ANTIFUNGAL CALCIUM ALGINATE MICROPARTICLES CONTAINING Bacillus amyloliquefaciens FOR AGRICULTURE
Along with the great agriculture development, using disease control agents in plants has become essential to increase crop yield production demanded by the last century’s fast-growing human population. Among the many technologies used for pest control, microcapsules containing microbiological control agents. This work aimed to develop sprayable calcium alginate microparticles (smaller than 150 μm) and containing Bacillus amyloliquefaciens. Two experimental designs were carried out to study the two-step relationship of the emulsification process and to optimize the particle size. After choosing the F1, F2, F3 and F4 formulations, the chosen microorganism was microencapsulated in them. The microencapsulation process showed final viable cell counts consistent with commercial product values and the encapsulation efficiency was greater than 90% for all samples. The morphological evaluation showed that the microparticles produced can be microcapsules or microspheres, and that the microorganisms are located inside the particles. The release behavior of the samples was similar and showed the Burst effect in the first hours of release. The viability of microorganisms in the microparticles was evaluated for a period of 30 days resulting in an average loss of 18%. The UV protection test showed that microparticles were effective in protecting against UVB radiation for 60 minutes, resulting in higher final concentrations than blank. However, for UVC radiation the result was inferior to the blank. Finally, the F2 and F4 formulations were efficient in controlling the phytopathogens, completely inhibiting their growth in the plates.