الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 190 |  |  |
| | | from | 190 | | |
Abstract
Chitosan, the deacetylated derivative of chitin, is a linear polymer of β-1, 4-glucosamine units. It is poly-cationic, nontoxic, biodegradable as well as antimicrobial and has been reported to have numerous applications especially in food, pharmaceutics and cosmetics. Commercial production of chitosan by deacetylation of crustacean chitin with strong alkali appears to have limited potential for industrial acceptance because of seasonal and limited supply, difficulties in processing particularly with the large amount of waste of concentrated alkaline solution causing\ environmental pollution and inconsistent physico-chemical properties. With advances in fermentation technology chitosan preparation from fungal cell walls becomes an alternative route for the production of this polymer in an ecofriendly pathway Chitosan prepared from fungi has received much attention, especially from the Zygomycetes species, which are known to contain chitosan as natural components of their cell wall. Among them, the genus Absidia has been reported to produce chitosan feasible for commercial development. The fungal approach has advantage of easy handling, harvesting and control to produce high quality chitosan. The present work was carried out to study the quantitative and qualitative optimization of chitosan production by Absidia coerulea through the following aspects: A. Applying three levels full factorial design to study the effect of different nitrogen sources, glucose concentrations, incubation periods and incubation temperatures on the chitosan production from Absidia coerulea.B. Obtaining quadratic polynomial models for tested factors through response surface methodology (RSM) and Box-Behnken design.C. Evaluation of chitosan production on the bioreactor scale by applying theobtained optimum growth conditions.D. Examining the efficiency of enzymatic bioconversion process of chitin to chitosan
by Alcaligenes chitin deacetylase enzyme.
E. Genotyping identification of the chitin deacetylase producer strain by colony PCR
technique.
F. Partial purification of bacterial chitin deacetylase enzyme.
G. Determining the kinetic parameters of the partially purified enzyme.
H. Examining the efficiency of biocatalyst recycling by immobilization technique.
I. Preparation of chitosan (fungal and crab) – starch based super absorbent
membranes with various concentrations and blend ratios.
J. Evaluating the hemostatic, antibacterial, mechanical, thermal, morphological and
cytotoxic properties of chitosan membranes.