STATISTICAL OPTIMIZATION OF CELLULASES PRODUCTION FROM A STREPTOMYCES SP. STRAIN

Resumen

The Streptomyces genus is a group of Gram-positive bacteria, which play an important role the decomposition of organic matter through the production of lignocellulolytic enzymes. The aim of the present work was to evaluate the effect of the culture conditions (pH, temperature and stirring speed) on the growth of a wild strain of Streptomyces sp. and the production of cellulases. For this, an experiment was designed with a 33 factorial treatment arrangement with three replications, whose levels were pH: 6.5, 7.5, and 8.5, temperature: 35, 37, and 39°C, and stirring speed: 100, 150, and 200 rpm. The biomass measured was expressed in mg/mL, and the response surface method was used for this variable analysis. Enzymatic activity was evaluated by determining free glucose from cellulose. As optimum values, pH 7.5 and stirring speed of 170 rpm were obtained. There was no temperature effect. The increase in enzyme activity coincided with the biomass increase, with a maximum after 36 hours of incubation. These conditions, as well as the synthesis time, are advantageous from an economic point of view for industrial use. Keywords: Streptomyces sp., cellulases, response surface, biotechnology