[Effect of argillaceous minerals on the growth of phosphate-mobilizing bacteria Bacillus subtilis]

It was shown that the argillaceous minerals montmorillonite and palygorskite at concentrations within 0.2-1.0% considerably accelerate the growth of phosphate-mobilizing bacteria Bacillus subtilis grown in media with hardly soluble Ca3(PO4)2 as the sole source of phosphorus. The most notable effect of these minerals was recorded at concentrations within 0.5-1.0%. The effect of argillaceous minerals in the colloidal form on bacterial growth was more pronounced than that of the powdered ones. An increase in montmorillonite or palygorskite concentrations to 2% is accompanied by the inhibition of the growth of the phosphate-mobilizing strain. At such concentrations the minerals adsorb ca. 22% of the glucose and 11.3% of the phosphate added to the nutrition medium.