PRODUÇÃO DE PROTEASE DE ASPERGILLUS NÍGER NO CULTIVO EM ESTADO SÓLIDO EM BIOMASSA DE ARROZ E MARACUJÁ

Abstract

Investigations were carried out to describeprotease production by Aspergillus niger ATCC 16404 insolid-state fermentation (SSF). The effects of substratemoisture content (SM; 24.4, 33, 60 and 62.6%), ricebiomass concentration in passion fruit and rice mixture(RB; 0, 13, 50, 87 and 100% dry-mass), inoculum size (IS; 0.05, 0.10, 0.25, 0.40 and 0.45%) on cellular growthand protease production were examined by responsesurface methodology (RSM) and the effect of temperature(28, 35, 40 and 45oC) and culture time (0-12 days) wereevaluated under the optimal conditions. According toRSM the optimum conditions were: SM 48%, RB 35%, IS0.18%. Under the optimized conditions, the proteaseproductivity peaked after four days and the Dalsentermodel with the activation energy of protease deactivationof 144.49 kJ/mol, maximum cellular concentration of 9.98% (g/g) and specific growth rate of 0.0944h-1 providedan adequate fit of the experimental data.

Index Terms - Aspergillus niger, passion fruit biomass,protease, solid state cultivation rice.