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Green Precipitation with Polysaccharide as a Tool for Enzyme Recovery
Published in Aidé Sáenz-Galindo, Adali Oliva Castañeda-Facio, Raúl Rodríguez-Herrera, Green Chemistry and Applications, 2020
Débora A. Campos, Ezequiel R. Coscueta, Maria Manuela Pintado
These described polysaccharides are very interesting for the industry given the different applications for which they have been studied. Likewise, due to the greater understanding in this field, other anionic polymers can be considered for technological applications. Until now some polysaccharides such as xanthan gum and pectin have been reported. Xanthan gum is a polysaccharide produced industrially by a microbial fermentation of bacterium Xanthomonas campestris involving a carbohydrate substrate and other growth-supporting nutrients. The molecular structure consists of a linear glucose chain linked by β-(1-4) glycosidic bonds like cellulose and possesses a trisaccharide side chain attached through O3 of alternate glucose units in the main chain (Fan and Chen, 2007).
Pharmaceutical Applications of Water-Soluble Polymers in Nanomedicine and Drug Delivery
Published in Shaker A. Mousa, Raj Bawa, Gerald F. Audette, The Road from Nanomedicine to Precision Medicine, 2020
Schuyler A Pruyn, Mehdi Rajabi, Mary Adeyeye, Shaker A. Mousa
Other conventional dosage forms include semi-solid preparations such as ointments, creams, gels, and lotions. These forms often require the use of a thickener or a suspending agent. Polymers function well as excipients in these applications. Xanthan gum, a natural water-soluble polymer, is an effective thickener and stabilizer. It has the unique ability over other polysaccharide solutions to produce highly viscous solutions even at low concentrations. Xanthan gum’s pseudoplastic property improves mouth feel and flavor release, which is why it is commonly used in cosmetics and in toothpastes. Its shear thinning flow behavior allows it to be easily removed from a tube or dispenser, to keep a stable stand on the brush, and to improve the dispersion on and the rinsing from the teeth. The polymer is also used in other gels and creams because its properties allow it to feel soft and gentle.
Pharmaceutical Applications of Water-Soluble Polymers in Nanomedicine and Drug Delivery
Published in Shaker A. Mousa, Raj Bawa, Gerald F. Audette, The Road from Nanomedicine to Precision Medicine, 2019
Schuyler A Pruyn, Mehdi Rajabi, Mary Adeyeye, Shaker A. Mousa
Other conventional dosage forms include semi-solid preparations such as ointments, creams, gels, and lotions. These forms often require the use of a thickener or a suspending agent. Polymers function well as excipients in these applications. Xanthan gum, a natural water-soluble polymer, is an effective thickener and stabilizer. It has the unique ability over other polysaccharide solutions to produce highly viscous solutions even at low concentrations. Xanthan gum’s pseudoplastic property improves mouth feel and flavor release, which is why it is commonly used in cosmetics and in toothpastes. Its shear thinning flow behavior allows it to be easily removed from a tube or dispenser, to keep a stable stand on the brush, and to improve the dispersion on and the rinsing from the teeth. The polymer is also used in other gels and creams because its properties allow it to feel soft and gentle.
Sticky stuff: biological cohesion for scour and erosion prevention
Published in Environmental Technology, 2022
Rob Schindler, Richard Whitehouse, John Harris
Biostabilised substrates were prepared using powdered Xanthan gum, a polysaccharide EPS derived from the bacteria Xanthomonas campestris, and used elsewhere as a proxy for naturally occurring EPS in the laboratory [15,17,18]. Xanthan gum is produced by fermentation based on renewable carbohydrate raw materials, such as glucose syrup, sucrose, or starch. After glucose exhaustion, the culture medium is heat sterilized to kill the Xanthomonas cells and inactivate enzymes produced by the bacterium which would otherwise degrade the polysaccharides and damage xanthan’s rheological properties [30]. Consequently, xanthan is considered biologically inert [31]. It has a large molecular weight (2,000,000 daltons), which is at the upper end of those found in naturally occurring polysaccharides [23]. Xanthan gum shows pseudoplasticity of solution, minimal change of viscosity over a wide range of temperatures, solubility and stability in both acid and alkaline solutions, and viscosity stability over a wide pH range [32] making it a durable product suitable for use in coastal waters.
Preparation and property evaluation of a hydrophobically modified xanthan gum XG-C16
Published in Journal of Dispersion Science and Technology, 2020
Hongping Quan, Yuling Hu, Zhiyu Huang, Duan Wenmeng
Xanthan Gum is a natural polysaccharide produced by fermentation from Xanthomonas campestris. The structure of Xanthan is shown in Scheme 1. The second unit of 1-4-linked-β-(D)-glucose main chain is replaced by a side chain which consists of a D-glucuronic acid alternates with two D-mannoses, the structure above is known as pentasaccharide repeat units.[10–12] The mannose terminally can be acetylated and forms carboxyaldehyde with pyruvate.[13,14] The trisaccharide branches are closely aligned with the glucose backbone, which generate stiff chains exist as an ordered, rigid spiral structure.[15] Another disordered, flexible conformation of Xanthan can exchange to the ordered one under certain condition,[16,17] such as a high ionic strength or at a specific temperature named conformational temperature (Tm).[18]
Enhancing foam stability in porous media by applying nanoparticles
Published in Journal of Dispersion Science and Technology, 2018
Shengbo Wang, Changlong Chen, Mohannad J. Kadum, Bor-Jier Shiau, Jeffrey H. Harwell
Synthetic and biopolymers have been commonly applied in both the environmental remediation and petroleum industries to alter viscosity, improve sweep efficiency, and enhance the recovery of organic liquids from various geological formations.[7] The two polymers used were a biopolymer, Xanthan Gum, supplied by CP Kelco (Atlanta, Georgia, US) and one synthetic cellulose polymer, HEC-10. The HEC-10 is 86 wt% active and was purchased from Sigma Aldrich, St. Louis, MO, USA. Xanthan Gum, which is commonly used in the food industry as a food additive and a stabilizer, is produced biologically by the fermentation of glucose, sucrose, or lactose. HEC-10 is used as a viscosity modifier and stabilization agent in a variety of industries ranging from beauty products to oil and gas production. The details about polymers are shown in Table 1.