Amylase from Bacillus sp. Produced by Solid State Fermentation Using Cassava Bagasse as Starch Source.

Abstract

Amylases are enzymes involved in starch hydrolysis, generating the most diverse products, such as maltose, glucose and dextrins. This work aimed the study of the production of amylolytic enzymes via solid-state fermentation (SSF) using “crueira”, an essentially starchy cassava residue, as substrate-support and Bacillus sp. as microorganism. For the implementation of the experimental part, a Central Composite Design (CCD) with three variables (initial moisture, pH and temperature) was made. Each test was examined at 24, 48 and 72 hours by the method of starch dextrinizing activity. The optimum production conditions were 60% initial moisture, pH 6 and 37 °C. The maximum yield was 437.76 U/g in 72 hours of fermentation. The optimum temperature of enzyme performance was 65 °C. The pH optimum range was 4 to 6. The Co^{2 +}, Ca^{2 +} and K⁺ ions positively influenced the activity of enzymes and the Fe²⁺ ion had no effect on enzymatic activity. On the other hand, the ions Hg²⁺, Zn²⁺, Cu²⁺, Mn²⁺ and Mg²⁺ adversely influenced enzymatic activity. Therefore, producing amylases from Bacillus sp. and using crueira as a substrate is possible.

Keywords:
amylases; solid-state fermentation; crueira