Synergistic effects of agroindustrial wastes on simultaneous production of protease and α-amylase under solid state fermentation using a simplex centroid mixture design

Wheat bran, soybean meal and cottonseed meal, alone or in combinations, were used as the substrates for simultaneous production of protease and alpha-amylase by Aspergillus oryzae under solid state fermentation using a simplex centroid mixture design. The substrates with highest water absorption index and more homogeneous granulometric distribution have positively influenced on enzymes production. Synergistic effects of agroindustrial wastes observed on the production of protease and alpha-amylase resulted in increases ranged from 6.3 to 106.1% at 24h fermentation. Mixtures contained wheat bran (1/2) and soybean meal (1/2) or wheat bran (1/2) and cottonseed meal (1/2) may be added to improve the enzymes production in shorter time fermentation. However, at 48 and 72 h fermentation, the most of the interaction effects observed were antagonistic and the highest protease and alpha-amylase activities were obtained wheat bran as the substrate. This innovative process showed maximization of alpha-amylase and proteases production when mixtures were used compared to the isolated substrates and can be extended to other enzymes groups for obtaining multi-enzyme complex. (C) 2013 Elsevier B.V. All rights reserved.