Síntese de ABE pela fermentação de Clostridium acetobutylicum encapsulada em alginato e líquido iônico

Abstract

Alternative fuels to petroleum derivatives, such as biofuels, are of great economic importance, since there is the depletion of fossil matter, the basis of conventional fuels. The ABE process (acetone, butanol and ethanol) is an energy matrix that can be produced by fermentative methods that do not harm the environment; For this, several researches use microorganisms such as Clostridium acetobutylicum to produce this matrix. One of the major problems of ABE production by these microorganisms is due to the fact that the fermented product is toxic to them when in high concentrations, highlighting the need for methods that make them more resistant to this toxicity, or that there is no contact of the product with the product. microorganism. Encapsulation is a method that avoids the direct contact of the microorganism with the produced ABE, since in producing it expels the ABE to the external environment (outside the capsules). The objective of this work is the evaluation of ABE production through Clostridium acetobutylicum encapsulated in beads. The use of encapsulation methods is widely used in various industries, being easy to apply and reproduce. Usually alginate and calcium carbonate are used to create the capsules, another method is the use of ionic liquids which may be more promising because it can be recovered for reuse. The capsules are used to immobilize the microorganism in a sphere, whose main function is to protect it. ABE production through encapsulation methodology showed good results compared to traditional (non-immobilized) fermentative methods, with ethanol production higher than expected, but butanol production was slightly lower than that found in other methods. Such differences bring the possibility of future studies of production kinetics. After the first fermentation step, it was possible to reuse the capsules for future fermentation processes, unlike traditional fermentation, where it is necessary to inoculate new microorganisms to restart the process.