Dise？o de un medio para la producción de un co？cultivo de bacterias fosfato solubilizadoras con actividad fosfatasa

objective. to design a complex culture media for the production of biomass and acid phosphatases from phosphate-solubilizing bacteria isolated from soil. materials and methods. phosphate-solubilizing bacteria were isolated from oil palm crop soil samples and selected on smrs1 agar, which were then assessed with antagonism tests to verify their aptitude to form a co-culture. a box-behnken experimental design was applied to evaluate the effect of each one of the culture media components on the production of biomass and phosphatase enzymes at a laboratory scale. finally, microbial growth and enzyme production curves were carried out in order to determine their production times. results. five phosphate-solubilizing bacterial strains were isolated and three of them were selected based on their solubilization indices. these gram negative strains with bacillus morphology were identified as a, b and c; their solubilization indices were 2.03, 2.12, and 2.83, respectively. according to the anova analyses for the box-behnken design, the only factor which had a significant effect on the phosphatase activity (p<0.01) was hydrolyzed yeast, and the formulation that generated the highest biomass concentration and phosphatase activity (p<0.01) contained 10, 15 and 2.5 gl-1 of phosphoric rock, sucrose and hydrolyzed yeast, respectively. after 24 hours of incubation at 100 rpm, the highest values of biomass and phosphatase activity were obtained: 11.8 logarithmic units of cfu and 12.9 phosphatase units. conclusion. we determined that the culture media based on phosphoric rock 10 gl-1, hydrolyzed yeast 2.5 gl-1 and commercial sucrose 15 gl-1 was ideal for the production of biomass and phosphatases by the strains evaluated; likewise, we proved that the hydrolyzed yeast was the only factor significantly influential for the production of phosphatases.