{{not to be confused|Caproic acid|Capric acid}} {{Short description|Fatty acid (CH3–(CH2)6–COOH)}} {{Chembox |Watchedfields = changed |verifiedrevid = 443496721 |ImageFile = Caprylic acid.svg |ImageClass = skin-invert |ImageName = Skeletal formula |ImageFile1 = Caprylic-acid-3D-balls.png |ImageClass1 = bg-transparent |ImageName1 = Ball-and-stick model |PIN = Octanoic acid |OtherNames = 1-Heptanecarboxylic acid<br />Octylic acid<br />Octoic acid<br />C8:0 (lipid numbers) |Section1 = {{Chembox Identifiers |IUPHAR_ligand = 4585 |UNII_Ref = {{fdacite|correct|FDA}} |UNII = OBL58JN025 |KEGG_Ref = {{keggcite|correct|kegg}} |KEGG = D05220 |InChI = 1/C8H16O2/c1-2-3-4-5-6-7-8(9)10/h2-7H2,1H3,(H,9,10) |InChIKey = WWZKQHOCKIZLMA-UHFFFAOYAH |ChEMBL_Ref = {{ebicite|correct|EBI}} |ChEMBL = 324846 |StdInChI_Ref = {{stdinchicite|correct|chemspider}} |StdInChI = 1S/C8H16O2/c1-2-3-4-5-6-7-8(9)10/h2-7H2,1H3,(H,9,10) |StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} |StdInChIKey = WWZKQHOCKIZLMA-UHFFFAOYSA-N |CASNo_Ref = {{cascite|correct|CAS}} |CASNo = 124-07-2 |PubChem = 379 |ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} |ChemSpiderID = 370 |DrugBank_Ref = {{drugbankcite|correct|drugbank}} |DrugBank = DB04519 |ChEBI_Ref = {{ebicite|correct|EBI}} |ChEBI = 28837 |SMILES = CCCCCCCC(=O)O |EINECS = 204-677-5 }} |Section2 = {{Chembox Properties |C = 8 | H = 16 | O = 2 |MolarMassUnit = g/mol |Appearance = Oily colorless liquid |Odor = Faint, fruity-acid; irritating |Density = 0.910&nbsp;g/cm<sup>3</sup><ref name=Merck/> |MeltingPtC = 16.7 |MeltingPt_ref = <ref name="lexicon">{{cite journal |year=2001 |title=Lexicon of lipid nutrition (IUPAC Technical Report) |journal=Pure and Applied Chemistry |volume=73 |issue=4 |pages=685–744 |doi=10.1351/pac200173040685 |doi-access=free |last1=Beare-Rogers |first1=J. |last2=Dieffenbacher |first2=A. |last3=Holm |first3=J.V. |s2cid=84492006 }}</ref> |BoilingPtC = 239.7 |BoilingPt_ref = <ref name=Merck>{{Merck12th}}</ref> |Solubility = 0.068&nbsp;g/100 mL<ref name=Merck/> |SolubleOther = Soluble in alcohol, chloroform, ether, CS<sub>2</sub>, petroleum ether, acetonitrile |pKa = {{ubli |4.89<ref name=crc>{{cite book | author=Lide, D.R. (Ed.) | title=CRC Handbook of Chemistry and Physics (70th Edn.) | publisher=Boca Raton (FL):CRC Press | year=1990}}</ref> |1.055 (2.06–2.63&nbsp;K) |1.53 (−191&nbsp;°C) }} |LogP = 3.05 |RefractIndex = 1.4285 |VaporPressure = 0.25&nbsp;Pa |MagSus = −101.60·10<sup>−6</sup>&nbsp;cm<sup>3</sup>/mol }} |Section3 = {{Chembox Thermochemistry |DeltaHf = −636&nbsp;kJ/mol |HeatCapacity = 297.9&nbsp;J/K·mol }} |Section4 = {{Chembox Hazards |FlashPtC = 130 |AutoignitionPtC = 440 |NFPA-H = 3 | NFPA-F = 0 | NFPA-R = 1 | NFPA-S = COR |LD50 = 10.08&nbsp;g/kg (orally in rats)<ref name=Merck/> |GHSPictograms = {{GHS05}}<ref name="sigma">{{Sigma-Aldrich| id= w279927|name=Octanoic acid|accessdate=2022-08-11}}</ref> |GHSSignalWord = Danger |HPhrases = {{H-phrases|314}} |PPhrases = {{P-phrases|264|280|301+330+331|303+361+353|304+340+310|305+351+338+310|363|405|501}} }} |Section5 = {{Chembox Related |OtherCompounds = Heptanoic acid, nonanoic acid }} }}

'''Caprylic acid''' ({{ety|la|capra|goat}}), also known under the systematic name '''octanoic acid''' or '''C8 acid''', is a saturated fatty acid, medium-chain fatty acid (MCFA). It has the structural formula {{chem2|H3C\s(CH2)6\sCOOH}}, and is a colorless oily liquid that is minimally soluble in water with a slightly unpleasant rancid-like smell and taste.<ref name=Merck/> Salts and esters of octanoic acid are known as '''octanoates''' or '''caprylates'''. The name of the related acyl group is '''octanoyl''', '''capryloyl''', or '''caprylyl'''.<ref>{{cite web|url=https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:25650|title=CHEBI:25650 - octanoyl group|publisher=Chemical Entities of Biological Interest (ChEBI)|date=23 November 2010|access-date=4 July 2024}}</ref> It is a common industrial chemical, which is produced by oxidation of the C8 aldehyde.<ref name=Ullmann>{{Ullmann|first1=Wilhelm|last1=Riemenschneider|title=Carboxylic Acids, Aliphatic|year=2002|doi=10.1002/14356007.a05_235}}</ref> Its compounds are found naturally in the milk of various mammals and as a minor constituent of coconut oil and palm kernel oil.<ref name="lexicon" />

Two other acids are named after goats via the Latin word ''capra'': caproic acid (C6) and capric acid (C10). Together, these three fatty acids comprise 15% of the fatty acids in goat milk fat.

== Metabolism ==

=== Octanoyl-mtACP === <!-- "Octanoyl-mtACP" and "Octanoyl-ACP" redirect here --> One of the products of the mitochondrial fatty acid synthesis (mtFAS) pathway is octanoic acid bound to the mitochondrial acyl carrier protein (mtACP), also referred to as octanoyl-mtACP.<ref name="Nowinski-2018">{{cite journal | vauthors = Nowinski SM, Van Vranken JG, Dove KK, Rutter J | title = Impact of Mitochondrial Fatty Acid Synthesis on Mitochondrial Biogenesis | journal = Current Biology | volume = 28 | issue = 20 | pages = R1212–R1219 | date = October 2018 | pmid = 30352195 | pmc = 6258005 | doi = 10.1016/j.cub.2018.08.022 | bibcode = 2018CBio...28R1212N }}</ref> In the absence of a mitochondrial acyl-mtACP thioesterase—none has been identified in any animal species—octanoic acid remains attached to mtACP rather than being released as a free fatty acid.<ref>{{Cite journal |last1=Wedan |first1=Riley J. |last2=Longenecker |first2=Jacob Z. |last3=Nowinski |first3=Sara M. |date=2024-01-02 |title=Mitochondrial fatty acid synthesis is an emergent central regulator of mammalian oxidative metabolism |journal=Cell Metabolism |language=English |volume=36 |issue=1 |pages=36–47 |doi=10.1016/j.cmet.2023.11.017 |issn=1550-4131 |pmc=10843818 |pmid=38128528}}</ref> Octanoyl-mtACP serves as the precursor for the biosynthesis of lipoic acid, a vital cofactor required by several key mitochondrial enzymes complexes, including the pyruvate dehydrogenase complex (PDC), the α‑ketoglutarate dehydrogenase complex (OGDC), the 2-oxoadipate dehydrogenase complex (OADHC), the branched‑chain α‑ketoacid dehydrogenase complex (BCKDC), and the glycine cleavage system (GCS).<ref>{{Cite journal |last1=Rowland |first1=Elizabeth A |last2=Snowden |first2=Caroline K |last3=Cristea |first3=Ileana M |date=February 2018 |title=Protein lipoylation: an evolutionarily conserved metabolic regulator of health and disease |journal=Current Opinion in Chemical Biology |language=en |volume=42 |pages=76–85 |doi=10.1016/j.cbpa.2017.11.003 |pmc=5965299 |pmid=29169048}}</ref><ref>{{Cite journal |last1=Solmonson |first1=Ashley |last2=DeBerardinis |first2=Ralph J. |date=May 2018 |title=Lipoic acid metabolism and mitochondrial redox regulation |journal=Journal of Biological Chemistry |volume=293 |issue=20 |pages=7522–7530 |doi=10.1074/jbc.tm117.000259 |doi-access=free |issn=0021-9258|pmc=5961061 }}</ref>

=== Octanoyl-CoA === {{Main|Octanoyl-CoA}} Caprylic acid plays an important role in the body's regulation of energy input and output, a function which is performed by the hormone ghrelin. The sensation of hunger is a signal that the body requires an input of energy in the form of food consumption. Ghrelin stimulates hunger by triggering receptors in the hypothalamus. In order to activate these receptors, ghrelin must undergo a process called acylation in which it acquires an acyl group, and caprylic acid provides this by linking at a specific serine site on ghrelin molecules. Other fatty acids in the same position have similar effects on hunger.{{cn|date=March 2021}}

==Uses==

=== Industrial and commercial use === Caprylic acid is used commercially in the production of esters used in perfumery and also in the manufacture of dyes.{{cn|date=June 2022}}

The acyl chloride of caprylic acid is used in the synthesis of perfluorooctanoic acid.<ref name="savu2000">{{cite encyclopedia |year=2000 |encyclopedia=Kirk-Othmer Encyclopedia of Chemical Technology |page=1 |doi=10.1002/0471238961.0612211519012221.a01 |isbn=978-0-471-23896-6 |chapter=Fluorinated Higher Carboxylic Acids |last1=Savu |first1=Patricia M.}}</ref>

Caprylic acid is an antimicrobial pesticide used as a food contact surface sanitizer in commercial food handling establishments on dairy equipment, food processing equipment, breweries, wineries, and beverage processing plants. It is also used as disinfectant in health care facilities and public places. Caprylic acid is used as an algicide, bactericide, fungicide, and herbicide in nurseries, greenhouses, garden centers, and interiors, and on ornamentation. Products containing caprylic acid are formulated as soluble concentrate/liquids and ready-to-use liquids.<ref>EPA - Antimicrobials Division. [http://www.regulations.gov/#!docketDetail;D=EPA-HQ-OPP-2008-0477 Docket Number; EPA-HQ-OPP-2008-0477 Caprylic (Octanoic) Acid].</ref>

===Dietary uses=== {{see also|Medium-chain triglyceride#Dietary relevance}}

Caprylic acid is taken as a dietary supplement. In the body, caprylic acid would be found as octanoate, or unprotonated caprylic acid.<ref>{{Cite web|url=https://pubchem.ncbi.nlm.nih.gov/compound/379|title=Octanoic acid|last=PubChem|website=pubchem.ncbi.nlm.nih.gov|language=en|access-date=2019-05-15}}</ref>

Some studies have shown that medium-chain triglycerides (MCTs) can help in the process of excess calorie burning, and thus weight loss;<ref>{{cite journal| title = Medium-chain triglycerides|author1=B. Martena |author2=M. Pfeuffer |author3=J. Schrezenmeir |journal= International Dairy Journal |volume= 16| issue= 11|year= 2006| pages =1374–1382 |doi=10.1016/j.idairyj.2006.06.015|pmc=2020023}}</ref><ref>{{Cite journal | last1 = Takeuchi | first1 = H | last2 = Sekine | first2 = S | last3 = Kojima | first3 = K | last4 = Aoyama | first4 = T | title = The application of medium-chain fatty acids: edible oil with a suppressing effect on body fat accumulation | journal = Asia Pacific Journal of Clinical Nutrition | volume = 17 | pages = 320–3 | year = 2008 | issue = Suppl 1 | pmid = 18296368 }}</ref><ref>{{Cite journal | last1 = St-Onge | first1 = MP | last2 = Jones | first2 = PJ | title = Physiological effects of medium-chain triglycerides: potential agents in the prevention of obesity | journal = The Journal of Nutrition | volume = 132 | issue = 3 | pages = 329–32 | year = 2002 | pmid = 11880549 | doi = 10.1093/jn/132.3.329 | doi-access = free }}</ref><ref>{{Cite journal | last1 = Papamandjaris | first1 = AA | last2 = MacDougall | first2 = DE | last3 = Jones | first3 = PJ | title = Medium chain fatty acid metabolism and energy expenditure: obesity treatment implications | journal = Life Sciences | volume = 62 | issue = 14 | pages = 1203–15 | year = 1998 | pmid = 9570335 | doi=10.1016/S0024-3205(97)01143-0 }}</ref><ref name="Clegg">{{Cite journal | last1 = Clegg | first1 = M. E. | title = Medium-chain triglycerides are advantageous in promoting weight loss although not beneficial to exercise performance | journal = International Journal of Food Sciences and Nutrition | volume = 61 | issue = 7 | pages = 653–679 | year = 2010 | pmid = 20367215 | doi = 10.3109/09637481003702114

| s2cid = 6128370 }}</ref> however, a systematic review of the evidence concluded that the overall results are inconclusive.<ref>{{Cite journal | journal = Nutr Hosp | date = 2012 | volume = 27 | issue = 1 | pages = 103–108 | doi= 10.3305/nh.2012.27.1.5369 | title = Influence of the dietary intake of medium chain triglycerides on body composition, energy expenditure and satiety: a systematic review |vauthors=Rego Costa AC, Rosado EL, Soares-Mota M | pmid = 22566308}}</ref> Interest in MCTs has been shown by endurance athletes and the bodybuilding community, but MCTs have not been found to be beneficial to exercise performance.<ref name=Clegg/>

===Medical uses=== Caprylic acid has been studied as part of a ketogenic diet to treat children with intractable epilepsy.<ref name=":0" /> Caprylic acid is being researched as a treatment for essential tremor.<ref name=":0">{{Cite journal|last1=Voller|first1=Bernhard|last2=Lines|first2=Emily|last3=McCrossin|first3=Gayle|last4=Tinaz|first4=Sule|last5=Lungu|first5=Codrin|last6=Grimes|first6=George|last7=Starling|first7=Judith|last8=Potti|first8=Gopal|last9=Buchwald|first9=Peter|date=2016-02-29|title=Dose-escalation study of octanoic acid in patients with essential tremor|journal=Journal of Clinical Investigation|language=en|volume=126|issue=4|pages=1451–1457|doi=10.1172/JCI83621|pmid=26927672|issn=0021-9738|pmc=4811161}}</ref><ref>{{Cite journal|last1=Lowell|first1=Soren Y.|last2=Kelley|first2=Richard T.|last3=Monahan|first3=Marika|last4=Hosbach-Cannon|first4=Carly Jo|last5=Colton|first5=Raymond H.|last6=Mihaila|first6=Dragos|date=2018-12-25|title=The Effect of Octanoic Acid on Essential Voice Tremor: A Double-Blind, Placebo-Controlled Study: Effect of Octanoic Acid on EVT|journal=The Laryngoscope|volume=129|issue=8|pages=1882–1890|language=en|doi=10.1002/lary.27695|pmid=30585335|pmc=6592780}}</ref>

==See also== * List of saturated fatty acids * List of carboxylic acids

==References== {{Reflist}}

== External links ==

* [https://justdoc.com/blog/caprylic-acid-benefits-and-side-effects/ Caprylic Acid Benefits] – Caprylic Acid: Benefits & Side Effects

{{Fatty acids}} {{Authority control}}

{{DEFAULTSORT:Caprylic Acid}} Category:Antifungals Category:Alkanoic acids Category:Biologically based therapies Category:Fatty acids