|
Abstract
|
Cellulases are third industrial enzymes in the world. Endoglucanases have received considerable attention among
cellulases family, because they cut internal amorphous sites in the cellulose polysaccharide Chain randomly and
generate substrates for cellobiohydrolase and β-glucosidase enzymes to complete the hydrolysis of cellulose. The
cellulases are widely used in textile, detergent, paper industry and biofuel production. Enzyme immobilization
on support is the best technique among different method for enzymatic stabilization. An advantage of
immobilization is enzymatic reusability, which have an economical advantage for enzyme using in industry.
Chitosan is polycationic support that is deacetylated form of chitin. Due to its unique biological properties such
as biocompability, biodegradability and affordability, chitosan is an attractive support for immobilization. In this
investigation, expression vector that contains the sequence encoding AaCel9A enzyme was transferred into
expression host. After enzyme expression and purification, the enzyme was immobilized on chitosan
macrobeads. Glutaraldehyde used as a cross-linker between enzyme and support. Biochemical properties like
optimum pH and temperature properties of immobilized enzyme were investigated. The study of temperature
profile shows that the immobilized enzyme has higher activity over a wide range of temperatures compared to
the free form of enzyme. Moreover, optimal pH of the immobilized enzyme shift to basic pH relative to the free
form of enzyme.
|