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Ortho-Vanillin
''ortho''-Vanillin (2-hydroxy-3-methoxybenzaldehyde) is an organic solid present in the extracts and essential oils of many plants. Its functional groups include aldehyde, ether and phenol. ''ortho''-Vanillin, a compound of the formula C8H8O3, is distinctly different from its more prevalent isomer, ''meta''-vanillin. The "'' ortho''-" prefix refers to the position of the compound’s hydroxyl moiety, which is found in the ''para''-position in vanillin. ''ortho''-Vanillin is a fibrous, light-yellow, crystalline solid. Present in a variety of food products, it is not specifically sought after, and is therefore a less-commonly produced and encountered food additive. History ''ortho''-Vanillin was first isolated, in 1876, by renowned German chemist Ferdinand Tiemann. By 1910, methods for its purification had been developed by Francis Noelting, who similarly demonstrated its versatility as a general synthetic precursor for a diverse array of compounds, such as the coumarins. By ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanillin
Vanillin is an organic compound with the molecular formula . It is a phenolic aldehyde. Its functional groups include aldehyde, hydroxyl, and ether. It is the primary component of the extract of the vanilla bean. Synthetic vanillin is now used more often than natural vanilla extract as a flavoring in foods, beverages, and pharmaceuticals. Vanillin and ethylvanillin are used by the food industry; ethylvanillin is more expensive, but has a stronger note. It differs from vanillin by having an ethoxy group (−O−CH2CH3) instead of a methoxy group (−O−CH3). Natural vanilla extract is a mixture of several hundred different compounds in addition to vanillin. Artificial vanilla flavoring is often a solution of pure vanillin, usually of synthetic origin. Because of the scarcity and expense of natural vanilla extract, synthetic preparation of its predominant component has long been of interest. The first commercial synthesis of vanillin began with the more readily available na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanillin
Vanillin is an organic compound with the molecular formula . It is a phenolic aldehyde. Its functional groups include aldehyde, hydroxyl, and ether. It is the primary component of the extract of the vanilla bean. Synthetic vanillin is now used more often than natural vanilla extract as a flavoring in foods, beverages, and pharmaceuticals. Vanillin and ethylvanillin are used by the food industry; ethylvanillin is more expensive, but has a stronger note. It differs from vanillin by having an ethoxy group (−O−CH2CH3) instead of a methoxy group (−O−CH3). Natural vanilla extract is a mixture of several hundred different compounds in addition to vanillin. Artificial vanilla flavoring is often a solution of pure vanillin, usually of synthetic origin. Because of the scarcity and expense of natural vanilla extract, synthetic preparation of its predominant component has long been of interest. The first commercial synthesis of vanillin began with the more readily available na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugenol
Eugenol is an allyl chain-substituted guaiacol, a member of the allylbenzene class of chemical compounds. It is a colorless to pale yellow, aromatic oily liquid extracted from certain essential oils especially from clove, nutmeg, cinnamon, basil and bay leaf. It is present in concentrations of 80–90% in clove bud oil and at 82–88% in clove leaf oil. Eugenol has a pleasant, spicy, clove-like scent. The name is derived from ''Eugenia caryophyllata'', the former Linnean nomenclature term for cloves. The currently accepted name is ''Syzygium aromaticum''. Biosynthesis The biosynthesis of eugenol begins with the amino acid tyrosine. L-tyrosine is converted to ''p''-coumaric acid by the enzyme tyrosine ammonia lyase (TAL). From here, ''p''-coumaric acid is converted to caffeic acid by ''p''-coumarate 3-hydroxylase using oxygen and NADPH. ''S''-Adenosyl methionine (SAM) is then used to methylate caffeic acid, forming ferulic acid, which is in turn converted to feruloyl- CoA by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferdinand Tiemann
Johann Karl Wilhelm Ferdinand Tiemann (June 10, 1848 – November 14, 1899) was a German chemist and together with Karl Reimer discoverer of the Reimer-Tiemann reaction. Beginning in 1866, Tiemann studied pharmacy at the TU Braunschweig where he graduated in 1869. His professor in Brunswick wrote a letter of recommendation to August Wilhelm von Hofmann at the University of Berlin where Tiemann started as assistant of von Hofmann in 1869. In 1874 Wilhelm Haarmann and Tiemann started a company, after they discovered the synthesis of vanillin from coniferyl alcohol. The vanillin plant Holzminden was not very successful before Karl Reimer discovered the Reimer-Tiemann reaction which opened an alternative synthesis route to vanillin. In 1882 Tiemann became a professor at the University of Berlin. He was involved in the first synthesis of Jonon a compound of the sweet violet (''Viola odorata ''Viola odorata'' is a species of flowering plant in the genus ''Viola'', native to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibacterial
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against microbes, but in the usual medical usage, antibiotics (such as penicillin) are those produced naturally (by one microorganism fighting another), whereas non-antibiotic antibacterials (such as sulfonamides and antiseptics) ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antifungal
An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as cryptococcal meningitis, and others. Such drugs are usually yes obtained by a doctor's prescription, but a few are available over the counter (OTC). Types of antifungal There are two types of antifungals: local and systemic. Local antifungals are usually administered topically or vaginally, depending on the condition being treated. Systemic antifungals are administered orally or intravenously. Of the clinically employed azole antifungals, only a handful are used systemically. These include ketoconazole, itraconazole, fluconazole, fosfluconazole, voriconazole, posaconazole, and isavuconazole. Examples of non-azole systemic antifungals include griseofulvin and terbinafine. Classes Polyenes A polyene is a molecule with multiple conjugated do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escherichia Coli
''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), 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 harmless, but some serotypes ( EPEC, ETEC etc.) can cause serious food poisoning in their hosts, and are occasionally responsible for food contamination incidents that prompt product recalls. Most strains do not cause disease in humans and are part of the normal microbiota of the gut; such strains are harmless or even beneficial to humans (although these strains tend to be less studied than the pathogenic ones). For example, some strains of ''E. coli'' benefit their hosts by producing vitamin K2 or by preventing the colonization of the intestine by pathogenic bacteria. These mutually beneficial relationships between ''E. col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comutagen
A comutagen is a substance that is not a mutagen by itself, but in the presence of a mutagen, enhances mutagenic activity. There are at least two manners by which this may occur; the comutagen may strengthen the mutagenic activity of mutagenic chemicals, or it can create a mutagenic response from nonmutagens. Chemicals such as harmane and norharmane β-Carboline (9''H''- pyrido ,4-''b'' ndole) represents the basic chemical structure for more than one hundred alkaloids and synthetic compounds. The effects of these substances depend on their respective substituent. Natural β-carbolines prima ... (present in tobacco tar) have been identified as comutagens. References {{Biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutagen
In genetics, a mutagen is a physical or chemical agent that permanently changes nucleic acid, genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer in animals, such mutagens can therefore be carcinogens, although not all necessarily are. All mutagens have characteristic mutational signatures with some chemicals becoming mutagenic through cellular processes. The process of DNA becoming modified is called mutagenesis. Not all mutations are caused by mutagens: so-called "spontaneous mutations" occur due to spontaneous hydrolysis, DNA error, errors in DNA replication, repair and Genetic recombination, recombination. Discovery The first mutagens to be identified were carcinogens, substances that were shown to be linked to cancer. Tumors were described more than 2,000 years before the discovery of chromosomes and DNA; in 500 B.C., the Greece, Greek physician Hippocrates named tu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrosinase
Tyrosinase is an oxidase that is the rate-limiting enzyme for controlling the production of melanin. The enzyme is mainly involved in two distinct reactions of melanin synthesis otherwise known as the Raper Mason pathway. Firstly, the hydroxylation of a monophenol and secondly, the conversion of an o-diphenol to the corresponding o-quinone. o-Quinone undergoes several reactions to eventually form melanin. Tyrosinase is a copper-containing enzyme present in plant and animal tissues that catalyzes the production of melanin and other pigments from tyrosine by oxidation. It is found inside melanosomes which are synthesized in the skin melanocytes. In humans, the tyrosinase enzyme is encoded by the ''TYR'' gene. Catalyzed reaction Tyrosinase carries out the oxidation of phenols such as tyrosine and dopamine using dioxygen (O2). In the presence of catechol, benzoquinone is formed (see reaction below). Hydrogens removed from catechol combine with oxygen to form water. The substrate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme Inhibitor
An enzyme inhibitor is a molecule that binds to an enzyme and blocks its activity. Enzymes are proteins that speed up chemical reactions necessary for life, in which substrate molecules are converted into products. An enzyme facilitates a specific chemical reaction by binding the substrate to its active site, a specialized area on the enzyme that accelerates the most difficult step of the reaction. An enzyme inhibitor stops ("inhibits") this process, either by binding to the enzyme's active site (thus preventing the substrate itself from binding) or by binding to another site on the enzyme such that the enzyme's catalysis of the reaction is blocked. Enzyme inhibitors may bind reversibly or irreversibly. Irreversible inhibitors form a chemical bond with the enzyme such that the enzyme is inhibited until the chemical bond is broken. By contrast, reversible inhibitors bind non-covalently and may spontaneously leave the enzyme, allowing the enzyme to resume its function. Reve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hide (skin)
A hide or skin is an animal skin treated for human use. The word "hide" is related to the German word "Haut" which means skin. The industry defines hides as "skins" of large animals ''e.g''. cow, buffalo; while skins refer to "skins" of smaller animals: goat, sheep, deer, pig, fish, alligator, snake, etc. Common commercial hides include leather from cattle and other livestock animals, buckskin (leather), buckskin, alligator, alligator skin and snake skin. All are used for shoes, clothes, leather bags, belts, or other fashion Fashion accessory, accessories. Leather is also used in cars, upholstery, interior decorating, horse tack and horse harness, harnesses. Skins are sometimes still gathered from hunting and processed at a domestic or artisanal level but most leather making is now industrialization, industrialized and large-scale. Various tannins are used for this purpose. Hides are also used as processed chews for dogs or other pets. The term "skin" is sometimes expanded to inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
