It is becoming clear, now more than ever, that the human impact on our environment
throughout history has been less-than-stellar. In recent years the problem is becoming exponentially
more apparent, and science is looking to turn to alternative and greener methods of already known
industrial processes. At the same time, molecules that were previously treated as industrially
insignificant are receiving newfound attention from scientists. One example of those molecules is
lignin, which is attracting the scientific world with its broad spectrum of industrial applications. As a
natural source of many important aromatic compounds that have application potential in many
fields of science, lignin depolymerization is a process that could hopefully have a significant impact
on industry as we know it today. While lignin depolymerization certainly has its challenges, we can
turn – once again – to nature for help; there are organisms that are capable of depolymerizing lignin
to aromatic monomers via enzymatic route and those monomers can also be converted further with
the help of enzyme catalysis, which is much more environmentally friendly compared to chemical
catalysis, especially when treating it on an industrial scale. High-value chemicals that can be
obtained from lignin macromolecule are mostly biochemicals and biofuels, however there are
several other fields of science where they can be used and as such the application potential of lignin
is becoming increasingly attractive for scientists. This thesis offers a theoretical background of said
problem, while later in the experimental section it focuses on preparing enzyme and acid samples,
which were than subjected to HPLC analysis. The latter determined the successfulness of
esterification reactions and their conversion of lignin model compounds to ester products. Two
model compounds that were the subject of closer study were eugenol and 2-methoxy-4-
propylphenol. While the results of HPLC analysis were not as good as hoped, especially when it came
to enzyme catalysis, the application potential remains high, as there are several improvements that
can be utilized to increase the conversion rate of studied esterification reactions. Combined with
enzymatic biocatalysts lignin could very well become an important alternative source and could – if
only slightly – mitigate the increasingly looming environmental problem.
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