Palmitic acid
542488
209447813
2008-05-01T13:07:09Z
81.172.122.195
{{Chembox new
|Reference=<ref>''[[Merck Index]]'', 12th Edition, '''7128'''.</ref>
|ImageFile=Palmitic acid structure.png
|ImageSize=350px
|IUPACName=hexadecanoic acid
|Section1= {{Chembox Identifiers
| CASNo=57-10-3
| PubChem=985
| SMILES=CCCCCCCCCCCCCCCC(=O)O
}}
|Section2= {{Chembox Properties
| Formula=C<sub>16</sub>H<sub>32</sub>O<sub>2</sub>
| MolarMass=256.42 g/mol
| Appearance=White crystals
| Density=0.853 g/cm<sup>3</sup> at 62 °C
| MeltingPt=63-64 °C
| BoilingPt=351-352 °C<ref>[http://www.inchem.org/documents/icsc/icsc/eics0530.htm Palmitic acid] at Inchem.org</ref><br>215 °C at 15 mmHg
| Solubility=Insoluble
}}
|Section3= {{Chembox Hazards
| MainHazards=
| FlashPt=
| Autoignition=
}}
}}
'''Palmitic acid''', or hexadecanoic acid in [[IUPAC nomenclature]], is one of the most common saturated [[fatty acid]]s found in animals and plants. As its name indicates, it is a major component of the oil from [[palm tree]]s ([[palm oil]] and palm kernel oil). The word palmitic is from the French "palmitique", the [[pith]] of the palm tree. Palmitic acid was discovered by [[Edmond Frémy]] in 1840, in [[Saponification|saponified]] palm oil.<ref>E. Frémy, Memoire sur les produits de la saponification de l’huile de palme, Journal de Pharmacie et de Chimie XII (1842), p. 757.</ref> [[Butter]], [[cheese]], [[milk]] and [[meat]] also contain this fatty acid. <ref>[http://www.westonaprice.org/knowyourfats/import_sat_fat.html The Importance of Saturated Fats for Biological Functions] by Mary Enig, PhD. Wise Traditions in Food, Farming and the Healing Arts (the quarterly magazine of the Weston A. Price Foundation). Spring 2004.</ref>
'''Palmitate''' is a term for the salts or [[ester]]s of palmitic acid. The palmitate anion is the observed form of palmitic acid at physiological pH. {{Fact|date=July 2007}}
==Biochemistry==
Palmitic acid is the first fatty acid produced during [[lipogenesis]] (fatty acid synthesis) and from which longer fatty acids can be produced. Palmitate negatively feeds back on [[acetyl-CoA carboxylase]] (ACC) which is responsible for converting acetyl-ACP to malonyl-ACP on the growing acyl chain, thus preventing further palmitate generation. <ref>[http://www.genome.jp/kegg/pathway/map/map00061.html Fatty acid biosynthesis - Reference pathway]</ref>
Reduction of palmitic acid yields [[cetyl alcohol]].
==Uses==
Retinyl palmitate is an [[antioxidant]] and a [[vitamin A]] compound added to low-fat milk to replace the vitamin content lost through the removal of milk fat. Palmitate is attached to the alcohol form of vitamin A, [[retinol]], in order to make vitamin A stable in milk. {{Fact|date=July 2007}}
Derivatives of palmitic acid were used in combination with [[naphtha]] during [[World War II]] to produce [[napalm]] ('''''na'''''phthenic and '''''palm'''''itic acids). <ref name="GS Napalm">[http://www.globalsecurity.org/military/systems/munitions/napalm.htm Napalm<!-- Bot generated title -->]</ref>
The [[WHO]] claims there is convincing evidence that dietary intake of palmitic acid increases risk of developing cardiovascular diseases. <ref>[http://www.who.int/hpr/NPH/docs/who_fao_expert_report.pdf DIET, NUTRITION AND THE PREVENTION OF CHRONIC DISEASES], WHO Technical Report Series 916, Report of a Joint WHO/FAO Expert Consultation, [[World Health Organization]], Geneva, 2003, p. 88 (Table)</ref> However, possibly less-disinterested studies have shown no ill effect, or even a favorable effect, of dietary consumption of palmitic acid on blood lipids and cardiovascular disease, so that the [[WHO]] finding may be deemed controversial.<ref>[[Palm oil#Blood cholesterol controversy|Palm oil and blood cholesterol controversy]], Wikipedia</ref> However, another study showed that palmitic acid has no hypercholesterolaemic effect if intake of linoleic acid is greater than 4.5% of energy. On the other hand, it was shown that, if the diet contains trans fatty acids, the health effects are negative, causing an LDL cholesterol increase and HDL cholesterol decrease. <ref>{{cite journal |author=French MA, Sundram K, Clandinin MT |title=Cholesterolaemic effect of palmitic acid in relation to other dietary fatty acids |journal=Asia Pacific journal of clinical nutrition |volume=11 Suppl 7 |issue= |pages=S401–7 |year=2002 |pmid=12492626 |doi=}}</ref>
==References==
{{Reflist}}
{{Fatty acids}}
[[Category:Fatty acids]]
[[Category:Palmitates]]
[[bg:Палмитинова киселина]]
[[ca:Àcid palmític]]
[[cs:Kyselina palmitová]]
[[de:Palmitinsäure]]
[[es:Ácido palmítico]]
[[eo:Palmita acido]]
[[fr:Acide palmitique]]
[[id:Asam palmitat]]
[[it:Acido palmitico]]
[[lv:Palmitīnskābe]]
[[nl:Palmitinezuur]]
[[ja:パルミチン酸]]
[[no:Palmitinsyre]]
[[pl:Kwas palmitynowy]]
[[pt:Ácido palmítico]]
[[ru:Пальмитиновая кислота]]
[[sk:Kyselina palmitová]]
[[fi:Palmitiinihappo]]
[[sv:Palmitinsyra]]
[[tr:Palmitik asit]]
[[zh:棕櫚酸]]