Preparation of microcapsules containing antimicrobial lipopeptide from Bacillus amyloliquefaciens ES-2 by spray drying

Using a fermentation broth produced by Bacillus amyloliquefaciens ES-2 as a raw material, a preparation method for antimicrobial lipopeptide powders was developed. Antimicrobial lipopeptide microcapsules were obtained by a spray-drying process using maltodextrin and porous starch as composite wall materials. Optimal encapsulation conditions comprised a ratio of wall materials to the core material of 5%, a ratio of porous starch to maltodextrin of 1/9, a drying air flow of 70 m(3)/h and an inlet gas temperature of 220 degrees C, producing a high yield of microcapsules of 63.9 +/- 0.5%. The lipopeptides retained their desired bioactivity and had a spherical form after spray drying, with an antimicrobial potency of 25711.3 +/- 34.5 IU/g evaluated by the cylinder-plate method, and their preservation percent was about 81.5%. Because of its low cost, high efficiency, simplicity and easy of scale-up, the technology is expected to be efficient for producing antimicrobial lipopeptide powders and to be helpful in the application of antimicrobial lipopeptides as food additives. (C) 2013 Elsevier Ltd. All rights reserved.