Study of parameters that influence the production of the enzyme CGTase from <em>Bacillus firmus</em>, strain no. 37

Abstract

The cyclodextrins (CDs) are cyclic oligosaccharides formed by residues of glucopyranose linked by α-1,4. The most common are the α-, β- and γ-CD that present 6, 7 and 8 units of glucopyranose, respectively. They are produced from starch by the action of the enzyme cyclodextrin glycosyltransferase (CGTase). Frequently, β-CD is produced in larger amount. A study of optimization of the production of the CGTase from Bacillus firmus, strain no. 37 (β-CGTase) was performed. The production of the enzyme occurred during the phase of exponential growth of the microorganism and the maximum activity was observed within three days of cultivation at 37ºC. The best production of the enzyme was obtained with inoculum of optical density between 0.5 and 1.0 (660 nm). The use of the maltodextrin for production of the enzyme provided an enzymatic activity at 31% lower than the substrate, soluble starch. Therefore, the substrate maltodextrin is not appropriate to improve the production of the studied enzyme.