3.1. Specific and regioselective enzymatic hydrolysis of
peracetylated-β-d-galactose (1)
Several purified lipases from different sources, immobilized
on agarose activated with CNBr, were studied as catalysts in
the hydrolysis of 1 (Table 2, Scheme 2). We have preferred to
directly study immobilized lipases instead of free enzyme to
prevent possible artifacts due to the strong tendency of lipases
to form bimolecular aggregates with altered properties [26].
The specific activities of the different lipases were very different
against this substrate. The most active catalyst was ANL.
This enzyme displayed 50 times higher specific activity compared
to the second most active, PFL. Other enzymes such as
CAL-B or CAL-A presented around 15 times less activity than
PFL (Table 2). Other lipases were even less active, as it is the
case of RML (around 18,000 times less activity that ANL)