Shrimp shells

The preparation of glucosamine hydrochloride from lobster shells and crab shells by essentially this method has been reported by Irvine, McNicoll, and Hynd and Hudson and Dale. Other methods involving the use of cicad larvae shells and shrimp shells ls also have been reported. 

Chitosan is the main structural component of crab and shrimp shells. Chitosan contains both reactive amino and hydroxyl groups, which can be used to chemically alter its properties under mild reaction conditions. Al-acyl chitosans were already reported as blood-compatible materials. UV irradiation grafting technique was utilized to introduce obutyrylchitosan (OBCS) onto the grafted SR film in the presence of the photosensitive heterobifunctional cross-linking agent. The platelet adhesion test revealed that films grafted on OBCS show excellent antiplatelet adhesion. 

Morehouse, K.M. and Desrosiers, M.F. (1993). Electron spin resonance investigations of gamma-irradiated shrimp shell. Appl. Radiat. Isot. 44.429. 

Chitosan is a cationic polysaccharide produced from the deacetylation of chitin, a component of crab and shrimp shells [7,57,58], Chitin is composed of units of 2-deoxy-2-(acetylamino) glucose joined by glycosidic bonds that form a linear polymer. Ilium et al. [7,57,58] demonstrated the ability of chitosan to increase the bioavailability of insulin and other small peptides and polar macromolecules in different animal models. In both the sheep and rat models, the addition of chitosan at concentrations of 0.2%-0.5% to nasal formulations of insulin resulted in significant increases in plasma insulin and reductions in blood glucose. Reversibility studies indicated that the effect of chitosan on the nasal absorption of insulin... 

The crude chitin is isolated from the outer skeletons of crustaceans, molluscs or invertebrate animals, insects, and certain fimgi. Commercially, crab and shrimp shells are the major sources of chitin. Crustacean shells not only consist of 30 0% protein, 30-50% calcium carbonate, and... 

FIGURE 2.10 XRPD patterns for (A) a-chitin from different sources (1) brown shrimp shells, (2) pink shrimp shells, (3) crabs shells, and (4) crayfish shells (B) the corresponding chitosan. 

In the area of renewable materials, bulk oxypropylation of chitin and chitosan has been performed. Chitin and chitosan are abundant natural polymers obtained from shellfish, such as crab shell or shrimp shell. This solvent free reaction yields viscous polyols. Unfortunately, propylene oxide homopolymer is formed as a by-product but is easily separated. It should be noted that care was taken to minimize the risk involved in the use of toxic, flammable propylene oxide (the reagent in this process). 

TABLE 3.4 Proximate composition of shrimp shell and crab (Santhosh and Mathew, 2008)... 

Shrimp shell waste can be economically converted to chitin, a mucopolysaccharide (Santhosh and Mathew, 2008). This marine polysaccharide and its derivatives hold a major part in our lives as medicines, cosmetics, textiles, paper, food, and other branches of industry because of their unique nature in properties such as low toxicity, biocompatibility, hydrophobicity, etc. Hydrolysis of chitin yields a value added product, glucosamine. Carboxymethylchitin is another derivative of chitin, prepared by the carboxymethylation reaction. 

Santhosh, S. and Mathew, P. T. (2008). Preparation and properties of glucosamine and carboxymethylchitin from shrimp shell. J. Appl. Polym. Sci. 107,280-285. 

Chitin is another highly available polysaccharide biopolymer it is derived from the exoskeleton of arthropods (specifically crab and shrimp shells) and formed from repeats of (l,4)-linked V-acetyl-p-D-glucosamine. In its natural form, the chains of... 

Chitosan, a polymer of j8-(I 4)-linked 2-amino-2-deoxy-D-glucose residues, is formed on deacetylation of chitin. As pointed out already, this polysaccharide takes an extended conformation similar to that of cellulose. Deacetylation of chitin is very easily evaluated in view of the NMR spectra, as illustrated in Fig. 24.5. The three polymorphs of chitosan, ten-don-chitosan (from crab shell), L-2 (from shrimp shell), An-nealed (from crab shell chitosan annealed at 22°C in the presence of water) are easily distinguished, consistent with the data for the polymorphs as obtained by a powder X-ray diffraction data [38, 39]. The observed non-equivalence of two chitosan chains, as viewed from the splittings of the C-1 and C-... 

Commercially available pure a-chitins (originating from crab and shrimp shell) can be used as starting material. 

Goodrich, J.D., Winter, W.T. a-Chitin Nanocrystals Prepared from shrimp shells and their specific surface area measurement. Biomactomolecules. 8, 252-257 (2007)... 

Crab and shrimp shell wastes are an abundant source of chitin, a nitrogen atom containing polysaccharide ... 

Nawawi and Hassan (2003) prepared homogeneous (unmodified) and cross-linked chitosan (extracted from shrimp shells) membranes. Chitosan membranes were modified via a chemical cross-linking technique. PV experiments were done using an IPA-water system. From the PV experiments, it was observed that chitosan membranes exhibited preferential permeation to water. The modified chitosan membrane showed a lower permeation flux, but a higher separation factor than the unmodified membranes. The modified chitosan membrane had a better PV performance than the unmodified membranes in terms of a PSI. 

Percot A., Won C., Domard A., Optimization of chitin extraction from shrimp shells. Biomacromolecules, 4, 2003, 12-18. 

This work was supported by the Contract Development at Project to develop innovative seeds from Japan Scientific Technology Agency. The authors thank Prof. George A. F. Roberts for his valuable discussions on production of chitin and chitosan from insect and mushroom. The authors are also thankful to Dr. Kyaw Nyein Aye for the personal interview on his experience on industrial scale production of chitin and chitosan from shrimp shells. 

M. rouxii without shaking, 28°C, 9 or 21 days 13.25% chitin, 12.49% chitosan —/50.(f % for chitin —1195% for chitosan chitos was estimated to be less than those from shrimp shells (2005)... 

Teng et al. (2001) reported that proteolytic fungal fermentation of shrimp shells is a simple, effective, and inexpensive approach of chitin production from shrimp shells and fnngal mycelia. The results suggest that deproteinization and demineralization occnrs nnder those conditions. Sini et al. (2007) reported that Bacillus subtilis is an efficient starter cnltme from fermentation of shrimp shells. About 84% of the protein and 72% of the minerals were ranoved from the fermented residne at the end of fermentation. 

Sini, T. K., Santhosh, S., and P. T. Mathew. 2007. Stndy on the prodnction of chitin and chitosan from shrimp shell hy nsing Bacillus subtilis fermentation. Carbohydrate Research 342 2423-2429. 

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