Multienzyme production by Bacillus velezensis strains isolated from fruit residues in submerged fermentation using triticale and sugarcane bagasse in the cultivation media

The production of multienzymes complex that could act in different raw materials is needed to improve the bioethanol production process. We isolated bacteria from vegetable residues, identified as Bacillus velezensis (UPF-B1 and UPF-B2), which were able to simultaneously produce amylolytic and cellulolytic enzymes. The enzyme complex was produced by submerged fermentation in a media containing whole-grain triticale flour and sugarcane bagasse at pH 5.5 without supplementation with micronutrient solutions, reducing the media's costs. The combined use of raw materials (triticale and sugarcane bagasse) led to higher enzymatic activities, which is important given the need for the availability of raw materials for the industrial operation of enzyme and bioethanol production plants. The enzymes produced by UPF-B1 showed their optimum at pH 5.0-5.5 and 40 ºC, and those produced by UPF-B2 at pH 5.0-5.5 and 30-50 ºC. The multienzyme complex produced by the strain UPF-B2 allows the hydrolysis in mild temperatures, near to those of fermentation processes, avoiding the need for thermophilic yeasts in the fermentation step, being a desirable option to be used in simultaneous saccharification and fermentation processes of bioethanol production.