Surimi wash water treatment by chitosan-alginate complexes

producing a fully deacetylated chitosan (Bouriotis and others, 2002). Kolodziejska
and others (2000) recommend using a two-stage chemical and enzymatic process
with deacetylation in a hot NaOH solution used first to ensure full solubilization of
chitin and followed by enzymatic deacetylation that can be performed by using
deacetylase extracts from Mucor rouxii mycelium. Crude deacetylase extract acting
on a 0.25% substrate solution with initial degree of deacetylation 68% achieved
90% deacetylation in 6 h. A higher substrate concentration (1.2%) resulted in only
85% deacetylation in 10 h. The use of crude enzyme extracts containing
chitosanolytic and chitinolytic enzymes leads to partial hydrolysis of the
polysaccharide resulting in lower viscosity. Therefore, to obtain highly viscous
chitosan, a purified enzyme should be used (Kolodziejska and others, 2000).
2.5. Applications
Chitin and its derivatives are broadly used in medicine, food and cosmetics
industry, agriculture and other areas due to properties such as biocompatibility,
biodegradation, biological activity, non-toxicity, non-allergenic and ability for fiber
and film formation (Table 1).
2.5.1. Antimicrobial activity
The exact mechanism of the antimicrobial activities of chitosan, chitin and
their derivatives is still unknown. One of the mechanisms proposed (Shahidi and
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