Optimization of culture conditions for phosphate solubilizing by Acinetobacter calcoaceticus YC5a using response surface methodology
Keywords:
Phosphate solubilizing, Acinetobacter calcoaceticus, medium optimization, response surface.Abstract
Response surface methodology was employed to optimize the composition of medium for phosphate
solubilization by Acinetobacter calcoaceticus YC -5a, which is less well known as phosphate
solubilizing plant-associated bacteria. (NH4)2SO4, Ca3(PO4)2 and KCl were found to have significant
effects on phosphate solubilization by the Plackett -Burman design. The steepest ascent method was
used to access the optimal region of the medium composition, followed by an application of response
surface. The analysis revealed that the optimum values of the tested variables were (NH4)2SO4 0.2 g/L,
Ca3(PO4)2 12.98 g/L and KCl 0.49 g/L, respectively. Phosphate solubilization of 747.72 mg/L, which was
in agreement with the prediction, was observed in verification experiment. In comparison to the original
level (405.4 mg/L), 1.83-fold increase had been obtained.
