Simultaneous production of amylases and proteases by Bacillus subtilis in brewery wastes

作者：Sanchez Blanco Alina; Palacios Durive Osmar; Batista Perez Sulema; Diaz Montes Zoraida; Perez Guerra Nelson

来源：Brazilian Journal of Microbiology, 2016, 47(3): 665-674.

DOI：10.1016/j.bjm.2016.04.019

• Amylases
• Bacillus subtilis
• Brewery wastes
• Proteases
• Response surface methodology

The simultaneous production of amylase (AA) and protease (PA) activity by Bacillus subtilis U0-01 in brewery wastes was studied by combining the response surface methodology with the kinetic study of the process. The optimum conditions (T= 36.0 degrees C and pH = 6.8) for high biomass production (0.92 g/L) were similar to the conditions (T= 36.8 degrees C and pH = 6.6) for high AA synthesis (9.26 EU/mL). However, the maximum PA level (9.77 EU/mL) was obtained at pH 7.1 and 37.8 degrees C. Under these conditions, a considerably high reduction (between 69.9 and 77.8%) of the initial chemical oxygen demand of the waste was achieved. In verification experiments under the optimized conditions for production of each enzyme, the AA and PA obtained after 15 h of incubation were, respectively, 9.35 and 9.87 EU/mL. By using the Luedeking and Piret model, both enzymes were classified as growth-associated metabolites. Protease production delay seemed to be related to the consumption of non-protein and protein nitrogen. These results indicate that the brewery waste could be successfully used for a high scale production of amylases and proteases at a low cost.

• 出版日期2016-9