Expression and functional characterization in yeast of an endoglucanase from Bacillus sonorensis BD92 and its impact as feed additive in commercial broilers

Some ingredients used in poultry feed formulation contain carbohydrate polymers which are difficult to digest and thus hinder nutritional feed value. Toward overcoming this limitation, exogenous enzymes have been added to poultry feed to improve its nutritive value. The present study was designed to provide first enzymatic characterization of endoglucanase (BsEgl) from the genome of B. sonorensis BD92 expressed in Pichia pastoris. Further, we tested its impact alone and in combination with a beta-glucosidase (Bteq beta gluc) on growth in commercial broilers as feed additive. The expressed enzyme displayed features of GH5 family and had optimum activity against carboxymethyl cellulose at pH 5 and 50 degrees C. The BsEgl was stable at a range of pH from 4 to 8 for 60 min and at 50 degrees C for 180 min. Supplementing broilers diet with BsEgl alone or in combination with Bteq beta gluc resulted in better feed conversion ratio among treatments during a five weeks testing period. Moreover, meat percentage was also highest for this treatment, and all treatments with recombinant enzymes increased intestinal length in birds compared to treatment control group. Blood parameters and serum biochemistry profile showed nonsignificant difference among groups. These results support that recombinant cellulolytic enzymes supplement high fiber diets improve their nutritional performance. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Exogenous enzymes such as BsEgl and Bteq beta gluc added to poultry feed can improve the nutritional value of feed, enhance growth performance, and optimize feed conversion ratio. The study results suggest that supplementing high-fiber diets with recombinant enzymes can effectively improve the nutritional performance of poultry, particularly commercial broilers.