Cyclopropane fatty acids (CPA) are a subgroup of fatty acids that contain a cyclopropane group. [1] Although they are usually rare, the seed oil from lychee contains nearly 40% CPAs in the form of triglycerides. [2]
Cyclopropane fatty acids (CPA) are a subgroup of fatty acids that contain a cyclopropane group. [1] Although they are usually rare, the seed oil from lychee contains nearly 40% CPAs in the form of triglycerides. [2]
CPAs are derived from unsaturated fatty acids by cyclopropanation. The methylene donor is a methyl group on S-adenosylmethionine (SAM). The conversion is catalyzed by cyclopropane-fatty-acyl-phospholipid synthase. [3] The mechanism is proposed to involve transfer of a CH3+ group from SAM to the alkene, followed by deprotonation of the newly attached methyl group and ring closure. [4]
Cyclopropene fatty acids are even rarer than CPAs. The best-known examples are malvalic acid and sterculic acid. A triglyceride made of 3 sterculic acid molecules esterified with glycerol is present in Sterculia foetida seed oil (in amounts greater than 60%) and at low levels in the seed oil of other species of Malvaceae [a] (~12%), cottonseed oil (~1%). The cyclopropene ring is destroyed during refining and hydrogenation of the oils. They have attracted interest because they reduce levels of the enzyme stearoyl-CoA 9-desaturase (SCD), which catalyzes the biodesaturation of stearic acid to oleic acid. [7]
At least one review indicates that CPFA's are carcinogenic. [8]
Lipids are a broad group of organic compounds which include fats, waxes, sterols, fat-soluble vitamins, 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.
A triglyceride is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and other vertebrates as well as vegetable fat. They are also present in the blood to enable the bidirectional transference of adipose fat and blood glucose from the liver and are a major component of human skin oils.
Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish due to the presence of impurities. In chemical terms, oleic acid is classified as a monounsaturated omega-9 fatty acid, abbreviated with a lipid number of 18:1 cis-9, and a main product of Δ9-desaturase. It has the formula CH3−(CH2)7−CH=CH−(CH2)7−COOH. The name derives from the Latin word oleum, which means oil. It is the most common fatty acid in nature. The salts and esters of oleic acid are called oleates. It is a common component of oils, and thus occurs in many types of food, as well as in soap.
Biodiesel production is the process of producing the biofuel, biodiesel, through the chemical reactions of transesterification and esterification. This process renders a product (chemistry) and by-products.
Cyclopropene is an organic compound with the formula C3H4. It is the simplest cycloalkene. Because the ring is highly strained, cyclopropene is difficult to prepare and highly reactive. This colorless gas has been the subject for many fundamental studies of bonding and reactivity. It does not occur naturally, but derivatives are known in some fatty acids. Derivatives of cyclopropene are used commercially to control ripening of some fruit.
Sebacic acid is a naturally occurring dicarboxylic acid with the chemical formula HO2C(CH2)8CO2H. It is a white flake or powdered solid. Sebaceus is Latin for tallow candle, sebum is Latin for tallow, and refers to its use in the manufacture of candles. Sebacic acid is a derivative of castor oil.
Eicosapentaenoic acid (EPA; also icosapentaenoic acid) is an omega−3 fatty acid. In physiological literature, it is given the name 20:5(n−3). It also has the trivial name timnodonic acid. In chemical structure, EPA is a carboxylic acid with a 20-carbon chain and five cis double bonds; the first double bond is located at the third carbon from the omega end.
Sabinene is a natural bicyclic monoterpene with the molecular formula C10H16. It is isolated from the essential oils of a variety of plants including Marjoram, holm oak (Quercus ilex) and Norway spruce (Picea abies). It has a strained ring system with a cyclopentane ring fused to a cyclopropane ring.
Monoglycerides are a class of glycerides which are composed of a molecule of glycerol linked to a fatty acid via an ester bond. As glycerol contains both primary and secondary alcohol groups two different types of monoglycerides may be formed; 1-monoacylglycerols where the fatty acid is attached to a primary alcohol, or a 2-monoacylglycerols where the fatty acid is attached to the secondary alcohol.
Fatty acid desaturases are a family of enzymes that convert saturated fatty acids into unsaturated fatty acids and polyunsaturated fatty acids. For the common fatty acids of the C18 variety, desaturases convert stearic acid into oleic acid. Other desaturases convert oleic acid into linoleic acid, which is the precursor to alpha-linolenic acid, gamma-linolenic acid, and eicosatrienoic acid.
In organic chemistry, cyclopropanation refers to any chemical process which generates cyclopropane rings. It is an important process in modern chemistry as many useful compounds bear this motif; for example pyrethroid insecticides and a number of quinolone antibiotics. However, the high ring strain present in cyclopropanes makes them challenging to produce and generally requires the use of highly reactive species, such as carbenes, ylids and carbanions. Many of the reactions proceed in a cheletropic manner.
Squalene synthase (SQS) or farnesyl-diphosphate:farnesyl-diphosphate farnesyl transferase is an enzyme localized to the membrane of the endoplasmic reticulum. SQS participates in the isoprenoid biosynthetic pathway, catalyzing a two-step reaction in which two identical molecules of farnesyl pyrophosphate (FPP) are converted into squalene, with the consumption of NADPH. Catalysis by SQS is the first committed step in sterol synthesis, since the squalene produced is converted exclusively into various sterols, such as cholesterol, via a complex, multi-step pathway. SQS belongs to squalene/phytoene synthase family of proteins.
Malvalic acid is a cyclopropene fatty acid found in baobab seed oil and cottonseed oil. This unusual molecule is thought to be one of the causes of abnormalities that develop in animals that ingest cottonseed oil. Refining processes, such as hydrogenation, can remove or destroy malvalic acid.
In enzymology, a cyclopropane-fatty-acyl-phospholipid synthase is an enzyme that catalyzes the chemical reaction
Nervonic acid is a fatty acid. It is a monounsaturated analog of lignoceric acid (24:0). It is also known as selacholeic acid and cis-15-tetracosenoic acid. Its name derives from the Latin word nervus, meaning nerve or sinew.
A diglyceride, or diacylglycerol (DAG), is a glyceride consisting of two fatty acid chains covalently bonded to a glycerol molecule through ester linkages. Two possible forms exist, 1,2-diacylglycerols and 1,3-diacylglycerols. Diglycerides are natural components of food fats, though minor in comparison to triglycerides. DAGs can act as surfactants and are commonly used as emulsifiers in processed foods. DAG-enriched oil has been investigated extensively as a fat substitute due to its ability to suppress the accumulation of body fat; with total annual sales of approximately USD 200 million in Japan since its introduction in the late 1990s till 2009.
Sterculia foetida is a soft wooded tree that can grow up to 35 metres tall. Common names for the plant are the bastard poon tree, Java olive tree, hazel sterculia, wild almond tree, and skunk tree.
Methylene cyclopropyl acetic acid (MCPA) is found in lychee seeds and also a toxic metabolite in mammalian digestion after eating hypoglycin, present in the unripe ackee fruit, grown in Jamaica and in Africa. By blocking coenzyme A and carnitine, MPCA causes a decrease in β-oxidation of fatty acids, and hence gluconeogenesis.
Sterculic acid is a cyclopropene fatty acid. It is found in various plants of the genus Sterculia, including being the main component of Sterculia foetida seed oil.
Lactobacillic aci, scientifically 10-(2-hexylcyclopropyl) decanoic acid, is a naturally occurring chemical compound from the group of fatty acids. Its salts are called lactobacillates. A special feature is the cyclopropane ring in the carbon chain. Lactobacillic acid, with 19 carbon atoms, is a fatty acid with an odd number of carbon atoms.