Biocatalysis - Green Chemistry and Technology - page 197

Fig. 9.19 Routes for the formation of polyesters by catalysis using lipase enzymes.

Fig. 9.20 Enzymic polymerisation of
phenols.

acid established that linking at positions ortho to the
phenol group was the preferred method of polymeri-
sation, but whether this is a general feature remains
to be established [62].

sustainable chemistry [63], and although enzymes
operate in water as their natural environment it is
paradoxical that some of their desirable properties,
such as the ability of hydrolytic enzymes to make
rather than break ester or amide bonds, are only
exhibited under conditions of low water activity,
typically in an organic solvent [64]. This section
will consider an alternative—the use of supercritical
carbon dioxide as a solvent for enzyme reactions—

3 Green Biocatalytic Processes

The replacement of a chemical catalyst by an enzyme
does not per se meet the requirements for green or