Xanthan, biodegradation

Xanthan Xanthomonas campestris Highly viscous and pseudoplastic gels with galactomannes resistant to acid, alkali and biodegradation oil-well drilling, food industry... 

In addition to the surfactant, a white oil was a component of the microemulsion. This oil was added in the minimum amount required to solubilize enough xanthan polymer to produce the target viscosity. In the absence of the white oil, the polymer could not be solubilized. The xanthan polymer itself was required for mobility control. To prevent biodegradation of the polymer, formaldehyde was added. Citric acid was also a component of the microemulsion, added to prevent the oxidation of ferrous ion present in the brine to ferric ion. The presence of ferric ion would lead to precipitation of iron compounds as well as cross-linking of the biopolymer. 

In an initial experiment, the biodegradability of the eps by a mixed culture was compared to the biodegradability of several commercially available polysaccharides guar gum, locust bean gum, xanthan and soluble starch. The eps contained approximately 30%... 

Chellet R, Tabrizian M., Dumitriu S., Chornet R., Rivard C.H., Yahian L., Study of biodegradation behavior of chitosan-xanthan microspheres in simulated physiological media, J. Biomed. Mater. Res. Part B, 53, 2000, 592-599. 

Bionanocomposites are an ecological alternative to conventional nanocomposites based on petroleum-derived polymers, as they are based on biodegradable polymers obtained from renewable resources. Biomass is the source of agropolymers like starch and cellulose and also of monomers used to chemically synthesize polymers like polylactic acid (PLA). Other kinds of biopolymers, e.g., xanthan gum and poly (hydroxyalkanoates), are produced by microorganisms. Even though most of the bionanocomposites reported in the hterature are based on layered sihcates, the number of examples illustrating the use of fibrous clays in the preparation of new bionanocomposites is growing rapidly. 

Complex carbohydrates such as microbially produced xanthan, curdlan, pullulan, hyaluronic acid, alginates, carageenan, and guar are accepted as biodegradable and are finding uses where cost is not an impediment. Xanthan is the predominant microbial polysaccharide on the market, ca 10,000 tonnes world-wide (Byrom, 1991), and finds use in the food industry and as a thickener in many industrial applications. It is foreseeable that the others will gain acceptance in specialty areas where biodegradabilily is essential. 

Sharma N, Deshpande RD, Sharma D, Sharma RK. Development of locust bean gum and xanthan gum based biodegradable microparticles of celecoxib using a central composite design and its evaluation original research article. Ind Crops Prod. 2016 82 161-70. 

Soares R.M.D., Lima A.M.F., Oliveira R.VB., Pires A.T.N., Soldi V Thermal degradation of biodegradable edible films based on xanthan and starches from different sources, Polym. Deg. Stab. 90(2005)449. 

It is known that enzymes such as protease, hemicellulase, pecdnase, and amylase have very little effect on xanthan. This resistance to enzymatic attack is presumably due to the steric hindrance caused by the trisaccharide side chains and the sugar composition of the side chains. However, xanthan is completely biodegradable, and xanthanase has been reported (5). In addition, xanthan lyase is also known that cleaves the side-chain sugars and may have a role in xanthan degradation (6). The current knowledge of xanthan depolymerizadon is sdll incomplete, and xanthanase is not commercially available. 

W. Hashimoto, Y. Mishima, O. Miyake, H. Nankai, K. Momma, and K. Murata, Biodegradation of alginate, xanthan, and gellan, in Biopolymers Online, Wiley-VCH Verlag GmbH Sc Co. KGaA, 2005. 

Some other biodegradable natural polymers such as dextran," heparin," xanthan," pullulan," " elastin," fibrin," pectin" and hyaluronate," were also investigated as biodegradable polymers in various fields. 

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