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Menthone
Menthone is a chemical compound of the monoterpene class of naturally occurring organic compounds found in a number of essential oils, one that presents with minty flavor. It is a specific pair of stereoisomers of the four possible such isomers for the chemical structure, 2-isopropyl-5-methylcyclohexanone. Of those, the stereoisoomer ''l''-menthone—formally, the (2''S'',5''R'')-''trans'' isomer of that structure, as shown at right—is the most abundant in nature. Menthone is structurally related to menthol, which has a secondary alcohol (>C-OH) in place of the carbon-oxygen double bond (carbonyl group) projecting from the cyclohexane ring. Menthone is obtained for commercial use after purifying essential oils pressed from Mentha species (peppermint and corn mint). It is used as a flavorant and in perfumes and cosmetics for its characteristic aromatic and minty aroma. Occurrence Menthone is a constituent of the essential oils of pennyroyal, peppermint, '' corn mint'', '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peppermint
Peppermint (''Mentha'' × ''piperita'') is a Hybrid (biology), hybrid species of Mentha, mint, a cross between Mentha aquatica, watermint and spearmint. Indigenous to Europe and the Middle East, the plant is now widely spread and cultivated in many regions of the world.Euro+Med Plantbase Project''Mentha'' × ''piperita''/ref> It is occasionally found in the wild with its parent species.Flora of NW Europe''Mentha'' × ''piperita'' Although the genus ''Mentha'' comprises more than 25 species, the one in most common use is peppermint. While Western peppermint is derived from ''Mentha × piperita'', Chinese peppermint, or ''bohe'', is derived from the fresh leaves of ''M. haplocalyx''. ''M. × piperita'' and ''M. haplocalyx'' are both recognized as plant sources of menthol and menthone, and are among the oldest herbs used for both culinary and medicinal products. Botany Peppermint was first identified in Hertfordshire, England, by a Dr. Eales, a discovery which John Ray publish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Menthol
Menthol is an organic compound, specifically a Monoterpene, monoterpenoid, that occurs naturally in the oils of several plants in the Mentha, mint family, such as Mentha arvensis, corn mint and peppermint. It is a white or clear waxy crystalline substance that is solid at room temperature and melts slightly above. The main form of menthol occurring in nature is (−)-menthol, which is assigned the (1''R'',2''S'',5''R'') Cahn–Ingold–Prelog priority rules, configuration. For many people, menthol produces a cooling sensation when inhaled, eaten, or applied to the skin, and mint plants have been used for centuries for topical pain relief and as a food flavoring. Menthol has local anesthetic and counterirritant qualities, and it is widely used to relieve minor throat irritation. Menthol has been demonstrated to cause a subjective nasal decongestant effect without any objective decongestant action, and administration of menthol via a nasal inhaler in humans has also been shown t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mentha Arvensis
''Mentha arvensis'', the corn mint, field mint, or wild mint, is a species of flowering plant in the mint family Lamiaceae. It has a circumboreal distribution, being native to the temperate regions of Europe and western and central Asia, east to the Himalaya and eastern Siberia, and North America. '' Mentha canadensis'', the related species, is also included in ''Mentha arvensis'' by some authors as two varieties, ''M. arvensis'' var. ''glabrata'' Fernald (North American plants such as American Wild Mint) and ''M. arvensis'' var. ''piperascens'' Malinv. ex L. H. Bailey (eastern Asian plants such as Japanese mint). It grows in moist places, especially along streams. Description Wild mint is a herbaceous perennial plant generally growing to and rarely up to tall. It has a creeping rootstock from which grow erect or semi-sprawling squarish stems. The leaves are in opposite pairs, simple, long and broad, hairy, and with a coarsely serrated margin. The flowers are pale purple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corn Mint
''Mentha arvensis'', the corn mint, field mint, or wild mint, is a species of flowering plant in the mint family Lamiaceae. It has a circumboreal distribution, being native to the temperate regions of Europe and western and central Asia, east to the Himalaya and eastern Siberia, and North America. ''Mentha canadensis'', the related species, is also included in ''Mentha arvensis'' by some authors as two varieties, ''M. arvensis'' var. ''glabrata'' Fernald (North American plants such as American Wild Mint) and ''M. arvensis'' var. ''piperascens'' Malinv. ex L. H. Bailey (eastern Asian plants such as Japanese mint). It grows in moist places, especially along streams. Description Wild mint is a herbaceous perennial plant generally growing to and rarely up to tall. It has a creeping rootstock from which grow erect or semi-sprawling squarish stems. The leaves are in opposite pairs, simple, long and broad, hairy, and with a coarsely serrated margin. The flowers are pale purple (o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mentha Pulegium
''Mentha pulegium'', commonly (European) pennyroyal, or pennyrile, also called mosquito plant and pudding grass, is a species of flowering plant in the Mentha, mint Family (biology), family, Lamiaceae, native to Europe, North Africa, and the Middle East. Crushed pennyroyal leaves emit a very strong fragrance similar to spearmint. Pennyroyal is a traditional folk remedy, emmenagogue, abortifacient, and culinary herb, but is toxic to the liver and has caused some deaths. European pennyroyal is related to an American species, ''Hedeoma pulegioides''. Though they differ in genera, they share similar chemical properties. Description An annual to perennial plant with creeping or erect branched stems to about 40 cm in height. The stems are square in cross-section and can vary from hairless on some plants to densely hairy on others, with a green to sometimes red or purplish colour. The leaves, which grow in Phyllotaxis, opposite pairs, are narrowly oval, 2–3 cm long x 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boiling Point
The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding environmental pressure. A liquid in a partial vacuum, i.e., under a lower pressure, has a lower boiling point than when that liquid is at atmospheric pressure. Because of this, water boils at 100°C (or with scientific precision: ) under standard pressure at sea level, but at at altitude. For a given pressure, different liquids will boiling, boil at different temperatures. The normal boiling point (also called the atmospheric boiling point or the atmospheric pressure boiling point) of a liquid is the special case in which the vapor pressure of the liquid equals the defined atmospheric pressure at sea level, one Atmosphere (unit), atmosphere. At that temperature, the vapor pressure of the liquid becomes sufficient to overcome atmospheric pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Density
Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' (or ''d'') can also be used: \rho = \frac, where ''ρ'' is the density, ''m'' is the mass, and ''V'' is the volume. In some cases (for instance, in the United States oil and gas industry), density is loosely defined as its weight per unit volume, although this is scientifically inaccurate this quantity is more specifically called specific weight. For a pure substance, the density is equal to its mass concentration. Different materials usually have different densities, and density may be relevant to buoyancy, purity and packaging. Osmium is the densest known element at standard conditions for temperature and pressure. To simplify comparisons of density across different systems of units, it is sometimes replaced by the dimensionless quantity "relative den ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melting Point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state of matter, state from solid to liquid. At the melting point the solid and liquid phase (matter), phase exist in Thermodynamic equilibrium, equilibrium. The melting point of a substance depends on pressure and is usually specified at a Standard temperature and pressure, standard pressure such as 1 Atmosphere (unit), atmosphere or 100 Pascal (unit), kPa. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of substances to Supercooling, supercool, the freezing point can easily appear to be below its actual value. When the "characteristic freezing point" of a substance is determined, in fact, the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice, that is, the #Melting point measurements, melting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circular Dichroism
Circular dichroism (CD) is dichroism involving circular polarization, circularly polarized light, i.e., the differential Absorption (electromagnetic radiation), absorption of left- and right-handed light. Left-hand circular (LHC) and right-hand circular (RHC) polarized light represent two possible spin angular momentum of light, spin angular momentum states for a photon, and so circular dichroism is also referred to as dichroism for spin angular momentum. This phenomenon was discovered by Jean-Baptiste Biot, Augustin Fresnel, and Aimé Cotton in the first half of the 19th century. Circular dichroism and optical rotation, circular birefringence are manifestations of optical activity. It is exhibited in the absorption (electromagnetic radiation), absorption bands of optical activity, optically active chirality (chemistry), chiral molecules. CD spectroscopy has a wide range of applications in many different fields. Most notably, Ultraviolet, far-UV CD is used to investigate the second ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Spectrometer
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a '' mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures. A mass spectrum is a type of plot of the ion signal as a function of the mass-to-charge ratio. These spectra are used to determine the elemental or isotopic signature of a sample, the masses of particles and of molecules, and to elucidate the chemical identity or structure of molecules and other chemical compounds. In a typical MS procedure, a sample, which may be solid, liquid, or gaseous, is ionized, for example by bombarding it with a beam of electrons. This may cause some of the sample's molecules to break up into positively charged fragments or simply become positively charged without fragmenting. These ions (fragments) are then separated accor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reviews
''Chemical Reviews'' is peer-reviewed scientific journal published twice per month by the American Chemical Society. It publishes review articles on all aspects of chemistry. It was established in 1924 by William Albert Noyes (University of Illinois). The editor-in-chief is Sharon Hammes-Schiffer. Abstracting and indexing The journal is abstracted and indexed in Chemical Abstracts Service, CAB International, EBSCOhost, ProQuest, PubMed, Scopus, and the Science Citation Index. According to the ''Journal Citation Reports'', the journal has a 2023 impact factor of 51.4. Journal ranking summary Based on the latest announced rankings, ''Chemical Reviews'' is positioned among the top journals in the field of chemistry across multiple citation databases. The following table summarizes its performance across Scopus and Web of Science. Journal ranking summary (2023)JRank: Chemical Reviewshttps://jrank.net/journals/chem-rev/metrics/ref> See also * Accounts of Chemical Research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asymmetric Carbon
In stereochemistry, an asymmetric carbon is a carbon atom that is bonded to four different types of atoms or groups of atoms. The four atoms and/or groups attached to the carbon atom can be arranged in space in two different ways that are mirror images of each other, and which lead to so-called ''left-handed'' and ''right-handed'' versions (stereoisomers) of the same molecule. Molecules that cannot be superimposed on their own mirror image are said to be chiral; as the asymmetric carbon is the center of this chirality, it is also known as a chiral carbon. As an example, malic acid () has 4 carbon atoms but just one of them is asymmetric. The asymmetric carbon atom, bolded in the formula, is the one attached to two carbon atoms, an oxygen atom, and a hydrogen atom. One may initially be inclined to think this atom is not asymmetric because it is attached to two carbon atoms, but because those two carbon atoms are not attached to exactly the same things, there are two different '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
