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This paper reports the production of ivermectin (IVM)‐encapsulated lecithin/poly (methyl methacrylate) (PMMA) nanoparticles via supercritical antisolvent system (SAS). Of a total of nine formulations, experimental condition R7 containing 10% lecithin relative to polymer (PMMA) resulted in the smallest average experimental particle diameter (dexp), more stable surface charges and high IVM encapsulation efficiency (75.9 ± 2.5%). Nanoparticles were morphologically, thermally, and conformationally characterized using scanning electron microscopy (SEM), thermogravimetric analysis/thermogravimetric derivative (TGA/DTG), and Fourier transform infrared–attenuated total reflectance (FTIR/ATR) techniques. In vitro release test showed that the drug has a controlled release of approximately 110 h. Peppas–Sahlin model (R2 = 0.99) was able to describe the diffusion of the drug correctly. Cytotoxicity analysis showed high compatibility of nanoparticles with epithelial cells, fibroblasts, and macrophages. Population balance equation was used to determine kinetic parameters from experimental data of average particle diameter. Synthesized nanoparticles showed high solution stability, good encapsulation capacity, and showed no adverse effects on cell viability, indicating their high potential as a new IVM carrier system for veterinary medicine and human applications.

The process described in the present work uses air supplementation in a fluidized bed reactor containing Bacillus firmus strain 37 immobilized on active bovine bone charcoal, to produce by batch fermentation the enzyme CGTase (cyclomaltodextrin-glucanotransferase). Three different aeration rates were evaluated. The maximum CGTase activity was achieved after 120 hours of fermentation with aeration rate of 2 vvm and was equal to 2.48 U/mL. When 0.5 and 1 vvm were used the enzymatic activities achieved 1.1 and 0.57 U/mL, respectively. Bovine bone charcoal was characterized in terms of surface area, pore size and volume. To the best of our knowledge, the immobilization of microorganism cells in bovine bone charcoal for CGTase production has not been reported in the literature. Our results showed that fluidized bed reactor allows retaining high concentration of biomass, improving biomass-substrate contact and operation at low residence times, which resulted in improved enzyme production. Therefore, the process as proposed has great potential for industrial development.