Modified chitin as substrate for chitin deacetylase and as adsorbent for wastewater treatment | |
| Author | Karuppuswamy, Renuka |
| Call Number | AIT Thesis no.BT-03-16 |
| Subject(s) | Chitin Sewage--Purification |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. BT-03-16 |
| Abstract | Now a day, lots of wastes are produced from food industries all over the world. Extensive research has been carried out to convert those wastes into useful products. Shrimp is the most valuable seafood product that enters into world trade today. Most of the shrimp is produced as frozen shrimp meat. The shrimp shell produced is used as feed supplement or discarded. Slu·imp shell material (Shrimp bio waste) contains most of the valuable components that can be isolated as long as the biowaste is fresh. These materials are shrimp protein, the natural dye for food including astaxanthin and the major component of the shrimp skeleton; the chitin. The latter is an amino substituted cellulose compound, also referred to as the cellulose of the sea chitin can be converted to chitosan by removal of an acetyl group. Chitosan is a multi purpose product and has many applications, as a cationic biopolymer is really all matches of industry and as a bioactive compound in wound healing and plant growth. For the near future a safe increase in industrial application of chitosan is foreseen. Currently, chitin and Chitosan are manufactured commercially in large scale from the shell of crustaceans (shrimp and crab) by chemical methods by treating with acid and alkali, which result in a high pollution hazard and also the degradation of the product. In order to overcome this problem, an alternative method is indispensable. This is usefully needed to convert the vast amounts of available shellfish waste now for applications require large amounts of chitosan. Researchers have turned their interest towards the production of chitosan by fermentation and by enzymatic methods. For the fermentation of slu·imp biowaste to produce chitin, teclrnology using the bacterium lactobacillus plan/arum is available. The conversion of chitin into chitosan can be achieved by the fungal enzyme chitin deacetylase, but so far this is only demonstrated on laboratory scale. Limitation in the supply of enzyme is one of the constraints. Another constraint is the crystalline structure of the water insoluble chitin that limits the enzyme to access the acetyl groups in the chitin. This study is mainly focused on the increased production and application of the fungal chitin deacetylase enzyme (CDA). This can be accomplished by changing the growth conditions and reaction conditions of the fungi. In this study, Absidia coerulea, Collectotrichum lindemuthianum, Rhizopus 01J1zae, Rhizopus oligosporus and Rhizopus circinans are the fungal strains that are taken as the sources for chitin deacetylase enzyme. The productivity of the enzymatic deacety lation can be improved by rearranging the structure of chitin, thereby providing easy access for the CDA enzyme to react on N-acetyl groups that are present in the chitin polymer chains. Naturally abundant biosorbents such as shellfish chitin and chitosan have been applied successfully for the removal of traces of heavy metals, dyes and radioactive waste. This study also includes the application of modified chitin as a powerful and recoverable adsorbent of dyes in textile wastewater treatment. These modifications also include treating chitin with acetic acid and phosphoric acid. This modified chitin is used as an effective matrix in adsorbing dyes from textile industry wastewater. The characteristics of these modified chitin is studied in detail. |
| Year | 2003 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. BT-03-16 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Stevens, Willem F.; |
| Examination Committee(s) | Suwalee Chandrkrachang;Thammarat Koottatep; |
| Scholarship Donor(s) | Asian Institute of Teclmology The Royal Netherlands Government; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2003 |