Chitin agriculture

Chitosan, the most abundant marine mucopolysaccharide, is derived from chitin by alkaline deacetylation, and possesses versatile biological properties such as biocompatibility, biodegradability, and a non-toxic nature. Due to these characteristics, considerable attention has been given to its industrial applications in the food, pharmaceutical, agricultural, and environmental industries. Currently, chitosan can be considered as a potential marine nutraceutical because its remarkable biological activities have been investigated and reported, in order to exploit its nutraceutical... 

Kjartannson, G.T., S. Zivanovic, K. Kristbergsson and J. Weiss, Sonication-Assisted Extraction of Chitin from Shells of Fresh Water Prawns, Journal of Agriculture and Food Chemistry, 54, 3317-3323 (2006). 

These are haloaromatic substituted ureas which controls insects by impairing chitin deposition in the larval exoskeleton. They are formulated in wettable powders, oil dispersible concentrates, and granules for in agriculture and forestry and in settings where fly populations tend to be large, such as feed-lots. 

Polyoxins are peptide-nucleosides that are substrate analogs of UDP-N-acetylglucosamine wliich is the essential building block of chitin, this polymer making up 1% of the yeast cell wall. Polyoxins have been used in agriculture for many years and act by inhibiting chitin synthetase. 

Since diflubenzuron toxicity seems to be similar in both insects and cmstaceans, extreme care must be taken when this compound and other chitin synthesis inhibitors are used for insect control in areas where aquatic crustaceans occur. Otherwise, ecological instability may result, with consequences for feeding, metabolism, growth, reproduction, and survival of numerous nontarget organisms. Specifically, diflubenzuron use in salt marsh mosquito breeding areas or on agricultural lands less than 5 km from coastal areas is not recommended because of concerns that runoff may reach the adjacent estuaries, which are the primary hatcheries... 

Chitin and chitosan(s) (CS) are biopolymers that have received considerable attention due to their numerous applications in agriculture, food, textile, the paper industry, the food industry and biomedicine and so on. 

Unlike higher organisms, fungi are under high internal pressure and they burst if the cell-wall chitin is removed (e.g. with chitinase, obtainable from snails), unless the osmotic pressure of the medium is increased. Pentachloro-nitrobenzene (quintozene), a commercial agricultural fungicide, produces mycelial walls deficient in chitin (Macris and Georgopoulis, 1969). 

Struszczyk H., Pospieszny H., Kotlinski K., Some new applications of chitosan in agriculture, in Chitin and Chitosan Sources, Chemistry, Biochemistry, Physical Properties and Applications, Eds. Brrek G.S., Anthonsen T. and Sandford P, Elsevier Applied Sci., London, 1989, pp. 733-742. 

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