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Welan Gum
Welan gum is an exopolysaccharide used as a rheology modifier in industrial applications such as cement manufacturing. It is produced by fermentation Fermentation is a type of anaerobic metabolism which harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and reduce ... of sugar by bacteria of the genus '' Alcaligenes''. The molecule consists of repeating tetrasaccharide units with single branches of L-mannose or L-rhamnose. In solution, the gum retains viscosity at elevated temperature, and is stable in a wide pH range, in the presence of calcium ion, and with high concentration of glycols. See also * Gellan gum * Xanthan gum References External links * Polysaccharides Natural gums {{organic-chem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exopolysaccharide
Extracellular polymeric substances (EPS) are natural polymers of high molecular weight secreted by microorganisms into their environment. EPS establish the functional and structural integrity of biofilms, and are considered the fundamental component that determines the physicochemical properties of a biofilm. EPS in the matrix of biofilms provides compositional support and protection of microbial communities from the harsh environments. Components of EPS can be of different classes of polysaccharides, lipids, nucleic acids, proteins, lipopolysaccharides, and minerals. Components EPS are mostly composed of polysaccharides (exopolysaccharides) and proteins, but include other macromolecules such as DNA, lipids and humic substances. EPS are the construction material of bacterial settlements and either remain attached to the cell's outer surface, or are secreted into its growth medium. These compounds are important in biofilm formation and cells' attachment to surfaces. EPS constit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rheology
Rheology (; ) is the study of the flow of matter, primarily in a fluid (liquid or gas) state but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applied forcRheology is the branch of physics that deals with the deformation and flow of materials, both solids and liquids.W. R. Schowalter (1978) Mechanics of Non-Newtonian Fluids Pergamon The term '' rheology'' was coined by Eugene C. Bingham, a professor at Lafayette College, in 1920 from a suggestion by a colleague, Markus Reiner.The Deborah Number The term was inspired by the aphorism of Heraclitus (often mistakenly attributed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fermentation (biochemistry)
Fermentation is a type of anaerobic metabolism which harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and reduced by donating their electrons to other organic molecules (cofactors, coenzymes, etc.). Fermentation is important in several areas of human society. Humans have used fermentation in the production and preservation of food for 13,000 years. It has been associated with health benefits, unique flavor profiles, and making products have better texture. Humans and their livestock also benefit from fermentation from the microbes in the gut that release end products that are subsequently used by the host for energy. Perhaps the most commonly known use for fermentation is at an industrial level to produce commodity chemicals, such as ethanol and lactate. Ethanol is used in a variety of alcoholic beverages (beers, wine, and spirits) while lactate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcaligenes
''Alcaligenes'' is a genus of Gram-negative, aerobic, rod-shaped bacteria in the order of Burkholderiales, family Alcaligenaceae. History The type species, ''A. faecalis'', was first isolated from stale beer by Johannes Petruschky in 1896. However, formal description was only finished in 1919 by Castellani and Chalmers. The name ''Alcaligenes'' has its origin in Arabic and Greek and means "alkali-producing". Several species were previously placed in ''Alcaligenes'', but have since been moved to more appropriate genera. '' A. aestus'', ''A. aquamarinus'', '' A. cupidus'', '' A. pacificus'' and '' A. venustus'' were first reclassified to the genus '' Deleya'' and later merged into ''Halomonas'' in the class of Gammaproteobacteria. Other species were reassigned within the order of Burkholderiales. '' A. denitrificans'', '' A. piechaudii'', '' A. ruhlandii'' and '' A. xylosoxidans'' are currently placed in '' Achromobacter'', '' A. latus'' in '' Azohydromonas'', '' A. eutrophus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L-mannose
Mannose is a sugar with the formula , which sometimes is abbreviated Man. It is one of the monomers of the aldohexose series of carbohydrates. It is a C-2 epimer of glucose. Mannose is important in human metabolism, especially in the glycosylation of certain proteins. Several congenital disorders of glycosylation are associated with mutations in enzymes involved in mannose metabolism. Mannose is not an essential nutrient; it can be produced in the human body from glucose, or converted into glucose. Mannose provides 2–5 kcal/g. It is partially excreted in the urine. Etymology The root of both "mannose" and "mannitol" is manna, which the Bible describes as the food supplied to the Israelites during their journey in the region of Sinai. Several trees and shrubs can produce a substance called manna, such as the "manna tree" (''Fraxinus ornus'') from whose secretions mannitol was originally isolated. Structure Mannose commonly exists as two different-sized rings, the pyranose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L-rhamnose
Rhamnose (Rha, Rham) is a naturally occurring deoxy sugar. It can be classified as either a methyl-pentose or a 6-deoxy-hexose. Rhamnose predominantly occurs in nature in its L-form as L-rhamnose (6-deoxy-L-mannose). This is unusual, since most of the naturally occurring sugars are in D-form. Exceptions are the methyl pentoses L-fucose and L-rhamnose and the pentose L- arabinose. However, examples of naturally-occurring D-rhamnose are found in some species of bacteria, such as ''Pseudomonas aeruginosa'' and ''Helicobacter pylori''. Rhamnose can be isolated from buckthorn (''Rhamnus''), poison sumac, and plants in the genus ''Uncaria''. Rhamnose is also produced by microalgae belonging to class Bacillariophyceae (diatoms). Rhamnose is commonly bound to other sugars in nature. It is a common glycone component of glycosides from many plants. Rhamnose is also a component of the outer cell membrane of acid-fast bacteria in the ''Mycobacterium'' genus, which includes the organism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gellan Gum
Gellan gum is a water-soluble anionic polysaccharide produced by the bacterium '' Sphingomonas elodea'' (formerly ''Pseudomonas elodea'' based on the taxonomic classification at the time of its discovery). The gellan-producing bacterium was discovered and isolated by the former Kelco Division of Merck & Company, Inc. in 1978 from the lily plant tissue from a natural pond in Pennsylvania. It was initially identified as a gelling agent to replace agar at significantly lower concentrations in solid culture media for the growth of various microorganisms. Its initial commercial product with the trademark as Gelrite gellan gum, was subsequently identified as a suitable agar substitute as gelling agent in various clinical bacteriological media. Chemical structure The repeating unit of the polymer is a tetrasaccharide, which consists of two residues of D-glucose and one of each residues of L- rhamnose and D-glucuronic acid. The tetrasaccharide repeat has the following structure: D-Glc(� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthan Gum
Xanthan gum () is a polysaccharide with many industrial uses, including as a common food additive. It is an effective thickening agent and stabilizer that prevents ingredients from separating. It can be produced from simple sugars by fermentation and derives its name from the species of bacteria used, '' Xanthomonas campestris''. History Xanthan gum was discovered by Allene Rosalind Jeanes and her research team at the United States Department of Agriculture and brought into commercial production by CP Kelco in the early 1960s under the trade name Kelzan, remaining the only manufacturer in the US. It was approved for use in foods in 1968 and is accepted as a safe food additive in the US, Canada, European countries, and many other countries, with E number E415 and CAS number 11138-66-2. Xanthan gum derives its name from the species of bacteria used during the fermentation process, '' Xanthomonas campestris''. Uses The addition of 1% xanthan gum can produce a significant incr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysaccharides
Polysaccharides (), or polycarbohydrates, are the most abundant carbohydrates found in food. They are long-chain polymeric carbohydrates composed of monosaccharide units bound together by glycosidic linkages. This carbohydrate can react with water (hydrolysis) using amylase enzymes as catalyst, which produces constituent sugars (monosaccharides or oligosaccharides). They range in structure from linear to highly branched. Examples include storage polysaccharides such as starch, glycogen and galactogen and structural polysaccharides such as hemicellulose and chitin. Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit. Depending on the structure, these macromolecules can have distinct properties from their monosaccharide building blocks. They may be amorphous or even insoluble in water. When all the monosaccharides in a polysaccharide are the same type, the polysaccharide is called a homopolysaccharide or homoglycan, but when more t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
