{{Chembox <!-- Images --> | Name = Taxoleic acid | ImageFile = Taxoleic acid.png | ImageSize = 250px | ImageAlt = <!-- Names --> | IUPACName = (5''Z'',9''Z'')-octadeca-5,9-dienoic acid | OtherNames = | Section1 = {{Chembox Identifiers | CASNo = | CASNo_Ref = {{Cascite|changed|CAS}} | ChemSpiderID = 4471901 | DTXSID = | EC_number = | ChEBI = 165493 | ChEMBL = | KEGG = | UNII = | PubChem = 5312476 | InChI = InChI=1S/C18H32O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20/h9-10,13-14H,2-8,11-12,15-17H2,1H3,(H,19,20)/b10-9-,14-13- | InChIKey = DFJAXEWDHVOILU-KWUOUXIESA-N | SMILES = CCCCCCCC/C=C\CC/C=C\CCCC(=O)O }} | Section2 = {{Chembox Properties | H=32|O=2|C=18 | MolarMass = | Appearance = | Density = | MeltingPtC = | BoilingPtC = | BoilingPt_ref = | Solubility = }} | Section3 = {{Chembox Hazards | GHSPictograms = | GHSSignalWord = | GHS_ref = | HPhrases = | PPhrases = | MainHazards = | FlashPt = | AutoignitionPt = }} }} '''Taxoleic acid''' is a diunsaturated fatty acid composed of 18 carbon atoms with double bonds in the positions 5=6 and 9=10, both in ''cis''-configuration.<ref>{{cite book |last1=Leray |first1=Claude |title=Introduction to Lipidomics: From Bacteria to Man |date=19 September 2012 |publisher=CRC Press |isbn=978-1-4665-5147-3 |page=27 |url=https://books.google.com/books?id=plXOBQAAQBAJ&dq=Taxoleic+acid&pg=PA27 |access-date=18 May 2025 |language=en}}</ref><ref>{{cite book |last1=Alasalvar |first1=Cesarettin |last2=Shahidi |first2=Fereidoon |title=Tree Nuts: Composition, Phytochemicals, and Health Effects |date=17 December 2008 |publisher=CRC Press |isbn=978-1-4200-1939-1 |page=287 |url=https://books.google.com/books?id=Uu4nzKx74noC&dq=Taxoleic+acid&pg=PA287 |access-date=18 May 2025 |language=en}}</ref> Taxoleic acid is isomeric to linoleic acid.
==Natural occurrence== The acid is present in the seed oils of conifers, such as ''Pinus nigra''<ref>{{cite journal |last1=Bagci |first1=Eyup |title=Fatty acids and tocochromanol patterns of some Turkish Apiaceae (Umbelliferae) plants; a chemotaxonomic approach |journal=Acta Botanica Gallica |date=1 January 2007 |volume=154 |issue=2 |pages=143–151 |doi=10.1080/12538078.2007.10516050 |bibcode=2007AcBG..154..143B |url=https://www.tandfonline.com/doi/abs/10.1080/12538078.2007.10516050 |access-date=18 May 2025 |issn=1253-8078|url-access=subscription }}</ref> (≈47%), ''Taxus cuspidata''<ref>{{cite journal |last1=Takagi |first1=Toru |last2=Itabashi |first2=Yutaka |title=cis-5-olefinic unusual fatty acids in seed lipids of gymnospermae and their distribution in triacylglycerols |journal=Lipids |date=1982 |volume=17 |issue=10 |pages=716–723 |doi=10.1007/BF02534657 |url=https://aocs.onlinelibrary.wiley.com/doi/10.1007/BF02534657 |access-date=18 May 2025 |language=en |issn=1558-9307|url-access=subscription }}</ref> (≈16.2%), ''Taxus baccata''<ref>{{cite journal |last1=Madrigal |first1=R. V. |last2=Smith Jr. |first2=C. R. |title=Taxus baccata seed oil: A new source ofcis-5,cis-9-octadecadienoic acid |journal=Lipids |date=1975 |volume=10 |issue=8 |pages=502–504 |doi=10.1007/BF02532438 |pmid=1160526 |url=https://aocs.onlinelibrary.wiley.com/doi/10.1007/BF02532438 |access-date=18 May 2025 |language=en |issn=1558-9307|url-access=subscription }}</ref> (≈12.2%), ''Cedrus libani'' (≈9.4%), ''Abies pinsapo'' (≈8.2%), ''Pinus pinaster'' (≈7.1%), ''Abies alba'' (≈6.2%), among others.<ref>{{cite journal |last1=Wolff |first1=R. L. |last2=Deluc |first2=Laurent G. |last3=Marpeau |first3=Anne M. |last4=Comps |first4=Bernard |title=Chemotaxonomic differentiation of conifer families and genera based on the seed oil fatty acid compositions: multivariate analyses |journal=Trees |date=1 December 1997 |volume=12 |issue=2 |pages=57–65 |doi=10.1007/s004680050122 |bibcode=1997Trees..12...57W |url=https://link.springer.com/article/10.1007/s004680050122 |access-date=18 May 2025 |language=en |issn=1432-2285|url-access=subscription }}</ref><ref>{{cite journal |last1=Wolff |first1=Robert L. |last2=Deluc |first2=Laurent G. |last3=Marpeau |first3=Anne M. |title=Conifer seeds: Oil content and fatty acid composition |journal=Journal of the American Oil Chemists' Society |date=1996 |volume=73 |issue=6 |pages=765–771 |doi=10.1007/BF02517953 |url=https://aocs.onlinelibrary.wiley.com/doi/10.1007/BF02517953 |access-date=18 May 2025 |language=en |issn=1558-9331|url-access=subscription }}</ref>
It is found in conifers, along with other fatty acids (juniperonic, pinolenic, coniferonic, sciadonic acid) that have a double bond in the position 5, separated by more than one methylene group from the next double bond.<ref>{{cite journal |last1=Pédrono |first1=Frédérique |last2=Boulier-Monthéan |first2=Nathalie |last3=Boissel |first3=Françoise |last4=Ossemond |first4=Jordane |last5=Viel |first5=Roselyne |last6=Fautrel |first6=Alain |last7=Marchix |first7=Justine |last8=Dupont |first8=Didier |title=Sciadonic acid derived from pine nuts as a food component to reduce plasma triglycerides by inhibiting the rat hepatic Δ9-desaturase |journal=Scientific Reports |date=10 April 2020 |volume=10 |issue=1 |pages=6223 |doi=10.1038/s41598-020-63301-3 |url=https://www.nature.com/articles/s41598-020-63301-3 |access-date=19 May 2025 |language=en |issn=2045-2322|pmc=7148351 }}</ref>
==Biosynthesis== Taxoleic acid is believed to be biosynthesized from oleic acid by the enzyme Δ5-desaturase.<ref>{{cite book |last1=Rahman |first1=Atta-ur |title=Studies in Natural Products Chemistry |date=23 June 2008 |publisher=Elsevier |isbn=978-0-08-056983-3 |page=353 |url=https://books.google.com/books?id=-M6NmLeGVD4C&dq=Taxoleic+acid&pg=PA353 |access-date=18 May 2025 |language=en}}</ref> A similar enzyme capable of producing taxolenic acid was also isolated from the oomycete ''Pythium irregulare''.<ref>{{cite journal |last1=Hong |first1=Haiping |last2=Datla |first2=Nagamani |last3=Mackenzie |first3=Samuel L. |last4=Qiu |first4=Xiao |title=Isolation and characterization of a Δ5 FA desaturase from Pythium irregulare by heterologous expression in Saccharomyces cerevisiae and oilseed crops |journal=Lipids |date=2002 |volume=37 |issue=9 |pages=863–868 |doi=10.1007/s11745-002-0972-5 |pmid=12458621 |url=https://aocs.onlinelibrary.wiley.com/doi/10.1007/s11745-002-0972-5 |access-date=18 May 2025 |language=en |issn=1558-9307}}</ref>
The biosynthesis of taxolenic acid and similar fatty acids has also been studied in sponges, where the double bonds are introduced sequentially in a random order.<ref>{{cite journal |last1=Carballeira |first1=Néstor M. |last2=Medina |first2=Jesús R. |title=New Δ5,9 Fatty Acids in the Phospholipids of the Sea Anemone Stoichactis helianthus |journal=Journal of Natural Products |date=1 December 1994 |volume=57 |issue=12 |pages=1688–1695 |doi=10.1021/np50114a011 |pmid=7714536 |bibcode=1994JNAtP..57.1688C |url=https://pubs.acs.org/doi/abs/10.1021/np50114a011 |access-date=18 May 2025 |issn=0163-3864|url-access=subscription }}</ref>
== References == <references/>
Category:Alkenoic acids Category:Fatty acids