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The search for new biomaterials with superior mechanical properties is the focus in the area of materials science. A promising pathway is drawing inspiration from nature to design and develop materials with enhanced properties. In this work, a novel strategy to produce functionalized supramolecular bionanomaterials from the microbial biofilm is reported. Tuneable biofilms with specific characteristics were obtained by controlling the culture condition of the microorganism. When the exopolysaccharide (EPS) production was desired the tryptone was the best nutritional component for the EPS production into the biofilm. However, for the expression of a high amount of amyloid protein the combination of peptone and glucose was the best nutritional choice. Each biofilm obtained showed its owner rheology properties. These properties were altered by the addition of extracellular DNA, which increased the viscosity of the biofilm and induced a viscoelastic hydrogel behavior. Besides, as a proof of concept of bionanomaterial, a novel supramolecular polymeric hybrid EPS-Amyloid protein (EPAP) was obtained from the biofilm and it was tested as a new natural functionalized support for enzyme immobilization. The results suggest that this technology could be used as a new concept to obtain biomaterials from biofilms by controlling the nutritional conditions of a microorganism. Understanding environmental factors affecting biofilm formation will help the development of methods for controlling biofilm production and therefore obtaining new biomaterials.

Biocatalysis for industrial application is based on the use of enzymes to perform complex transformations. However, these systems have some disadvantage related to the costs of the biocatalyst. In this work, an alternative strategy for producing green immobilized biocatalysts based on biofilm was developed.A study of the rheological behavior of the biofilm from Bacillus sp. Mcn4, as well as the determination of its composition, was carried out. The dynamic rheological measurements, viscosity (G") and elasticity (G') module, showed that the biofilm presents appreciable elastic components, which is a recognized property for enzymes immobilization. After the partial purification, the exopolysaccharidewas identified as a levan with a non-Newtonian behavior. Extracellular DNA with fragments between 10,000 and 1000bp was detected also in the biofilm, and amyloid protein in the extracellular matrix using a fluorescence technique was identified. Bacillus sp. Mcn4 biofilms were developed on different surfaces, being the most stable those developed on hydrophilic supports. The biofilm showed lipase activity suggesting the presence of constitutive lipases entrapped into the biofilm. Indeed, two enzymes with lipase activity were identified in native PAGE. These were used as biocatalysts, whose reuse showed a residual lipase activity after more than one cycle of catalysis. The components identified in the biofilm could be the main contributors of the rheological characteristic of this material, giving an exceptional environment to the lipase enzyme. Based on these findings, the current study proposes green and natural biopolymers matrix as support for the enzyme immobilization for industrial applications.