Spray drying of cellulases produced by Bacillus sp. SMIA-2

Microbial cellulases present biotechnological potential to be used in several industries, including food, brewery and wine, industrial waste for chemical feedstock, animal feed, pulp and paper, agriculture, textile and detergent production. In this work, cellulases produced by the thermophilic Bacillus sp. SMIA-2 in submerged cultures containing sugarcane bagasse, corn steep liquor and passion fruit rind flour were spray-dried, in an attempt to improve their stability for industrial purposes. The cellulases were spray dried and analyzed before and after the drying process and subsequent storage. A Central Composite Design (CCD) 23 was used to investigate the effect of different concentrations of arabic gum and microcrystalline cellulose, as well as the spray dryer inlet temperature on the cellulase spray drying process. The results evidenced that the combination of 1.0 % (w/v) arabic gum and 1.0% (w/v) microcrystalline cellulose, at inlet temperature of 70 °C, was effective in maintaining the activities of both avicelases (avicel-hydrolyzing enzymes) and carboxymethylcellulases (carboxymethylcellulose-hydrolyzing enzymes - CMCase). The dried avicelase was completely preserved when stored at 5oC, while the CMCase retained 89% of its activity, which indicates promising potential for industrial uses, especially in detergent formulations.