Avaliação da influência de enzimas hidrolíticas microbianas na degradação dos polímeros polihidroxialcanoatos e poliuretanos

Abstract

Materials obtained from fossil fuels are widely used, mainly due to the mechanical and thermal properties, reliability and durability they offer. On the other hand, the accumulation of these plastics in landfills negatively affects the environment and human health. As an alternative to reduce the disposal of waste in the environment, much research has been carried out in order to reduce the improper disposal of these polymers. The work aims to study the influence of microbial enzymes protease, esterase, lipase and urease on the degradation process of polyurethane (PU) and polyhydroxyalkanoate (PHA) polymers. The polyurethane foams and polyhydroxyalkanoate plastic bags were previously treated, autoclaved and added to specific culture media for the production of each enzyme (protease, lipase, esterase and urease) containing the microorganism Fusarium verticillioides (CCDCA 11547) and Aspergillus oryzae (CCDCA 10203).During the 35 days of incubation, Enzymatic Assays were performed for the enzymes mentioned above, pH and biomass evaluation, and Fourier Transform Infrared (FTIR) to determine the possible compounds generated, present in the liquid content. In addition, Scanning Electron Microscopy (SEM) was performed to analyze the structures of the polymers. The results showed that F. verticillioides and A. oryzae have great potential to act on the degradation of PU and PHA polymers. In all treatments, there was the production of the enzymes of interest, there was mycelial growth during fermentations, and it was possible to see from the SEM images that there was an alteration in the structures of the polymers. The results of the work showed the potential application of microbial enzymes in the polymer degradation process.