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Xylonic Acid
Xylonic acid is the organic compound with the formula . It is an oxidized derivative of xylose. Xylonic acid is a colorless, water-soluble solid. Several isomers are known, all being classified as sugar acids, several of which can be obtained by oxidation of the corresponding pentoses. The C-2 epimer of xylonic acid is known as lyxonic acid. Like other sugar acids, xylonic acid readily converts to a lactone ( RN 15384-37-9) by dehydration. Lyxonic acid behaves similarly. Genetically engineered '' Pseudomonas fragi'' converts D-xylose to D-xylonic acid. Decarboxylation of the xylonic acid by a strain of ''Escherichia coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly fo ...'' give 1,2,4-butanetriol, which is of commercial interest. References Sugar acids Monosaccharides [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xylose
Xylose ( , , "wood") is a sugar first isolated from wood, and named for it. Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes an aldehyde functional group. It is derived from hemicellulose, one of the main constituents of biomass. Like most sugars, it can adopt several structures depending on conditions. With its free aldehyde group, it is a reducing sugar. Structure The acyclic form of xylose has chemical formula . The cyclic hemiacetal isomers are more prevalent in solution and are of two types: the pyranoses, which feature six-membered rings, and the furanoses, which feature five-membered rings (with a pendant group). Each of these rings is subject to further isomerism, depending on the relative orientation of the anomeric hydroxy group. The dextrorotary form, -xylose, is the one that usually occurs endogenously in living things. A levorotary form, -xylose, can be synthesized. Occurren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isomer
In chemistry, isomers are molecules or polyatomic ions with identical molecular formula – that is, the same number of atoms of each element (chemistry), element – but distinct arrangements of atoms in space. ''Isomerism'' refers to the existence or possibility of isomers. Isomers do not necessarily share similar chemical property, chemical or physical property, physical properties. Two main forms of isomerism are structural isomerism, structural (or constitutional) isomerism, in which ''chemical bond, bonds'' between the atoms differ; and stereoisomerism (or spatial isomerism), in which the bonds are the same but the ''relative positions'' of the atoms differ. Isomeric relationships form a hierarchy. Two chemicals might be the same constitutional isomer, but upon deeper analysis be stereoisomers of each other. Two molecules that are the same stereoisomer as each other might be in different conformational forms or be different Isotopologue, isotopologues. The depth of analy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar Acid
In organic chemistry, a sugar acid or acidic sugar is a monosaccharide with a carboxyl group at one end or both ends of its Polymer backbone, chain. Main classes of sugar acids include: * Aldonic acids, in which the aldehyde group () located at the initial end (Monosaccharide#Linear-chain monosaccharides, position 1) of an aldose is oxidized. * Ulosonic acids, in which the hydroxymethyl group () at the initial end of a 2-ketose is oxidized creating an α-ketoacid. * Uronic acids, in which the group at the terminal end of an aldose or ketose is oxidized. * Aldaric acids, in which both ends ( and ) of an aldose are oxidized. Examples Examples of sugar acids include: * Aldonic acids ** Glyceric acid (3C) ** Xylonic acid (5C) ** Gluconic acid (6C) ** Ascorbic acid (6C, unsaturated lactone) * Ulosonic acids ** Neuraminic acid (5-amino-3,5-dideoxy-D-glyceraldehyde, ''glycero''-D-galactose, ''galacto''-non-2-ulosonic acid) ** Ketodeoxyoctulosonic acid (KDO or 3-deoxy-D-mannose, ''mann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactone
Lactones are cyclic carboxylic esters. They are derived from the corresponding hydroxycarboxylic acids by esterification. They can be saturated or unsaturated. Lactones are formed by lactonization, the intramolecular esterification of the corresponding hydroxycarboxylic acids. Nomenclature Greek alphabet#Letters, Greek prefixes in alphabetical order indicate ring size. Lactones are usually named according to the precursor acid molecule (''aceto'' = 2 carbon atoms, ''propio'' = 3, ''butyro'' = 4, ''valero'' = 5, ''capro'' = 6, etc.), with a ''-lactone'' suffix and a Greek letter prefix that specifies the number of carbon atoms in the heterocycle — that is, the distance between the relevant -OH and the -COOH groups along said backbone. The first carbon atom after the carbon in the -COOH group on the parent compound is labelled α, the second will be labeled β, and so forth. Therefore, the prefixes also indicate the size of the lactone ring: α-lactone = 3-membered ring, β-lac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydration
In physiology, dehydration is a lack of total body water that disrupts metabolic processes. It occurs when free water loss exceeds intake, often resulting from excessive sweating, health conditions, or inadequate consumption of water. Mild dehydration can also be caused by immersion diuresis, which may increase risk of decompression sickness in divers. Most people can tolerate a 3-4% decrease in total body water without difficulty or adverse health effects. A 5-8% decrease can cause fatigue and dizziness. Loss of over 10% of total body water can cause physical and mental deterioration, accompanied by severe thirst. Death occurs with a 15 and 25% loss of body water.Ashcroft F, Life Without Water in Life at the Extremes. Berkeley and Los Angeles, 2000, 134-138. Mild dehydration usually resolves with oral rehydration, but severe cases may need intravenous fluids. Dehydration can cause hypernatremia (high levels of sodium ions in the blood). This is distinct from hypovolemia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomonas Fragi
''Pseudomonas fragi'' is a psychrophilic, Gram-negative bacterium that is responsible for dairy spoilage. Unlike many other members of the genus ''Pseudomonas'', ''P. fragi'' does not produce siderophores. Optimal temperature for growth is 30 °C, however it can grow between 0 and 35 °C. Based on 16S rRNA Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal ... analysis, ''P. fragi'' has been placed in the '' P. chlororaphis'' group. References External linksType strain of ''Pseudomonas fragi'' at Bac''Dive'' - the Bacterial Diversity Metadatabase Pseudomonadales Bacteria described in 1902 {{Pseudomonadales-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escherichia Coli
''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly found in the lower intestine of warm-blooded organisms. Most ''E. coli'' strains are part of the normal microbiota of the gut, where they constitute about 0.1%, along with other facultative anaerobes. These bacteria are mostly harmless or even beneficial to humans. For example, some strains of ''E. coli'' benefit their hosts by producing vitamin K2 or by preventing the colonization of the intestine by harmful pathogenic bacteria. These mutually beneficial relationships between ''E. coli'' and humans are a type of mutualistic biological relationship—where both the humans and the ''E. coli'' are benefitting each other. ''E. coli'' is expelled into the environment within fecal matter. The bacterium grows massi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2,4-Butanetriol
1,2,4-Butanetriol is an organic compound with the formula . It is an colorless, odorless, hygroscopic, oily liquid. Containing three alcohol groups, it is classified as a polyol, similar to glycerol and erythritol. It is chiral. Uses 1,2,4-Butanetriol is used in the manufacture of butanetriol trinitrate (BTTN), an important component of US military rocket motor solid fuel. As of 2014, it was commercially produced by a single Chinese company. 1,2,4-Butanetriol is also used as a precursor for two cholesterol-lowering drugs, Crestor and Zetia, which are derived from D-3,4-dihydroxybutanoic acid, by using 3-hydroxy-gamma-butyrolactone as a chiral synthon It is used as one of the monomers for manufacture of some polyesters and as a solvent. Preparation 1,2,4-Butanetriol can be prepared synthetically by several methods, such as hydroformylation of glycidol and subsequent reduction of the product. It can also be prepared by reduction of malic acid esters with sodium borohydride. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar Acids
In organic chemistry, a sugar acid or acidic sugar is a monosaccharide with a carboxyl group at one end or both ends of its chain. Main classes of sugar acids include: * Aldonic acids, in which the aldehyde group () located at the initial end ( position 1) of an aldose is oxidized. * Ulosonic acids, in which the hydroxymethyl group () at the initial end of a 2-ketose is oxidized creating an α-ketoacid. * Uronic acids, in which the group at the terminal end of an aldose or ketose is oxidized. * Aldaric acids, in which both ends ( and ) of an aldose are oxidized. Examples Examples of sugar acids include: * Aldonic acids ** Glyceric acid (3C) ** Xylonic acid (5C) ** Gluconic acid (6C) ** Ascorbic acid (6C, unsaturated lactone) * Ulosonic acids ** Neuraminic acid (5-amino-3,5-dideoxy-D- ''glycero''-D- ''galacto''-non-2-ulosonic acid) ** Ketodeoxyoctulosonic acid (KDO or 3-deoxy-D- ''manno''-oct-2-ulosonic acid) * Uronic acids ** Glucuronic acid (6C) ** Galacturonic acid (6C) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
