Producción y caracterización de sustancias poliméricas extracelulares EPS a diferentes tiempos de crecimiento utilizando microorganismos Acidófilos

Abstract

This research focused on the determination of the best microbial growth time for the production of extracellular polymeric substances (EPS), since these substances play an important role in the biooxidation of gold refractory minerals. The microorganisms used were Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans, which were managed under conditions of pH 1.8 and 1.3 temperature 30 ° C and were cultivated at different times of microbial growth, such as at maximum growth time, 72 and 96 hours, beside these were adapted to inducers for a greater production of EPS, which were galactose at concentrations of 0, 0.15, 0.25 and 0.35% and ferric ion at concentrations of 9, 18, 27 and 36 g / L respectively. The highest production of EPS in cultures of Acidithiobacillus thiooxidans occurred at a time of 72 hours using galactose as inducer at a concentration of 0.25%, while for the cultures of Leptospirillum ferrooxidans the highest production of EPS was given in 48 hours using iron as inducer at a concentration of 27 g / L.