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α-Parinaric Acid
α-Parinaric acid is a conjugated fatty acid, conjugated polyunsaturated fatty acid. Discovered by Tsujimoto and Koyanagi in 1933, it contains 18 carbon atoms and 4 conjugated system, conjugated double bonds. The repeating single bond-double bond structure of α-parinaric acid distinguishes it structurally and chemically from the usual "methylene-interrupted" arrangement of polyunsaturated fatty acids that have double-bonds and single bonds separated by a methylene bridge, methylene unit (−CH2−). Because of the fluorescent properties conferred by the alternating double bonds, α-parinaric acid is commonly used as a molecular probe in the study of biological membranes, biomembranes. Natural sources α-Parinaric acid occurs naturally in the seeds of the Atuna racemosa racemosa, makita tree (''Parinari laurina''), a tree found in Fiji and other Pacific islands. Makita seeds contain about 46% α-parinaric acid, 34% α-eleostearic acid as major components, with lesser amounts of sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjugated Fatty Acid
Conjugated fatty acids is jargon for polyunsaturated fatty acids containing at least one pair of conjugated double bonds. An example of a conjugated fatty acid is the rumenic acid, found in the meat and milk of ruminants. Most unsaturated fatty acids that are doubly unsaturated do not feature conjugation, e.g., linoleic acid and linoelaidic acid. Some conjugated fatty acids may confer health benefits ranging from the prevention of hypertension to protection against certain forms of cancer, although more research is needed to confirm such effects. Clinical studies and animal models have shown that conjugated fatty acids confer physiological benefits such as the regulation of the synthesis and breakdown of lipids, reduction of inflammation, and antioxidant properties. Conjugated fatty acids include isomers of linoleic acid. Conjugated analogues linoleic acids are the most investigated conjugated fatty acids. The reason why the isomer of conjugated fatty acids are studied is because ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palmitic Acid
Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The Lipid Handbook, 3rd ed. Boca Raton: CRC Press, 2007. , Its chemical formula is CH3(CH2)14COOH, and its C:D (the total number of carbon atoms to the number of carbon-carbon double-bonds) is 16:0. It is a major component of the oil from the fruit of oil palms ( palm oil), making up to 44% of total fats. Meats, cheeses, butter, and other dairy products also contain palmitic acid, amounting to 50–60% of total fats. Palmitates are the salts and esters of palmitic acid. The palmitate anion is the observed form of palmitic acid at physiologic pH (7.4). Occurrence and production Palmitic acid was discovered by Edmond Frémy in 1840, in saponified palm oil. This remains the primary industrial route for its production, with the triglycerides (fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biophysical
Biophysics is an interdisciplinary science that applies approaches and methods traditionally used in physics to study biological phenomena. Biophysics covers all scales of biological organization, from molecular to organismic and populations. Biophysical research shares significant overlap with biochemistry, molecular biology, physical chemistry, physiology, nanotechnology, bioengineering, computational biology, biomechanics, developmental biology and systems biology. The term ''biophysics'' was originally introduced by Karl Pearson in 1892.Roland Glaser. Biophysics: An Introduction'. Springer; 23 April 2012. . The term ''biophysics'' is also regularly used in academia to indicate the study of the physical quantities (e.g. electric current, temperature, stress, entropy) in biological systems. Other biological sciences also perform research on the biophysical properties of living organisms including molecular biology, cell biology, chemical biology, and biochemistry. Overview Mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipid Bilayer
The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells. The cell membranes of almost all organisms and many viruses are made of a lipid bilayer, as are the nuclear membrane surrounding the cell nucleus, and membranes of the membrane-bound organelles in the cell. The lipid bilayer is the barrier that keeps ions, proteins and other molecules where they are needed and prevents them from diffusing into areas where they should not be. Lipid bilayers are ideally suited to this role, even though they are only a few nanometers in width, because they are impermeable to most water-soluble (hydrophilic) molecules. Bilayers are particularly impermeable to ions, which allows cells to regulate salt concentrations and pH by transporting ions across their membranes using proteins called ion pumps. Biological bilayers are usually composed of amphiphilic phosphol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Transition
In chemistry, thermodynamics, and other related fields, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic states of matter: solid, liquid, and gas, and in rare cases, plasma. A phase of a thermodynamic system and the states of matter have uniform physical properties. During a phase transition of a given medium, certain properties of the medium change as a result of the change of external conditions, such as temperature or pressure. This can be a discontinuous change; for example, a liquid may become gas upon heating to its boiling point, resulting in an abrupt change in volume. The identification of the external conditions at which a transformation occurs defines the phase transition point. Types of phase transition At the phase transition point for a substance, for instance the boiling point, the two phases involved - liquid and vapor, have identic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
α-linolenic Acid
''alpha''-Linolenic acid (ALA), also known as α-Linolenic acid (from Greek ''alpha'' meaning "first" and ''linon'' meaning flax), is an ''n''−3, or omega-3, essential fatty acid. ALA is found in many seeds and oils, including flaxseed, walnuts, chia, hemp, and many common vegetable oils. In terms of its structure, it is named ''all''-''cis''-9,12,15-octadecatrienoic acid. In physiological literature, it is listed by its lipid number, 18:3, and (''n''−3). It is a carboxylic acid with an 18-carbon chain and three ''cis'' double bonds. The first double bond is located at the third carbon from the methyl end of the fatty acid chain, known as the ''n'' end. Thus, α-linolenic acid is a polyunsaturated ''n''−3 (omega-3) fatty acid. It is an isomer of gamma-linolenic acid (GLA), an 18:3 (''n''−6) fatty acid (i.e., a polyunsaturated omega-6 fatty acid with three double bonds). Etymology The word ''linolenic'' is an irregular derivation from ''linoleic'', which itself is der ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one of the most important branches of organic chemistry. There are several main areas of research within the general area of organic synthesis: ''total synthesis'', ''semisynthesis'', and ''methodology''. Total synthesis A total synthesis is the complete chemical synthesis of complex organic molecules from simple, commercially available petrochemical or natural precursors. Total synthesis may be accomplished either via a linear or convergent approach. In a ''linear'' synthesis—often adequate for simple structures—several steps are performed one after another until the molecule is complete; the chemical compounds made in each step are called synthetic intermediates. Most often, each step in a synthesis refers to a separate rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desaturase
A fatty acid desaturase is an enzyme that removes two hydrogen atoms from a fatty acid, creating a carbon/carbon double bond. These desaturases are classified as: * Delta - indicating that the double bond is created at a fixed position from the carboxyl end of a fatty acid chain. For example, Δ9 desaturase creates a double bond between the ninth and tenth carbon atom from the carboxyl end. * Omega - indicating the double bond is created at a fixed position from the methyl end of a fatty acid chain. For instance, ω3 desaturase creates a double bond between the third and fourth carbon atom from the methyl end. In other words, it creates an omega-3 fatty acid. For example, Δ6 desaturation introduces a double bond between carbons 6 and 7 of Linoleic acid (LA C18H32O2; 18:2-n6) and α-Linolenic acid (ALA: C18H30O2; 18:3-n3), creating ''γ''-linolenic acid (GLA: C18H30O2,18:3-n6) and stearidonic acid (SDA: C18H28O2; 18:4-n3) respectively. In humans, Δ17-desaturase is able to tur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expressed Sequence Tag
In genetics, an expressed sequence tag (EST) is a short sub-sequence of a cDNA sequence. ESTs may be used to identify gene transcripts, and were instrumental in gene discovery and in gene-sequence determination. The identification of ESTs has proceeded rapidly, with approximately 74.2 million ESTs now available in public databases (e.g. GenBank 1 January 2013, all species). EST approaches have largely been superseded by whole genome and transcriptome sequencing and metagenome sequencing. An EST results from one-shot sequencing of a cloned cDNA. The cDNAs used for EST generation are typically individual clones from a cDNA library. The resulting sequence is a relatively low-quality fragment whose length is limited by current technology to approximately 500 to 800 nucleotides. Because these clones consist of DNA that is complementary to mRNA, the ESTs represent portions of expressed genes. They may be represented in databases as either cDNA/mRNA sequence or as the reverse complement of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Biology
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physical structure of biological macromolecules is known as molecular biology. Molecular biology was first described as an approach focused on the underpinnings of biological phenomena - uncovering the structures of biological molecules as well as their interactions, and how these interactions explain observations of classical biology. In 1945 the term molecular biology was used by physicist William Astbury. In 1953 Francis Crick, James Watson, Rosalind Franklin, and colleagues, working at Medical Research Council unit, Cavendish laboratory, Cambridge (now the MRC Laboratory of Molecular Biology), made a double helix model of DNA which changed the entire research scenario. They proposed the DNA structure based on previous research done by Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euphorbiaceae
Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as ''Euphorbia paralias'', are herbs, but some, especially in the tropics, are shrubs or trees, such as ''Hevea brasiliensis''. Some, such as ''Euphorbia canariensis'', are succulent and resemble cacti because of convergent evolution. This family has a cosmopolitan global distribution. The greatest diversity of species is in the tropics, however, the Euphorbiaceae also have many species in nontropical areas of all continents except Antarctica. Description The leaves are alternate, seldom opposite, with stipules. They are mainly simple, but where compound, are always palmate, never pinnate. Stipules may be reduced to hairs, glands, or spines, or in succulent species are sometimes absent. The plants can be monoecious or dioecious. The radially symmetrical flowers are unisexual, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clavulina Cristata
''Clavulina cristata'', commonly known as the white coral fungus or the crested coral fungus, is a white- or light-colored edible coral mushroom present in temperate areas of the Americas and Europe. It is the type species of the genus ''Clavulina''. The commonly used species name ''cristata'' was coined in 1790 by Danish mycologist Theodor Holmskjold (as ''Ramaria cristata''). However, Linnaeus described apparently the same fungus as ''Clavaria coralloides'' in Species plantarum in 1753. Therefore, according to the ''International Code of Nomenclature for algae, fungi, and plants'', the name ''Clavulina coralloides'' should be used in preference to ''Clavulina cristata'',See Kuo, M. (2007, April) the MushroomExpert.Com Web site entry although the latter name is in more common use. Description Fruit bodies, which are generally white- to cream-colored, can be up to tall, and broad. The coral "arms" are sparingly branched (3–4 times), 2–4 mm wide, smooth, and somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
