBERTUCCI NETO, V.1 aCOURI, S.  tIndustrial crops and products, [S. l.]gv. 34, n. 1, p. 1186-1192, 2011.