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47-437: DHA , Dha and dha may refer to: Chemicals [ edit ] Docosahexaenoic acid , a 22:6 omega-3 fatty acid Dehydroandrosterone , an endogenous androgenic steroid Dehydroascorbic acid , an oxidized form of ascorbic acid Dehydroacetic acid , a pyrone derivative used as a plasticiser, as a fungicide, as a bactericide, and as a food preservative Dihydroxyacetone ,

94-401: A carboxylic acid is an organic acid that contains a carboxyl group ( −C(=O)−OH ) attached to an R-group . The general formula of a carboxylic acid is often written as R−COOH or R−CO 2 H , sometimes as R−C(O)OH with R referring to an organyl group (e.g., alkyl , alkenyl , aryl ), or hydrogen , or other groups. Carboxylic acids occur widely. Important examples include

141-422: A neuronal plasma membrane is composed of DHA. DHA modulates the carrier-mediated transport of choline, glycine, and taurine, the function of delayed rectifier potassium channels , and the response of rhodopsin contained in the synaptic vesicles . Phosphatidylserine (PS) – which contains high DHA content – has roles in neuronal signaling and neurotransmitter synthesis, and DHA deficiency

188-407: A of acetic acid is 4.76 whereas trifluoroacetic acid, with a trifluoromethyl substituent , has a p K a of 0.23). Electron-donating substituents give weaker acids (the p K a of formic acid is 3.75 whereas acetic acid, with a methyl substituent , has a p K a of 4.76) Deprotonation of carboxylic acids gives carboxylate anions; these are resonance stabilized , because the negative charge

235-437: A base and deprotonates the acid. A second equivalent will attack the carbonyl group to create a geminal alkoxide dianion, which is protonated upon workup to give the hydrate of a ketone. Because most ketone hydrates are unstable relative to their corresponding ketones, the equilibrium between the two is shifted heavily in favor of the ketone. For example, the equilibrium constant for the formation of acetone hydrate from acetone

282-515: A broad range of cell membrane and cell signaling properties, particularly in grey matter and retinal photoreceptor cell outer segments, which are rich in membranes. A systematic review found that DHA had no significant benefits in improving visual field in individuals with retinitis pigmentosa . Animal research shows effect of oral intake of deuterium-reinforced DHA (D-DHA) for prevention of macular degeneration . Omega−3 PUFAs such as DHA and eicosapentaenoic acid (EPA) are effective in

329-428: A carboxylic acid, the carboxyl can be considered position one of the parent chain even if there are other substituents , such as 3-chloropropanoic acid . Alternately, it can be named as a "carboxy" or "carboxylic acid" substituent on another parent structure, such as 2-carboxyfuran . The carboxylate anion ( R−COO or R−CO − 2 ) of a carboxylic acid is usually named with the suffix -ate , in keeping with

376-426: A chlorine atom using thionyl chloride to give acyl chlorides . In nature, carboxylic acids are converted to thioesters . Thionyl chloride can be used to convert carboxylic acids to their corresponding acyl chlorides. First, carboxylic acid 1 attacks thionyl chloride, and chloride ion leaves. The resulting oxonium ion 2 is activated towards nucleophilic attack and has a good leaving group, setting it apart from

423-678: A glyph in the Brahmic family of script Dha (Javanese) (ꦝ), a letter in the Javanese script Other [ edit ] Dha, Ladakh , a village in the Leh district of India. Dhahran International Airport , military airbase in Dhahran, Saudi Arabia Dha (sword) , a single-edged weapon found in Burma/Myanmar, Thailand and other parts of Southeast Asia Directory Harvest Attack ,

470-420: A good direct source. Beef brain, for example, contains approximately 855 mg of DHA per 100 grams in a serving. While DHA may be the primary fatty acid found in certain specialized tissues, these tissues, aside from the brain, are typically small in size, such as the seminiferous tubules and the retina. As a result, animal-based foods, excluding the brain, generally offer minimal amounts of preformed DHA. In

517-873: A large scale. They are also frequently found in nature. Esters of fatty acids are the main components of lipids and polyamides of aminocarboxylic acids are the main components of proteins . Carboxylic acids are used in the production of polymers, pharmaceuticals, solvents, and food additives. Industrially important carboxylic acids include acetic acid (component of vinegar, precursor to solvents and coatings), acrylic and methacrylic acids (precursors to polymers, adhesives), adipic acid (polymers), citric acid (a flavor and preservative in food and beverages), ethylenediaminetetraacetic acid (chelating agent), fatty acids (coatings), maleic acid (polymers), propionic acid (food preservative), terephthalic acid (polymers). Important carboxylate salts are soaps. In general, industrial routes to carboxylic acids differ from those used on

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564-531: A low solubility in water (0.2 g/L), but its sodium salt is very soluble in water. Carboxylic acids tend to have higher boiling points than water, because of their greater surface areas and their tendency to form stabilized dimers through hydrogen bonds . For boiling to occur, either the dimer bonds must be broken or the entire dimer arrangement must be vaporized, increasing the enthalpy of vaporization requirements significantly. Carboxylic acids are Brønsted–Lowry acids because they are proton (H ) donors. They are

611-662: A method used by spammers to obtain email addresses Disarmament as Humanitarian Action , a research project carried out at the United Nations Institute for Disarmament Research Doctor of Health Administration , a doctoral degree D.Ha., an abbreviation used for the United States District Court for the District of Hawaii Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

658-523: A normal carboxylic acid. In the next step, 2 is attacked by chloride ion to give tetrahedral intermediate 3 , a chlorosulfite. The tetrahedral intermediate collapses with the loss of sulfur dioxide and chloride ion, giving protonated acyl chloride 4 . Chloride ion can remove the proton on the carbonyl group, giving the acyl chloride 5 with a loss of HCl . [REDACTED] Phosphorus(III) chloride (PCl 3 ) and phosphorus(V) chloride (PCl 5 ) will also convert carboxylic acids to acid chlorides, by

705-619: A quality product that is kept cold in storage and then keeping it in a refrigerator can help minimize oxidation. As optimal DHA level is important for brain development and maturation, there are established daily recommendations for DHA intake in children. The table below shows the daily DHA / DHA + EPA intake recommended for children of different ages: Experts recommend DHA intake of 10–12 mg/day for children 12–24 months, 100–150 mg/day of DHA+EPA for children 2–4 years old and 150–200 mg/day of DHA+EPA for children 4–6 years old. Carboxylic acid In organic chemistry ,

752-483: A sharp band associated with vibration of the C=O carbonyl bond ( ν C=O ) between 1680 and 1725 cm . A characteristic ν O–H band appears as a broad peak in the 2500 to 3000 cm region. By H NMR spectrometry, the hydroxyl hydrogen appears in the 10–13 ppm region, although it is often either broadened or not observed owing to exchange with traces of water. Many carboxylic acids are produced industrially on

799-474: A similar mechanism. One equivalent of PCl 3 can react with three equivalents of acid, producing one equivalent of H 3 PO 3 , or phosphorus acid , in addition to the desired acid chloride. PCl 5 reacts with carboxylic acids in a 1:1 ratio, and produces phosphorus(V) oxychloride (POCl 3 ) and hydrogen chloride (HCl) as byproducts. Carboxylic acids react with Grignard reagents and organolithiums to form ketones. The first equivalent of nucleophile acts as

846-406: A smaller scale because they require specialized equipment. Preparative methods for small scale reactions for research or for production of fine chemicals often employ expensive consumable reagents. Many reactions produce carboxylic acids but are used only in specific cases or are mainly of academic interest. Carboxylic acids react with bases to form carboxylate salts, in which the hydrogen of

893-701: A Δ4-desaturase, it is considered outdated. Marine bacteria and the microalgae Schizochytrium use an anerobic polyketide synthase pathway to synthesize DHA. DHA can be metabolized into DHA-derived specialized pro-resolving mediators (SPMs), DHA epoxides, electrophilic oxo-derivatives (EFOX) of DHA, neuroprostanes, ethanolamines, acylglycerols, docosahexaenoyl amides of amino acids or neurotransmitters, and branched DHA esters of hydroxy fatty acids, among others. The enzyme CYP2C9 metabolizes DHA to epoxydocosapentaenoic acids (EDPs; primarily 19,20-epoxy-eicosapentaenoic acid isomers [i.e. 10,11-EDPs]). Though mixed and plagued by methodological inconsistencies, there

940-610: Is a carboxylic acid (- oic acid ) with a 22- carbon chain ( docosa- derives from the Ancient Greek for 22) and six ( hexa- ) cis double bonds ( -en- ); with the first double bond located at the third carbon from the omega end. Its trivial name is cervonic acid (from the Latin word cerebrum for "brain"), its systematic name is all-cis-docosa-4,7,10,13,16,19-hexa-enoic acid . In organisms that do not eat algae containing DHA nor animal products containing DHA, DHA

987-511: Is a highly chemoselective agent for carboxylic acid reduction. It selectively activates the carboxylic acid to give the carboxymethyleneammonium salt, which can be reduced by a mild reductant like lithium tris( t -butoxy)aluminum hydride to afford an aldehyde in a one pot procedure. This procedure is known to tolerate reactive carbonyl functionalities such as ketone as well as moderately reactive ester, olefin, nitrile, and halide moieties. The hydroxyl group on carboxylic acids may be replaced with

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1034-514: Is a major fatty acid in brain phospholipids and the retina . Preliminary research has investigated its potential benefit in Alzheimer's disease , and cardiovascular disease , and other disorders. DHA is the most abundant omega−3 fatty acid in the brain and retina. DHA comprises 40% of the polyunsaturated fatty acids (PUFAs) in the brain and 60% of the PUFAs in the retina. Fifty percent of

1081-521: Is associated with cognitive decline. DHA levels are reduced in the brain tissue of severely depressed people. Aerobic eukaryotes, specifically microalgae, mosses , fungi , and some animals, perform biosynthesis of DHA as a series of desaturation and elongation reactions, catalyzed by the sequential action of desaturase and elongase enzymes . This pathway, originally identified in Thraustochytrium , applies to these groups: In humans, DHA

1128-496: Is associated with its role in cardiovascular protection and lowering the risk of coronary artery disease. DHA supplementation has been shown to improve high-density lipoprotein (‘good cholesterol’), and lower total cholesterol as well as blood pressure levels. Foods high in omega−3 fatty acids may be recommended to women who want to become pregnant or when nursing. A working group from the International Society for

1175-533: Is delocalized over the two oxygen atoms, increasing the stability of the anion. Each of the carbon–oxygen bonds in the carboxylate anion has a partial double-bond character. The carbonyl carbon's partial positive charge is also weakened by the - / 2 negative charges on the 2 oxygen atoms. Carboxylic acids often have strong sour odours. Esters of carboxylic acids tend to have fruity, pleasant odours, and many are used in perfume . Carboxylic acids are readily identified as such by infrared spectroscopy . They exhibit

1222-488: Is either obtained from the diet or may be converted in small amounts from eicosapentaenoic acid (EPA, 20:5, ω-3). With the identification of FADS2 as a human Δ4-desaturase in 2015, it is now known that humans also follow the whole "aerobic eukaryote" pathway, involving Δ5-elongation to DPA and Δ4-desaturation to DHA. A "Sprecher's shunt" hypothesis, proposed in 1991, postulates that EPA is twice elongated to 24:5 ω-3, then desaturated to 24:6 ω-3 (via delta 6 desaturase ) in

1269-449: Is instead produced internally from α-linolenic acid , a shorter omega−3 fatty acid manufactured by plants (and also occurring in animal products as obtained from plants). Limited amounts of eicosapentaenoic and docosapentaenoic acids are possible products of α-linolenic acid metabolism in young women and men. DHA in breast milk is important for the developing infant. Rates of DHA production in women are 15% higher than in men. DHA

1316-485: Is little evidence of adverse health or cognitive effects due to DHA deficiency in adult vegetarians or vegans, breast milk levels remain a concern for supplying adequate DHA to the infant. Fish oil is widely sold in capsules containing a mixture of omega−3 fatty acids, including EPA and DHA. Oxidized fish oil in supplement capsules may contain lower levels of EPA and DHA. Light, oxygen exposure, and heat can all contribute to oxidation of fish oil supplements. Buying

1363-431: Is now convincing evidence from ecological, RCTs, meta-analyses and animal trials show a benefit for omega−3 dietary intake for cardiovascular health. Of the n −3 FAs, DHA has been argued to be the most beneficial due to its preferential uptake in the myocardium, its strongly anti-inflammatory activity and its metabolism toward neuroprotectins and resolvins, the latter of which directly contribute to cardiac function. DHA

1410-496: Is only useful for forming methyl esters. Like esters , most carboxylic acids can be reduced to alcohols by hydrogenation , or using hydride transferring agents such as lithium aluminium hydride . Strong alkyl transferring agents, such as organolithium compounds but not Grignard reagents , will reduce carboxylic acids to ketones along with transfer of the alkyl group. The Vilsmaier reagent ( N , N -Dimethyl(chloromethylene)ammonium chloride; [ClHC=N (CH 3 ) 2 ]Cl )

1457-464: The amino acids and fatty acids . Deprotonation of a carboxylic acid gives a carboxylate anion . Carboxylic acids are commonly identified by their trivial names . They often have the suffix -ic acid . IUPAC -recommended names also exist; in this system, carboxylic acids have an -oic acid suffix. For example, butyric acid ( CH 3 CH 2 CH 2 CO 2 H ) is butanoic acid by IUPAC guidelines. For nomenclature of complex molecules containing

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1504-552: The hydroxyl (–OH) group is replaced with a metal cation . For example, acetic acid found in vinegar reacts with sodium bicarbonate (baking soda) to form sodium acetate , carbon dioxide , and water: Widely practiced reactions convert carboxylic acids into esters , amides , carboxylate salts , acid chlorides , and alcohols . Their conversion to esters is widely used, e.g. in the production of polyesters . Likewise, carboxylic acids are converted into amides , but this conversion typically does not occur by direct reaction of

1551-759: The Australian Defence Forces Defence Housing Authority , provides commercial and residential housing developments for the Pakistani army Defence Housing Authority, Islamabad Defence Housing Authority, Karachi Defense Health Agency , the United States Department of Defense agency responsible for managing the activities of the Military Health System Department of Humanitarian Affairs, now known as

1598-502: The Study of Fatty Acids and Lipids recommended 300 mg/day of DHA for pregnant and lactating women, whereas the average consumption was between 45 mg and 115 mg per day of the women in the study, similar to a Canadian study. A major structural component of the mammalian central nervous system, DHA is the most abundant omega−3 fatty acid in the brain and retina. Brain and retinal function rely on dietary intake of DHA to support

1645-728: The United Nations Office for the Coordination of Humanitarian Affairs DHA Cinema , a movie theatre in Lahore, Pakistan District health authority , a former type of administrative organisation of the NHS in England and Wales Drug Houses of Australia , a Singapore pharmaceuticals manufacturer Demirören Haber Ajansı ( Demirören News Agency ), a Turkish news agency Linguistics [ edit ] Dha (Indic) ,

1692-423: The active ingredient in sunless or self-tanning skincare products 9,10-Dihydroanthracene , a form of anthracene whose center-ring carbons have been reduced Dihydroartemisinin , an antimalarial Dihydroalprenolol , a beta-adrenergic blocker Dehydroalanine , an uncommon unsaturated α-amino acid Organizations [ edit ] Defence Housing Australia , a provider of family housing for members of

1739-422: The carboxylic acid and the amine. Instead esters are typical precursors to amides. The conversion of amino acids into peptides is a significant biochemical process that requires ATP . Converting a carboxylic acid to an amide is possible, but not straightforward. Instead of acting as a nucleophile, an amine will react as a base in the presence of a carboxylic acid to give the ammonium carboxylate salt. Heating

1786-405: The early 1980s, NASA sponsored scientific research on a plant-based food source that could generate oxygen and nutrition on long-duration space flights . Certain species of marine algae produced rich nutrients, leading to the development of an algae-based, vegetable-like oil that contains two polyunsaturated fatty acids, DHA and arachidonic acid . DHA is widely used as a food supplement . It

1833-471: The formation of the anhydride via condensation is an equilibrium process. Under acid-catalyzed conditions, carboxylic acids will react with alcohols to form esters via the Fischer esterification reaction, which is also an equilibrium process. Alternatively, diazomethane can be used to convert an acid to an ester. While esterification reactions with diazomethane often give quantitative yields, diazomethane

1880-576: The general pattern of -ic acid and -ate for a conjugate acid and its conjugate base, respectively. For example, the conjugate base of acetic acid is acetate . Carbonic acid , which occurs in bicarbonate buffer systems in nature, is not generally classed as one of the carboxylic acids, despite that it has a moiety that looks like a COOH group. Carboxylic acids are polar . Because they are both hydrogen-bond acceptors (the carbonyl −C(=O)− ) and hydrogen-bond donors (the hydroxyl −OH ), they also participate in hydrogen bonding . Together,

1927-593: The hydroxyl and carbonyl group form the functional group carboxyl. Carboxylic acids usually exist as dimers in nonpolar media due to their tendency to "self-associate". Smaller carboxylic acids (1 to 5 carbons) are soluble in water, whereas bigger carboxylic acids have limited solubility due to the increasing hydrophobic nature of the alkyl chain. These longer chain acids tend to be soluble in less-polar solvents such as ethers and alcohols. Aqueous sodium hydroxide and carboxylic acids, even hydrophobic ones, react to yield water-soluble sodium salts. For example, enanthic acid has

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1974-456: The mitochondria, then shortened to DHA (22:6 ω-3) via beta oxidation in the peroxisome . The hypothesis became accepted for a while because scientists have (until 2015) long tried and failed to find a Δ4-desaturase in mammals. However, the shunt model does not match clinical data, specifically as patients with beta oxidation defects do not display issues in DHA synthesis. With the identification of

2021-476: The most common type of organic acid . Carboxylic acids are typically weak acids , meaning that they only partially dissociate into [H 3 O] cations and R−CO − 2 anions in neutral aqueous solution. For example, at room temperature, in a 1- molar solution of acetic acid , only 0.001% of the acid are dissociated (i.e. 10 moles out of 1 mol). Electron-withdrawing substituents, such as -CF 3 group , give stronger acids (the p K

2068-441: The prevention and treatment of asthma and allergic diseases. Ordinary types of cooked salmon contain 500–1500 mg DHA and 300–1000 mg EPA per 100 grams. Additional rich seafood sources of DHA include caviar (3400 mg per 100 grams), anchovies (1292 mg per 100 grams), mackerel (1195 mg per 100 grams), and cooked herring (1105 mg per 100 grams). Brains from mammals taken as food are also

2115-415: The salt to above 100 °C will drive off water and lead to the formation of the amide. This method of synthesizing amides is industrially important, and has laboratory applications as well. In the presence of a strong acid catalyst, carboxylic acids can condense to form acid anhydrides. The condensation produces water, however, which can hydrolyze the anhydride back to the starting carboxylic acids. Thus,

2162-463: The title DHA . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=DHA&oldid=1237808458 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Docosahexaenoic acid Structurally, DHA

2209-640: Was first used primarily in infant formulas. In 2019, the US Food and Drug Administration published qualified health claims for DHA. Some manufactured DHA is a vegetarian product extracted from algae, and it competes on the market with fish oil that contains DHA and other omega−3s such as EPA . Both fish oil and DHA are odorless and tasteless after processing as a food additive. Vegetarian diets typically contain limited amounts of DHA, and vegan diets typically contain no DHA. In preliminary research, algae-based supplements increased DHA levels. While there

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