Abstract

                               Spray drying technology is often used as an encapsulation technique by the food and microbe mediated industries. Encapsulation of microorganisms in a polymer matrix as immobilized microbial cells would facilitate such novel formulation. An experiment was conducted to investigate the best water-soluble carriers through encapsulation of Bacillus megaterium var. phosphaticum by spray drying technology. Among the carriers tested malto dextrin and soluble starch produced fine encapsulated powder with high population load of 107 CFU.g-1 and shelf life up to twelve months. Regarding the solubility factor malto dextrin was found to be fully soluble in water and the cells were easily suspended whereas, soluble starch had slight precipitations at the end. Further, in this study it was observed that at optimal nozzle temperature of 120 °C, the malto dextrose encapsulated product resulted with high population followed by nozzle temperature of 110°C. The best bioformulation that supported the survivability in rhizosphere was spray dried products with higher microbial load than liquid formulations and lignite based carriers.

Key words : Phosphorus solubilizing bacteria, Spray dried formulation, Maltodextrose