Dissertação mest., Engenharia Biológica, Universidade do Algarve, 2009Chiral amines are important building blocks for the pharmaceutical and
agrochemical industry. They have many applications and are therefore of economical
importance. Their production has mostly been achieved by enzymatic resolution.
Aminotransferase, the enzyme most commonly used is known to be a pyridoxal-5-
phosphate (PLP) dependent enzyme and it is commercialized in a spray dried
Escherichia coli formulation.
Since there is a great market for this enzyme and all the products it can synthesize,
it is essential to constantly improve its efficiency and make it even more economically
attractive. Several studies have been conducted to achieve this purpose, one of these
being the reutilization of the biocatalyst by immobilization.
In this work, immobilization of the biocatalyst was performed using a different
approach than what has been tried before.
The approach is based on interaction between hydrous transition metal oxides,
mainly the hydrous titanium oxide (TiOx), and biological entities such as cells, enzymes
and similar. Hydrous titanium oxide has the ability to bind the cells and enzymes via
hydroxyl groups forming partial covalent bonds.
Using this method, the biocatalyst was successfully immobilized and its
reutilization was demonstrated for several batches.
Studies on enzyme kinetics, storage stability, temperature effect, and loading
capacity were performed to validate the usefulness of the immobilization method for the
potential use in a large scale process
