Читать книгу Biomolecules from Natural Sources - Группа авторов - Страница 68

Xanthan gum, a complex copolymer produced by a bacterium, one of the first commercially successful bacterial polysaccharides to be produced by fermentation [168, 169]. In terms of production volume, xanthan gum is the most widely used microbial polysaccharide. Worldwide production is currently in the range of 10,000 to 20,000 tons. Xanthans have many applications such as in hydrogel, antibacterial and catalytic applications, in silver nano-particles, in medicinal and pharmaceutical applications [170]. It is used in drug release [171], wound healing [172], blended hydrogels for connective tissue regeneration [173], immobilized biocatalyst [174], edible coatings and many others. Xanthan gum is a HMW extracellular polysaccharide produced by the fermentation of the gram-negative bacterium Xanthomonas campestris. Companies such as ADM and Merck have recently announced the expansion of their xanthan production facilities. About 60% of the xanthan produced is used in foods, with the remaining 40% used in industrial applications. Food-grade xanthan costs about $8 to $10 per pound, while non-food grades sell for about $5 per pound. So far, only experimental samples of genetically modified xanthan have been produced.