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Phenolic Lipids
Phenolic lipids are a class of natural products composed of long aliphatic chains and phenolic rings. Phenolic lipids occur in plants, fungi and bacteria. Types * Alkylcatechols * Alkylphenols (nonylphenol, cardanol) * Alkylresorcinols * Anacardic acids Biological activity Due to their strong amphiphilic character, the phenolic lipids can incorporate into erythrocytes and liposomal membranes. The ability of these compounds to inhibit bacterial, fungal, protozoan and parasite growth seems to depend on their interaction with proteins and/or on their membrane-disturbing properties. Biological role The phenolic lipid synthesis by type III polyketide synthases is essential for cyst formation in ''Azotobacter vinelandii''. See also * Lipid Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bilobol
Bilobol is an alkylresorcinol, a type of natural phenol, phenolic lipids composed of long aliphatic chains and phenolic rings. Chemically, it is similar in structure to urushiol, the irritant found in poison ivy; it is a strong skin irritant itself. Natural occurrences Bilobol can be found in ''Ginkgo biloba'' fruits. References Alkylresorcinols {{phenol-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aliphatic Compound
In organic chemistry, hydrocarbons ( compounds composed solely of carbon and hydrogen) are divided into two classes: aromatic compounds and aliphatic compounds (; G. ''aleiphar'', fat, oil). Aliphatic compounds can be saturated, like hexane, or unsaturated, like hexene and hexyne. Open-chain compounds, whether straight or branched, and which contain no rings of any type, are always aliphatic. Cyclic compounds can be aliphatic if they are not aromatic. Structure Aliphatic compounds can be saturated, joined by single bonds (alkanes), or unsaturated, with double bonds (alkenes) or triple bonds ( alkynes). If other elements (heteroatoms) are bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine, it is no longer a hydrocarbon, and therefore no longer an aliphatic compound. The least complex aliphatic compound is methane (CH4). Properties Most aliphatic compounds are flammable, allowing the use of hydrocarbons as fuel, such as methane in Bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Phenol
In biochemistry, naturally occurring phenols are natural products containing at least one phenol functional group. Phenolic compounds are produced by plants and microorganisms. Organisms sometimes synthesize phenolic compounds in response to ecological pressures such as pathogen and insect attack, UV radiation and wounding. As they are present in food consumed in human diets and in plants used in traditional medicine of several cultures, their role in human health and disease is a subject of research. Some phenols are germicidal and are used in formulating disinfectants. Classification Various classification schemes can be applied. A commonly used scheme is based on the number of carbons and was devised by Jeffrey Harborne and Simmonds in 1964 and published in 1980: C6-C7-C6 Diarylheptanoids are not included in this Harborne classification. They can also be classified on the basis of their number of phenol groups. They can therefore be called ''simple phenols'' or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkylphenol
Alkylphenols are a family of organic compounds obtained by the alkylation of phenols. The term is usually reserved for commercially important propylphenol, butylphenol, amylphenol, heptylphenol, octylphenol, nonylphenol, dodecylphenol and related "long chain alkylphenols" (LCAPs). Methylphenols and ethylphenols are also alkylphenols, but they are more commonly referred to by their specific names, cresols and xylenols. Production The long-chain alkylphenols are prepared by alkylation of phenol with alkenes: :C6H5OH + RR'C=CHR" → RR'CH−CHR"−C6H4OH In this way, about 500M kg/y are produced. Environmental controversy over nonylphenols Alkylphenols are xenoestrogens. Long chain Alkylphenols have the most potent estrogenic activity. The European Union has implemented sales and use restrictions on certain applications in which nonylphenols are used because of their alleged "toxicity, persistence, and the liability to bioaccumulate" but the United States EPA has taken a slo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardanol
Cardanol is a phenolic lipid obtained from anacardic acid, the main component of cashew nutshell liquid (CNSL), a byproduct of cashew nut processing. Cardanol finds use in the chemical industry in resins, coatings, frictional materials, and surfactants used as pigment dispersants for water-based inks. It is used to make phenalkamines, which are used as curing agents for the durable epoxy coatings used on concrete floors. The name of the substance is derived by contraction from the genus ''Anacardium'', which includes the cashew tree, ''Anacardium occidentale''. The name of the genus itself is based on the Greek word for ''heart''. Friction particles are made by polymerizing the unsaturated side chain of cardanol, followed by cross-polymerization with formaldehyde to yield a cardanol-formaldehyde resin by a process analogous to the formation of phenol-formaldehyde resins such as Bakelite. Cardanol-phenol resins were developed in the 1920s by Mortimer T. Harvey, then a student at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkylresorcinol
Alkylresorcinols, also known as resorcinolic lipids, are phenolic lipids composed of long aliphatic chains and resorcinol-type phenolic rings. Natural sources of alkylresorcinols Alkylresorcinols are relatively rare in nature, with the main known sources being wheat, rye, barley, triticale (cereal grasses), quinoa, the fruit of ''Ginkgo biloba'' Bilobol, a mollusc and some species of bacteria. DB-2073 is an antibiotic isolated from the broth culture of ''Pseudomonas'' sp. They are also the main constituents of the outer shell of the cyst of ''Azotobacter''. Occurrence in cereals Alkylresorcinols are present in high amounts in the bran layer (e.g. pericarp, testa and aleurone layers) of wheat and rye (0.1-0.3 % of dry weight). 5-Alkylresorcinols can also be found in rice, though not in the edible parts of the rice plant. They are only present in very low amounts in the endosperm (the part of cereal grain that is used to make white flour), which means that alkylresorcinols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anacardic Acid
Anacardic acids are phenolic lipids, chemical compounds found in the shell of the cashew nut (''Anacardium occidentale''). An acid form of urushiol, they also cause an allergic skin rash on contact, known as urushiol-induced contact dermatitis. Anacardic acid is a yellow liquid. It is partially miscible with ethanol and ether, but nearly immiscible with water. Chemically, anacardic acid is a mixture of several closely related organic compounds. Each consists of a salicylic acid substituted with an alkyl chain that has 15 or 17 carbon atoms. The alkyl group may be saturated or unsaturated; anacardic acid is a mixture of saturated and unsaturated molecules. The exact mixture depends on the species of the plant. The 15-carbon unsaturated side chain compound found in the cashew plant is lethal to Gram-positive bacteria. Folk use for tooth abscesses, it is also active against acne, some insects, tuberculosis, and MRSA. It is primarily found in foods such as cashew nuts, cashew apples ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type III Polyketide Synthase
Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * Type (Unix), a command in POSIX shells that gives information about commands. * Type safety, the extent to which a programming language discourages or prevents type errors. * Type system, defines a programming language's response to data types. Mathematics * Type (model theory) * Type theory, basis for the study of type systems * Arity or type, the number of operands a function takes * Type, any proposition or set in the intuitionistic type theory * Type, of an entire function ** Exponential type Biology * Type (biology), which fixes a scientific name to a taxon * Dog type, categorization by use or function of domestic dogs Lettering * Type is a design concept for lettering used in typography which helped bring about modern textual print ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azotobacter Vinelandii
''Azotobacter vinelandii'' is Gram-negative diazotroph that can fix nitrogen while grown aerobically. These bacteria are easily cultured and grown. ''A. vinelandii'' is a free-living N2 fixer known to produce many phytohormones and vitamins in soils. It produces fluorescent pyoverdine pigments. Nitrogenase The nitrogenase holoenzyme of ''A. vinelandii'' has been characterised by X-ray crystallography in both ADP tetrafluoroaluminate-bound and Mg ATP-bound states. The enzyme possesses molybdenum iron- sulfido cluster cofactors (FeMoco) as active sites, each bearing two pseudocubic iron-sulfido structures. Applications It is a genetically tractable system that is used to study nitrogen fixation. Genetically engineered strains can produce significantly higher amounts of ammonia. Appropriate ammonia emissions can provide crops with the ammonia they need without excess amounts that can pollute lakes and oceans. Variable ploidy ''A. vinelandii'' can contain up to 80 chr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipid
Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing energy, signaling, and acting as structural components of cell membranes. Lipids have applications in the cosmetic and food industries, and in nanotechnology. Lipids may be broadly defined as hydrophobic or amphiphilic small molecules; the amphiphilic nature of some lipids allows them to form structures such as vesicles, multilamellar/unilamellar liposomes, or membranes in an aqueous environment. Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups. Using this approach, lipids may be divided into eight categories: fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from condensati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
