Palmitic acid

From Wikipedia, the free encyclopedia
(Redirected from Palmitic)
Jump to navigation Jump to search
Palmitic acid[1]
File:Palmitic acid.svg
File:Palmitic-acid-3D-balls.png
File:Kyselina palmitová.jpg
Names
Preferred IUPAC name
Hexadecanoic acid
Other names
Palmitic acid
C16:0 (Lipid numbers)
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard Lua error in Module:Wikidata at line 880: attempt to index field 'wikibase' (a nil value). Lua error in Module:Wikidata at line 880: attempt to index field 'wikibase' (a nil value).Lua error in Module:EditAtWikidata at line 29: attempt to index field 'wikibase' (a nil value).
E number Lua error in Module:Wikidata at line 880: attempt to index field 'wikibase' (a nil value).
UNII
  • {{#property:P3117}}Lua error in Module:EditAtWikidata at line 29: attempt to index field 'wikibase' (a nil value).
  • InChI=1S/C16H32O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16(17)18/h2-15H2,1H3,(H,17,18) ☒N
    Key: IPCSVZSSVZVIGE-UHFFFAOYSA-N ☒N
  • InChI=1/C16H32O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16(17)18/h2-15H2,1H3,(H,17,18)
    Key: IPCSVZSSVZVIGE-UHFFFAOYAJ
  • CCCCCCCCCCCCCCCC(=O)O
Properties
C16H32O2
Molar mass 256.430 g/mol
Appearance White crystals
Density 0.852 g/cm3 (25 °C)[2]
0.8527 g/cm3 (62 °C)[3]
Melting point 62.9 °C (145.2 °F; 336.0 K)[7]
Boiling point 351–352 °C (664–666 °F; 624–625 K)[8]
271.5 °C (520.7 °F; 544.6 K), 100 mmHg[2]
215 °C (419 °F; 488 K), 15 mmHg
4.6 mg/L (0 °C)
7.2 mg/L (20 °C)
8.3 mg/L (30 °C)
10 mg/L (45 °C)
12 mg/L (60 °C)[4]
Solubility Soluble in amyl acetate, alcohol, CCl4,[4] C6H6
Very soluble in CHCl3[3]
Solubility in ethanol 2 g/100 mL (0 °C)
2.8 g/100 mL (10 °C)
9.2 g/100 mL (20 °C)
31.9 g/100 mL (40 °C)[5]
Solubility in methyl acetate 7.81 g/100 g[4]
Solubility in ethyl acetate 10.7 g/100 g[4]
Vapor pressure 0.051 mPa (25 °C)[3]
1.08 kPa (200 °C)
28.06 kPa (300 °C)[6]
Acidity (pKa) 4.75 [3]
−198.6·10−6 cm3/mol
1.43 (70 °C)[3]
Viscosity 7.8 cP (70 °C)[3]
Thermochemistry
463.36 J/(mol·K)[6]
452.37 J/(mol·K)[6]
−892 kJ/mol[6]
10030.6 kJ/mol[3]
Hazards
GHS labelling:
GHS07: Exclamation mark[2]
Warning
H319[2]
P305+P351+P338[2]
NFPA 704 (fire diamond)

Error: Image is invalid or non-existent.

1
1
0
Flash point 206 °C (403 °F; 479 K)[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.[9][10] Its chemical formula is CH3(CH2)14COOH, and its C:D ratio (the total number of carbon atoms to the number of carbon-carbon double bonds) is 16:0. It is a major component of palm oil from the fruit of Elaeis guineensis (oil palms), making up to 44% of total fats. Meats, cheeses, butter, and other dairy products also contain palmitic acid, amounting to 50–60% of total fats.[11]

Palmitates are the salts and esters of palmitic acid. The palmitate anion is the observed form of palmitic acid at physiologic pH (7.4). Major sources of C16:0 are palm oil, palm kernel oil, coconut oil, and milk fat.[12]

Dietary palmitic acid intake is associated with an increased cardiovascular disease risk through raising low-density lipoprotein.[13]

Occurrence and production

[edit | edit source]

Palmitic acid was discovered by saponification of palm oil, which process remains today the primary industrial route for producing the acid.[14] Triglycerides (fats) in palm oil are hydrolysed by high-temperature water and the resulting mixture is fractionally distilled.[15]

Dietary sources

[edit | edit source]

Palmitic acid is produced by a wide range of plants and organisms, typically at low levels. Among common foods it is present in milk, butter, cheese, and some meats, as well as cocoa butter, olive oil, soybean oil, and sunflower oil, (see table).[16] Karukas contain 44.90% palmitic acid.[17] The cetyl ester of palmitic acid, cetyl palmitate, occurs in spermaceti.

Palmitic acid content of common foods
Food % of total calories
Palm oil 45.1%
Beef tallow 26.5%
Butter fat 26.2%
Cocoa butter 25.8%
Lard 24.8%
Cottonseed oil 24.7%
Chicken 23.2%
Corn oil 12.2%
Peanut oil 11.6%
Soybean oil 11%
Coconut oil 8.4%
Palm kernel oil 8%
Rapeseed oil 3.6%
Source:[18]

Biochemistry

[edit | edit source]

Palmitic acid is the first fatty acid produced during fatty acid synthesis and is the precursor to longer fatty acids. As a consequence, palmitic acid is a major body component of animals. In humans, one analysis found it to make up 21–30% (molar) of human depot fat,[19] and it is a major, but highly variable, lipid component of human breast milk.[20] Palmitic acid comprises nearly half of total human brain saturated fatty acids.[21]

Palmitate negatively feeds back on acetyl-CoA carboxylase (ACC), which is responsible for converting acetyl-CoA to malonyl-CoA, which in turn is used to add to the growing acyl chain, thus preventing further palmitate generation.[22] Some proteins are modified by the addition of a palmitoyl group in a process known as palmitoylation. Palmitoylation is important for localisation of many membrane proteins.

Applications

[edit | edit source]

Surfactant

[edit | edit source]

Palmitic acid is used to produce soaps, cosmetics, and industrial mold release agents. These applications use sodium palmitate, which is commonly obtained by saponification of palm oil. To this end, palm oil, rendered from palm trees (species Elaeis guineensis), is treated with sodium hydroxide (in the form of caustic soda or lye), which causes hydrolysis of the ester groups, yielding glycerol and sodium palmitate.

Foods

[edit | edit source]

Because it is inexpensive and adds texture and "mouthfeel" to processed foods (convenience food), palmitic acid and its sodium salt find wide use in foodstuffs. Sodium palmitate is permitted as a natural additive in organic products.[23]

Military

[edit | edit source]

Aluminium salts of palmitic acid and naphthenic acid were the gelling agents used with volatile petrochemicals during World War II to produce napalm. The word "napalm" is derived from the words naphthenic acid and palmitic acid.[24]

Research

[edit | edit source]

It is well accepted in the medical community that palmitic acid from dietary sources raises low-density lipoprotein (LDL) and total cholesterol.[18][25][26][27] The World Health Organization have stated there is convincing evidence that palmitic acid increases cardiovascular disease risk.[28] Palmitic acid intake is associated with an increased cancer risk, including prostate cancer.[29][30]

A 2021 review indicated that replacing dietary palmitic acid and other saturated fatty acids with unsaturated fatty acids, such as oleic acid, could reduce several biomarkers of cardiovascular and metabolic diseases.[31]

See also

[edit | edit source]

References

[edit | edit source]
  1. ^ Merck Index, 12th Edition, 7128.
  2. ^ a b c d e f Sigma-Aldrich Co., Palmitic acid. Retrieved on 2014-06-02.
  3. ^ a b c d e f g CID 985 from PubChemLua error in Module:WikidataCheck at line 29: attempt to index field 'wikibase' (a nil value).
  4. ^ a b c d Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  5. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  6. ^ a b c d n-Hexadecanoic acid in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD) (retrieved 2014-05-11)
  7. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  8. ^ Palmitic acid at Inchem.org
  9. ^ Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The Lipid Handbook, 3rd ed. Boca Raton: CRC Press, 2007. Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). | Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  10. ^ The most common fatty acid is the monounsaturated oleic acid. See: https://pubchem.ncbi.nlm.nih.gov/compound/965#section=Top
  11. ^ Lua error in Module:Cite_Q/config at line 10: attempt to index field 'wikibase' (a nil value).
  12. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  13. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  14. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  15. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  16. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  17. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  18. ^ a b Nelson, Gary J. (1991). Health Effects of Dietary Fatty Acids. American Oil Chemists' Society. pp. 84-86. Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  19. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  20. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  21. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  22. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Pathway Map 00061
  23. ^ US Soil Association standard 50.5.3
  24. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  25. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  26. ^ Mensink, Ronald P. (2016). "Effects of saturated fatty acids on serum lipids and lipoproteins: a systematic review and regression analysis". World Health Organization. Retrieved 14 March 2023.
  27. ^ Rao, Gundu HR. (2020). Clinical Handbook of Coronary Artery Disease. Jaypee Brothers Medical Publishers. pp. 186-187. Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  28. ^ "Diet, Nutrition and the Prevention of Chronic Diseases". World Health Organization. p. 82. Retrieved 16 March 2023.
  29. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  30. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  31. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
[edit | edit source]
  • Error creating thumbnail: File missing Media related to Lua error in Module:Commons_link at line 62: attempt to index field 'wikibase' (a nil value). at Wikimedia Commons
  • Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).

Lua error in Module:Authority_control at line 153: attempt to index field 'wikibase' (a nil value).

Retrieved from "http://70.231.62.181/index.php?title=Palmitic_acid&oldid=1148600"