Bacterial cellulose chitin

There are several kinds of natural biodegradable polymers in addition to bacterial PHAs, such as proteins, nucleic acids and polysaccharides. Among them, particulary important polymers such as industrial materials are polysaccharides, such as starch, cellulose, chitin and chitosan. The solid-state structure and properties of starch and amylose [127], cellulose [128] and chitin... 

This chapter gives a general introduction to the book and describes briefly the context for which the editors established its contents and explains why certain topics were excluded from it. It covers the main raw materials based on vegetable resources, namely (i) wood and its main components cellulose, lignin, hemicelluloses, tannins, rosins and terpenes, as well as species-speciflc constituents, like natural rubber and suberin and (ii) annual plants as sources of starch, vegetable oils, hemicelluloses, mono and disaccharides and algae. Then, the main animal biomass constituents are briefly described, with particular emphasis on chitin, chitosan, proteins and cellulose whiskers from molluscs. Finally, bacterial polymers such as poly(hydroxyalkanoates) and bacterial cellulose are evoked. For each relevant renewable source, this survey alerts the reader to the corresponding chapter in the book. 

Animal biomass. Vegetal biomass. Wood, Cellulose, Lignins, Hemicelluloses, Natural rubber, Suberin, Tannins, Rosins, Terpenes, Annual plants. Starch, Vegetable oils, Hemicelluloses, Mono and disaccharides, Polylactic acid. Algae, Chitin, Chitosan, Proteins, Cellulose whiskers. Bacterial polymers. Poly (hydro xyalkanoates). Bacterial cellulose... 

Ciechafiska, D., Struszczyk, H., Kazimierczak, J., Guzinska, K. and Czapnik, M., Novel Bacterial Cellulose/Chitosan Wound Heating Dressing Materials, Monograph, Advances in Chitin Sciences, EUCHIS 04 (in press). 

Natural Polymers Polysaccharides—as bacterial cellulose, dextrin, chitosan, chitin, alginate—and proteins—as collagen, fibrin, silk, elastin Provides innate biological guidance to cells, which favors cell attachment and promotes chemotactic responses Stoppel et al. (2015), Barsotti et al. (2011), and Uleiyetal. (2011)... 

As I have already indicated, the polymeric carbohydrate materials available from natural sources include gums, starch and dextrins, cellulose, hemicellulose, chitin, and bacterial polysaccharides. 

Polysaccharides are the most abundant group of biopolymers on earth, since they make up a large proportion of all plant life, and they also form a major part of many marine and bacterial organisms. The two major plant polysaccharides of interest are cellulose and starch, but chitin, which forms the... 

It is found as a component of fungal and bacterial cell-walls, in insect cuticles, and as the shell of crustaceans. Being so similar to cellulose in chemical composition, its structure is important, if for no other reason than that comparison of the two structures might aid in our understanding of each. The similar fibrillar fine-structure (see Fig. 12) of these two polysaccharides is noteworthy, as the lateral forces between molecules are different. Although chitin does not occur in Nature specifically as a fiber, it is frequently found well-oriented in bristles and as tendon material. Samples from invertebrates are usually admixed with protein and carbonate, both of which must be removed before x-ray diagrams of high quality can be obtained. 

Chi tin is a substance of considerable biological importance. It consists of (l->-4)-6-D-g 1 ucose chains with every C(2) substituted by an acetylamino group.(1 ) It is found, as a component of fungal and bacterial cell walls, in insect cuticles and in the shell of crustaceans. (1 ) Like cellulose, it occurs in more than one crystal form anda-chitin, which is more common than e-chitin, is the form encountered in fungi. 

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