Moreover, the effect of ratio (E/A) on the loading efficiency and
immobilization yield is shown in Fig. 1c. Since the beads prepared
in the present work were very small, their loading efficiency might
be relatively limited which would cause a decrease in the immobilization
yield at a higher E/A ratio (1:8). The finding that the
ratio (E/A) of 1:4 was found to be the optimum for the immobilization
of purified laccase from C. gallica can be contrasted with the
reports of Lu et al. (2007), who reported that immobilization of
enzyme by alginate-chitosan microcapsules using a ratio (E/A) of 1/
8 was found to be the best for laccase entrapment.
The optimal conditions were 2% (w/v) sodium alginate, 2% (w/v)
CaCl2 and 1:4 E/A ratio. Under such conditions, the loading efficiency
and immobilized yield of the immobilized laccase were
88.1 2.4% and 93.3 1.1%, respectively.