Industrial Biotransformations

138
5 Basics of Bioreaction Engineering
-
CH2OH O3SO O
OH
OH
O
O
O O
OH
n = 250-2000
+
Fig. 5.13 k-Carrageenan gel formation.
E
E E
E
E E
E
E
E
E
E
E
K +
K +
K +
K+
K+
K +
K +
E E
An often-used synthetic immobilization method employs polyacrylamide gel. The biocatalyst,
a monomer (acrylamide) and a cross-linker (e.g., N,N′-methylenebisacrylamide)
are mixed and polymerized by starting the reaction with an initiator (e.g., potassium persulfate)
in the presence of a stimulator (e.g., 3-dimethylamino propionitrile) (Fig. 5.14).
O
NH 2
1 = acrylamide
2 = N,N'-methylenebisacrylamide
3 = enzyme
4 = polyacrylamide gel
H H
N N
+ +
O O
1 2
3
O
O
NH
NH
Fig. 5.14 Polyacrylamide gel formation.
O
CONH2 CONH2 O
HN H2N E
CONH 2
HN
O
O
NH NH
4
O
E
initiator
stimulator
E