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Pristanic Acid
Pristanic acid (2,6,10,14-tetramethylpentadecanoic acid) is a terpenoid acid present at micromolar concentrations in the blood plasma of healthy individuals. It is also found in the lipids from many sources such as freshwater sponges, krill, earthworms, whales, human milk fat, bovine depot fat, butterfat or Californian petroleum. It is usually present in combination with phytanic acid. In humans, pristanic acid is obtained from two sources: either directly from the diet or as the alpha oxidation product of phytanic acid. At physiological concentrations pristanic acid is a natural ligand for peroxisome proliferator-activated receptor alpha (PPARα). In liver, pristanic acid is degraded by peroxisomal beta oxidation to propionyl-CoA. Together with phytanic acid, pristanic acid accumulates in several inherited disorders such as Zellweger syndrome. The salts and esters of pristanic acid are called pristanates. Pristanic acid was first isolated from butterfat by R. P. Hansen and J. D. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpenoid
The terpenoids, also known as isoprenoids, are a class of naturally occurring organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeably with "terpenes", terpenoids contain additional functional groups, usually containing oxygen. When combined with the hydrocarbon terpenes, terpenoids comprise about 80,000 compounds. They are the largest class of plant secondary metabolites, representing about 60% of known natural products. Many terpenoids have substantial pharmacological bioactivity and are therefore of interest to medicinal chemists. Plant terpenoids are used for their aromatic qualities and play a role in traditional herbal remedies. Terpenoids contribute to the scent of eucalyptus, the flavors of cinnamon, cloves, and ginger, the yellow color in sunflowers, and the red color in tomatoes. Well-known terpenoids include citral, menthol, camphor, salvinorin A in the plant '' Salvia di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxisome Proliferator-activated Receptor Alpha
Peroxisome proliferator-activated receptor alpha (PPAR-α), also known as NR1C1 (nuclear receptor subfamily 1, group C, member 1), is a nuclear receptor protein functioning as a transcription factor that in humans is encoded by the ''PPARA'' gene. Together with peroxisome proliferator-activated receptor delta and peroxisome proliferator-activated receptor gamma, PPAR-alpha is part of the subfamily of peroxisome proliferator-activated receptors. It was the first member of the PPAR family to be cloned in 1990 by Stephen Green and has been identified as the nuclear receptor for a diverse class of rodent Liver, hepatocarcinogens that causes proliferation of peroxisomes. Expression PPAR-α is primarily activated through ligand binding. Endogenous ligands include fatty acids such as arachidonic acid as well as other polyunsaturated fatty acids and various fatty acid-derived compounds such as certain members of the 15-hydroxyicosatetraenoic acid, 15-hydroxyeicosatetraenoic acid family ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the Roman Republic it became the dominant language in the Italian region and subsequently throughout the Roman Empire. Even after the fall of Western Rome, Latin remained the common language of international communication, science, scholarship and academia in Europe until well into the 18th century, when other regional vernaculars (including its own descendants, the Romance languages) supplanted it in common academic and political usage, and it eventually became a dead language in the modern linguistic definition. Latin is a highly inflected language, with three distinct genders (masculine, feminine, and neuter), six or seven noun cases (nominative, accusative, genitive, dative, ablative, and vocative), five declensions, four verb conjuga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (''Etmopterus perryi''), a deep sea species that is only in length, to the whale shark (''Rhincodon typus''), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths up to . They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and fresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or exemplified by the odors of gasoline and lighter fluid. They occur in a diverse range of molecular structures and phases: they can be gases (such as methane and propane), liquids (such as hexane and benzene), low melting solids (such as paraffin wax and naphthalene) or polymers (such as polyethylene and polystyrene). In the fossil fuel industries, ''hydrocarbon'' refers to the naturally occurring petroleum, natural gas and coal, and to their hydrocarbon derivatives and purified forms. Combustion of hydrocarbons is the main source of the world's energy. Petroleum is the dominant raw-material source for organic commodity chemicals such as solvents and polymers. Most anthropogenic (human-generated) emissions of greenhouse gases are carbon di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pristane
Pristane is a natural saturated terpenoid alkane obtained primarily from shark liver oil, from which its name is derived (Latin ''pristis'', "shark"). It is also found in the stomach oil of birds in the order Procellariiformes and in mineral oil and some foods. Pristane and phytane are used in the fields of geology and environmental science as biomarkers to characterize origins and evolution of petroleum hydrocarbons and coal. It is a transparent oily liquid that is immiscible with water, but soluble in diethyl ether, benzene, chloroform and carbon tetrachloride. Pristane is known to induce autoimmune diseases in rodents. It is used in research to understand the pathogenesis of rheumatoid arthritis and lupus. It is used as a lubricant, a transformer oil, an immunologic adjuvant, and an anti-corrosion agent, biological marker, plasmocytomas inducer and in production of monoclonal antibodies. Biosynthetically, pristane is derived from phytol and is used as a biomarker in petroleum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butterfat
Butterfat or milkfat is the fatty portion of milk. Milk and cream are often sold according to the amount of butterfat they contain. Composition Butterfat is mainly composed of triglycerides. Each triglyceride contains three fatty acids. Butterfat triglycerides contain the following amounts of fatty acids (by mass fraction):The quote values vary by 1–3% according to the source: Butterfat contains about 3% trans fat, which is slightly less than 0.5 grams per US tablespoon. Trans fats occur naturally in meat and milk from ruminants. The predominant kind of trans fat found in milk is vaccenic fatty acid. Trans fats may be also found in some industrially produced foods, such as shortenings obtained by hydrogenation of vegetable oils. In light of recognized scientific evidence, nutritional authorities consider all trans fats equally harmful for health and recommend that their consumption be reduced to trace amounts. However, two Canadian studies have shown that vaccenic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zellweger Syndrome
Zellweger syndrome is a rare congenital disorder characterized by the reduction or absence of functional peroxisomes in the cells of an individual. It is one of a family of disorders called Zellweger spectrum disorders which are leukodystrophies. Zellweger syndrome is named after Hans Zellweger (1909–1990), a Swiss-American pediatrician, a professor of pediatrics and genetics at the University of Iowa who researched this disorder. Signs and symptoms Zellweger syndrome is one of three peroxisome biogenesis disorders which belong to the Zellweger spectrum of peroxisome biogenesis disorders (PBD-ZSD). The other two disorders are neonatal adrenoleukodystrophy (NALD), and infantile Refsum disease (IRD). Although all have a similar molecular basis for disease, Zellweger syndrome is the most severe of these three disorders. Zellweger syndrome is associated with impaired neuronal migration, neuronal positioning, and brain development. In addition, individuals with Zellweger syndr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propionyl-CoA
Propionyl-CoA is a coenzyme A derivative of propionic acid. It is composed of a 24 total carbon chain (without the coenzyme, it is a 3 carbon structure) and its production and metabolic fate depend on which organism it is present in. Several different pathways can lead to its production, such as through the catabolism of specific amino acids or the oxidation of odd-chain fatty acids. It later can be broken down by propionyl-CoA carboxylase or through the methylcitrate cycle. In different organisms, however, propionyl-CoA can be sequestered into controlled regions, to alleviate its potential toxicity through accumulation. Genetic deficiencies regarding the production and breakdown of propionyl-CoA also have great clinical and human significance. Production There are several different pathways through which propionyl-CoA can be produced: * Propionyl-CoA, a three-carbon structure, is considered to be a minor species of propionic acid. Therefore, odd-number chains of fatty acids are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Oxidation
In biochemistry and metabolism, beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA, which enters the citric acid cycle, and NADH and FADH2, which are co-enzymes used in the electron transport chain. It is named as such because the beta carbon of the fatty acid undergoes oxidation to a carbonyl group. Beta-oxidation is primarily facilitated by the mitochondrial trifunctional protein, an enzyme complex associated with the inner mitochondrial membrane, although very long chain fatty acids are oxidized in peroxisomes. The overall reaction for one cycle of beta oxidation is: :C''n''-acyl-CoA + FAD + + + CoA → C''n''-2-acyl-CoA + + NADH + + acetyl-CoA Activation and membrane transport Free fatty acids cannot penetrate any biological membrane due to their negative charge. Free fatty acids must cross the cell membrane through specific transport pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxisome
A peroxisome () is a membrane-bound organelle, a type of microbody, found in the cytoplasm of virtually all eukaryotic cells. Peroxisomes are oxidative organelles. Frequently, molecular oxygen serves as a co-substrate, from which hydrogen peroxide (H2O2) is then formed. Peroxisomes owe their name to hydrogen peroxide generating and scavenging activities. They perform key roles in lipid metabolism and the conversion of reactive oxygen species. Peroxisomes are involved in the catabolism of very long chain fatty acids, branched chain fatty acids, bile acid intermediates (in the liver), D-amino acids, and polyamines, the reduction of reactive oxygen species – specifically hydrogen peroxide – and the biosynthesis of plasmalogens, i.e., ether phospholipids critical for the normal function of mammalian brains and lungs. They also contain approximately 10% of the total activity of two enzymes (Glucose-6-phosphate dehydrogenase and 6-Phosphogluconate dehydrogenase) in the pentose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Oxidation
Enzymatic steps of alpha oxidation, 250px Alpha oxidation (α-oxidation) is a process by which certain branched-chain fatty acids are broken down by removal of a single carbon from the carboxyl end. In humans, alpha-oxidation is used in peroxisomes to break down dietary phytanic acid, which cannot undergo beta-oxidation due to its β-methyl branch, into pristanic acid. Pristanic acid can then acquire acetyl-CoA and subsequently become beta oxidized, yielding propionyl-CoA. Pathway Alpha-oxidation of phytanic acid is believed to take place entirely within peroxisomes. #Phytanic acid is first attached to CoA to form phytanoyl-CoA. # Phytanoyl-CoA is oxidized by phytanoyl-CoA dioxygenase, in a process using Fe2+ and O2, to yield 2-hydroxyphytanoyl-CoA. #2-hydroxyphytanoyl-CoA is cleaved by 2-hydroxyphytanoyl-CoA lyase in a TPP-dependent reaction to form pristanal and formyl-CoA (in turn later broken down into formate and eventually CO2). #Pristanal is oxidized by aldehyde dehydr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
