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Theobromine
Theobromine, also known as xantheose, is the principal alkaloid of ''Theobroma cacao'' (cacao plant). Theobromine is slightly water-soluble (330 mg/L) with a bitter taste. In industry, theobromine is used as an additive and precursor to some cosmetics. It is found in chocolate, as well as in a number of other foods, including the leaves of the tea plant, and the kola nut. It is a white or colourless solid, but commercial samples can appear yellowish. Structure Theobromine is a flat molecule, a derivative of purine. It is also classified as a dimethyl xanthine. Related compounds include theophylline, caffeine, paraxanthine, and 7-methylxanthine, each of which differ in the number or placement of the methyl groups. History Theobromine was first discovered in 1841 in cacao beans by Russian chemist Aleksandr Voskresensky. Synthesis of theobromine from xanthine was first reported in 1882 by Hermann Emil Fischer. Etymology ''Theobromine'' is derived from ''Theobroma'', the na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caffeine
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. It is mainly used recreationally as a cognitive enhancer, increasing alertness and attentional performance. Caffeine acts by blocking binding of adenosine to the adenosine A1 receptor, which enhances release of the neurotransmitter acetylcholine. Caffeine has a three-dimensional structure similar to that of adenosine, which allows it to bind and block its receptors. Caffeine also increases cyclic AMP levels through nonselective inhibition of phosphodiesterase. Caffeine is a bitter, white crystalline purine, a methylxanthine alkaloid, and is chemically related to the adenine and guanine bases of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It is found in the seeds, fruits, nuts, or leaves of a number of plants native to Africa, East Asia and South America, and helps to protect them against herbivores and from competition by preventing the germination of nearby seeds, as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chocolate
Chocolate is a food made from roasted and ground cacao seed kernels that is available as a liquid, solid, or paste, either on its own or as a flavoring agent in other foods. Cacao has been consumed in some form since at least the Olmec civilization (19th-11th century BCE), and the majority of Mesoamerican people ─ including the Maya and Aztecs ─ made chocolate beverages. The seeds of the cacao tree have an intense bitter taste and must be fermented to develop the flavor. After fermentation, the seeds are dried, cleaned, and roasted. The shell is removed to produce cocoa nibs, which are then ground to cocoa mass, unadulterated chocolate in rough form. Once the cocoa mass is liquefied by heating, it is called chocolate liquor. The liquor may also be cooled and processed into its two components: cocoa solids and cocoa butter. Baking chocolate, also called bitter chocolate, contains cocoa solids and cocoa butter in varying proportions, without any added sugar. Powder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chocolate02
Chocolate is a food made from roasted and ground cacao seed kernels that is available as a liquid, solid, or paste, either on its own or as a flavoring agent in other foods. Cacao has been consumed in some form since at least the Olmec civilization (19th-11th century BCE), and the majority of Mesoamerican people ─ including the Maya and Aztecs ─ made chocolate beverages. The seeds of the cacao tree have an intense bitter taste and must be fermented to develop the flavor. After fermentation, the seeds are dried, cleaned, and roasted. The shell is removed to produce cocoa nibs, which are then ground to cocoa mass, unadulterated chocolate in rough form. Once the cocoa mass is liquefied by heating, it is called chocolate liquor. The liquor may also be cooled and processed into its two components: cocoa solids and cocoa butter. Baking chocolate, also called bitter chocolate, contains cocoa solids and cocoa butter in varying proportions, without any added sugar. Powdered bak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthine
Xanthine ( or ; archaically xanthic acid; systematic name 3,7-dihydropurine-2,6-dione) is a purine base (genetics), base found in most human body tissues and fluids, as well as in other organisms. Several stimulants are derived from xanthine, including caffeine, theophylline, and theobromine. Xanthine is a product on the pathway of purine degradation. * It is created from guanine by guanine deaminase. * It is created from hypoxanthine by xanthine oxidoreductase. * It is also created from xanthosine by purine nucleoside phosphorylase. Xanthine is subsequently converted to uric acid by the action of the xanthine oxidase enzyme. Use and manufacturing Xanthine is used as a drug precursor (chemistry), precursor for human and animal medications, and is manufactured as a pesticide ingredient. Clinical significance Derivatives of xanthine (known collectively as xanthines) are a group of alkaloids commonly used for their effects as mild stimulants and as bronchodilators, notably in the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cocoa Bean
The cocoa bean (technically cocoa seed) or simply cocoa (), also called the cacao bean (technically cacao seed) or cacao (), is the dried and fully fermented seed of ''Theobroma cacao'', from which cocoa solids (a mixture of nonfat substances) and cocoa butter (the fat) can be extracted. Cocoa beans are the basis of chocolate, and Mesoamerican foods including tejate, an indigenous Mexican drink that also includes maize, and pinolillo, a similar Nicaraguan drink made from a cornmeal & cocoa powder. Etymology The word ''cocoa'' comes from the Spanish word , which is derived from the Nahuatl word . The Nahuatl word, in turn, ultimately derives from the reconstructed Proto-Mixe–Zoquean word ''kakawa''. Used on its own, the term ''cocoa'' may also mean: * Hot cocoa, the drink more known as ''hot chocolate'' Terms derived from ''cocoa'' include: * Cocoa paste, ground cocoa beans: the mass is melted and separated into: ** Cocoa butter, a pale, yellow, edible fat ** Cocoa s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraxanthine
Paraxanthine, or 1,7-dimethylxanthine, is a dimethyl derivative of xanthine, structurally related to caffeine. Production and metabolism Paraxanthine is not known to be produced by plants but is observed in nature as a metabolite of caffeine in animals and some species of bacteria. After intake, roughly 84% of caffeine is demethylated at the 3-position to yield paraxanthine, making it the primary metabolite of caffeine in humans. Paraxanthine is also a major metabolite of caffeine in humans and other animals, such as mice. Shortly after ingestion, caffeine is metabolized into paraxanthine by hepatic cytochrome P450, which removes a methyl group from the N3 position of caffeine. After formation, paraxanthine can be broken down to 7-methylxanthine by demethylation of the N1 position, which is subsequently demethylated into xanthine or oxidized by CYP2A6 and CYP1A2 into 1,7-dimethyluric acid. In another pathway, paraxanthine is broken down into 5-acetylamino-6-formylamino-3-methylu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aleksandr Voskresensky
Aleksandr Abramovich Voskresensky (Russian: Александр Абрамович Воскресенский; 25 November 1808 – 21 January 1880) was a Russian chemist who served as rector of Saint Petersburg Imperial University in 1861–1863 and 1865–1867. Dmitri Mendeleev regarded him as a "grandfather of Russian chemistry". One of his major scientific achievements is the discovery of theobromine, the major alkaloid of cacao beans. Biography Voskresensky was born to a family of a poor priest, who died in 1814. He had one sister and one brother. From early ages he showed talents for sciences, and, after graduating from the St. Petersburg Institute of Pedagogy in 1836, was sent to Germany to continue his education. There he attended courses of Eilhard Mitscherlich, Heinrich Rose and Justus von Liebig, who considered Voskresensky one his most talented students. With Liebig he started his own chemical research. After returning to Russia in 1838 he was appointed as assistant t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermann Emil Fischer
Hermann Emil Louis Fischer (; 9 October 1852 – 15 July 1919) was a German chemist and 1902 recipient of the Nobel Prize in Chemistry. He discovered the Fischer esterification. He also developed the Fischer projection, a symbolic way of drawing asymmetric carbon atoms. He also hypothesized lock and key mechanism of enzyme action. He never used his first given name, and was known throughout his life simply as Emil Fischer. Early years and career Fischer was born in Euskirchen, near Cologne, the son of Laurenz Fischer, a businessman, and his wife Julie Poensgen. After graduating he wished to study natural sciences, but his father compelled him to work in the family business until determining that his son was unsuitable. Fischer then attended the University of Bonn in 1871, but switched to the University of Strasbourg in 1872. He earned his doctorate in 1874 under Adolf von Baeyer with his study of phthaleins, and was appointed to a position at the university. After eight ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theobroma
''Theobroma'' is a genus of flowering plants in the mallow family, Malvaceae, that is sometimes classified as a member of Sterculiaceae. It contains roughly 20 species of small understory trees native to the tropical forests of Central and South America. ''Theobroma cacao'', the best known species of the genus, is used for making chocolate. Cupuaçu (''Theobroma grandiflorum'') and Mocambo (''Theobroma bicolor'') are also of some economic importance. Taxonomy The generic name is derived from the Greek words ''theos'' meaning "god" and ''broma'' meaning "food" translating to "food of the gods". Selected species *''Theobroma angustifolium'' DC. *''Theobroma bicolor'' Humb. & Bonpl. – mocambo *''Theobroma cacao'' L. – cacao *''Theobroma canumanense'' Pires & Froes ex Cuatrec. *''Theobroma grandiflorum'' (Willd. ex Spreng.) K.Schum. – cupuaçu *''Theobroma mammosum'' Cuatrec. & Léon *''Theobroma microcarpum'' Mart. *''Theobroma obovatum'' Klotzsch ex B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Houghton Mifflin Company
Houghton Mifflin Harcourt (; HMH) is an American publisher of textbooks, instructional technology materials, assessments, reference works, and fiction and non-fiction for both young readers and adults. The company is based in the Boston Financial District. It was formerly known as Houghton Mifflin Company, but it changed its name following the 2007 acquisition of Harcourt Publishing. Prior to March 2010, it was a subsidiary of Education Media and Publishing Group Limited, an Irish-owned holding company registered in the Cayman Islands and formerly known as Riverdeep. History Ticknor and Allen, 1832 In 1832, William Ticknor and John Allen purchased a bookselling business in Boston and began to involve themselves in publishing; James T. Fields joined as a partner in 1843. Fields and Ticknor gradually gathered an impressive list of writers, including Ralph Waldo Emerson, Nathaniel Hawthorne, and Henry David Thoreau. The duo formed a close relationship with Riverside Press, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases, and Lewis bases. All definitions agree that bases are substances that react with acids, as originally proposed by G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form Hydroxide ions OH−. These ions can react with hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction An acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their applica .... A base was therefore a metal hydroxide such as Sodium hydroxide, NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
