Chitin sources

Plant fails to grow and/or flower leaves with swollen spots. Cause Bulb and stem nematodes. Feeding by microscopic round-worms causes deformed leaves with yellow-green spots and small, swollen areas. Bulbs develop dark internal circles or blotches and may fail to grow or bloom in spring. Dig and destroy severely infected bulbs and foliage. Soak mildly infested bulbs in hot (110°F) water for 3 hours, then plunge them immediately into cold water. Let them dry and store in a cool, dark place until fall when they can be replanted. Solarize infected soil or treat with a chitin source. 

Kurita, K., Tomita, K., Ishii, S., Nishimura, S., and Shimoda, K. 1993. Squid chitin A potential alternative chitin source Deacetylation behaviour and characteristics properties. J. Poly. Sci. Part A Poly. Chem. 31, 485-491. 

Pariser, E.R. Chitin Source Book A Guide to the Research Literature, Wiley New York, 1989. 

Figure 2.8 X-Ray diffraction pattern for (powder and film) a-chitin. Source Reproduced with permission from Gonzalez-Campos JB, Prokhorov E, Luna-Barcenas G, Mendoza-Galvan A, Sanchez IC, Nuno-Donlucas SM, Garcia-Gaitan B, Kovalenko Y. J Polym Sci B Polym Phys 2009 47 932 [5]. Copyright 2009 John Wiley and Sons, Inc.

In industrial processes, chitin is extracted from crustaceans by acid treatment to dissolve calcium carbonate followed by alkaline extraction to solubilize proteins. In addition, a decolour-ization step is often applied to remove the residual pigments and to obtain a colourless product. These treatments need to be adapted to each chitin source due to differences in the ultrastructure of the initial materials. 

Commercial chitin is extracted from crustacean wastes of the fishing industry, the main chitin sources being the shells of shrimp, crab, lobster, prawn and krill. These crustacean wastes consist of chitin (20-30 per cent), protein... 

Kurita K., Tomita K., Tada T., Ishii S., Nishimura S.-L, Shimoda K., Squid chitin as a potential alternative chitin source ... 

Kurita, K., Tomita, K., Tada, T., Niscimura, S., and Scimoda, K. (1993) Squid Chitin as a Potential Alternative Chitin Source-Deacetylation Behaviour and Characteristics Properties. J. Polym. Sci., Part A Polym. Chem. 31,485-491. 

On the basis of the above background and viewpoints, this chapter reviews the studies on the preparation of self-assembled CNFs and the following fabrications of chitin-based nanofibrous and nanocomposite materials using the ionic liquid, AMIMBr. The series of the studies provide new approaches for material processing from native chitin sources. 

A. PRODUCTION OF CHITIN/CHITOSAN After cellulose, chitin is the most abundant natural polymer. It is an essential component of the skeletal material of crustacean shells, insect cuticles as well as in cephalopoda and fungi. In the seafood industry, chitin sources are the exoskeletons of shrimp, crab and lobster and also squid pens and cuttlefish bones. The important commercial sources of chitin is crab and shrimp shells. 

Chitin source Time (h) Temp (°C) Length, L (nm) Width, d (nm) Aspect ratio (L/d)... 

For a review of the isolation of chitin from natural sources and some of its uses see the November 1990 issue of the Journal of Chemical Education (pp 938-942)... 

Last years the concern of the scientists and contributors to chitin, chitosan and chitincontaining connections has increased. It is connected to their widespread occurrence in the nature, paiticulai properties, and also feasibility in many areas of a national economy. The raw sources for obtaining chitincontaining of products are the testas of crabs, lobsters, shrimps, and also cabbage-weeds, funguses. 

Because chitin is the most abundant compound of nitrogen, it represents the major source of nitrogen accessible to countless Uving terrestrial and marine organisms. 

In conclusion, it is noteworthy that cyclodextrins, liposomes and chitin derivatives are all readily available from renewable biochemical sources and offer advantages of biodegradability and safety in use. However, it needs to be borne in mind that this fact alone does not necessarily mean that they are entirely environmentally innocuous in the long run. Demands on resources for the husbanding and processing of bioforms that may be necessary in order to sustain demand for commercially viable qualities and quantities can exert deleterious effects, not least because they may give by-products that present problems of utilisation or disposal [70]. 

Chitin and Chitosan Sources, Chemistry, Biochemistry, Biochemistry, Physical Properties and Applications Skjak-Braek, G. Anthousen, T. Sanford, P., Eds. Elsevier Applied Science New York, NY, 1989 835 pp. 

Thus chitin is abunckmt in the sea, in diatom blooms and in the zooplankton, most notably in the shoals of krill and on the land, in invertebrates and in fungi in the soil. Potential industrial sources are wastes from shrimps and crabs, krill, squid, clams and oysters, and fungal fermentations (13). The krUl fishery alone produces 3000 tons per year, currently going to waste. 

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