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A. A. Savina, L. S. Garnashevich, I. S. Zaitsev, M. S. Tsarkova, S. Yu. Zaitsev
Changes in the activity of lipaz in the
presence of synthetic and natural polymers
Abstract
Both synthetic and natural polymers are
promising carriers for immobilizing enzymes, including lipases from various
sources. This direction is both of fundamental and applied importance, since
immobilized lipases are widely used in various biotechnological processes. This
work is devoted to study the effect of synthetic and natural polymers
(polystyrene with different surfaces, polylysine, chitosan) on the catalytic
properties of lipases from the hog pancreatic gland (LPP), Candida
Celyndracea (LCC) fungi and wheat germ (LWG) during the hydrolysis of triacetin
(as a substrate in all experiences). It was established that latex based on
polystyrene (even without surface modification) significantly affects the
activity of lipases of different origin, especially in the presence of large
particles of about 1 micron in size (regardless of their concentration in the
range of 1–10%), the activity of all three lipases (LPP, LCC, LWG) is
significantly increased relative to the non-immobilized enzyme. Polystyrene
latex with a carboxylated surface showed another effect on the catalytic
properties of these same lipases. The dependence of the activity of lipase LPP
on the concentration of chitosan (at their ratios from 100:1 to 1:1), as well
as on the parameters of the medium (pH, temperature), was found. Measurement of
the catalytic activity of lipase with polylysine showed that, at their ratios
of 10:1 and 5:1 (excess LPP), there was an increase in the activity of the
enzyme as compared to it free form by 17 and 9%, respectively. This is due to
the interaction of a positively charged polylysine with an enzyme (having an
excess negative charge). The results obtained are promising for use in
biotechnology.
Key words: lipases, polystyrene
microparticles, chitosan, polylysine, catalytic activity.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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