Palmitic acid[1]
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| Names |
| Preferred IUPAC name
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| Other names
Palmitic acid
C16:0 (Lipid numbers)
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| Identifiers |
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CAS Number
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57-10-3 Y |
| 3D model (Jmol) |
Interactive image |
| ChEMBL |
ChEMBL82293 N |
| ChemSpider |
960 N |
| ECHA InfoCard |
100.000.284 |
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IUPHAR/BPS
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1055 |
| PubChem |
985 |
InChI
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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
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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
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| Properties |
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Chemical formula
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C16H32O2 |
| Molar mass |
256.43 g·mol−1 |
| 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) [8] |
| Boiling point |
351–352 °C (664–666 °F; 624–625 K) [4]
271.5 °C (520.7 °F; 544.6 K)
at 100 mmHg[2]
215 °C (419 °F; 488 K)
at 15 mmHg |
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Solubility in water
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4.6 mg/L (0 °C)
7.19 mg/L (20 °C)
8.26 mg/L (30 °C)
9.9 mg/L (45 °C)
11.8 mg/L (60 °C)[5] |
| Solubility |
soluble in amyl acetate, alcohol, CCl4,[5] 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)[6] |
| Solubility in methyl acetate |
7.81 g/100 g[5] |
| Solubility in ethyl acetate |
10.7 g/100 g[5] |
| Vapor pressure |
0.051 mPa (25 °C)[3]
1.08 kPa (200 °C)
28.06 kPa (300 °C)[7] |
| Acidity (pKa) |
4.75 [3] |
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Magnetic susceptibility (χ)
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-198.6·10−6 cm3/mol |
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Refractive index (nD)
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1.43 (70 °C)[3] |
| Viscosity |
7.8 cP (70 °C)[3] |
| Thermochemistry |
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Specific
heat capacity (C)
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463.36 J/mol·K[7] |
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Std molar
entropy (So298)
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452.37 J/mol·K[7] |
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Std enthalpy of
formation (ΔfHo298)
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-892 kJ/mol[7] |
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Std enthalpy of
combustion (ΔcHo298)
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10030.6 kJ/mol[3] |
| Hazards |
| GHS pictograms |
[2] |
| GHS signal word |
Warning |
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GHS hazard statements
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H319[2] |
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GHS precautionary statements
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P305+351+338[2] |
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EU classification (DSD)
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Xi |
| R-phrases |
R36/37/38 |
| S-phrases |
S26 |
| NFPA 704 |
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| 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).
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| N verify (what is YN ?) |
| Infobox references |
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Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is the most common fatty acid (saturated) found in animals, plants and microorganisms.[9] Its chemical formula is CH3(CH2)14COOH. As its name indicates, it is a major component of the oil from palm trees (palm oil), but can also be found in meats, cheeses, butter, and dairy products. Palmitate is a term for the salts and esters of palmitic acid. The palmitate anion is the observed form of palmitic acid at physiologic pH (7.4).
Aluminium salts of palmitic acid and naphthenic acid were combined during World War II to produce napalm. The word "napalm" is derived from the words naphthenic acid and palmitic acid.
Contents
- 1 Occurrence and production
- 2 Biochemistry
- 3 Applications
- 4 Health effects
- 5 See also
- 6 References
- 7 External links
Occurrence and production
Palmitic acid was discovered by Edmond Frémy in 1840, in saponified palm oil.[10] This remains the primary industrial route for its production, with the triglycerides (fats) in palm oil being hydrolysed by high temperature water (above 200 °C or 390 °F) and the resulting mixture fractionally distilled to give the pure product.[11]
Palmitic acid is naturally produced by a wide range of other plants and organisms, typically at low levels. It is naturally present in butter, cheese, milk, and meat , as well as cocoa butter, soybean oil, and sunflower oil. The cetyl ester of palmitic acid (cetyl palmitate) occurs in spermaceti.
Biochemistry
Excess carbohydrates in the body are converted to palmitic acid. Palmitic acid is the first fatty acid produced during fatty acid synthesis and 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 comprise 21–30% (molar) of human depot fat,[12] and it is a major, but highly variable, lipid component of human breast milk.[13] 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.[14] In biology, some proteins are modified by the addition of a palmitoyl group in a process known as palmitoylation. Palmitoylation is important for membrane localisation of many proteins.
Applications
Palmitic acid is used to produce soaps, cosmetics, and release agents. These applications use sodium palmitate, which is commonly obtained by saponification of palm oil. To this end, palm oil, rendered from palm tree (species Elaeis guineensis), is treated with sodium hydroxide (in the form of caustic soda or lye), which causes hydrolysis of the ester groups. This procedure affords glycerol and sodium palmitate.
Because it is inexpensive and adds texture 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.[15] The aluminium salt is used as a thickening agent of napalm used in military actions.
Hydrogenation of palmitic acid yields cetyl alcohol, which is used to produce detergents and cosmetics.
Recently, a long-acting antipsychotic medication, paliperidone palmitate (marketed as INVEGA Sustenna), used in the treatment of schizophrenia, has been synthesized using the oily palmitate ester as a long-acting release carrier medium when injected intramuscularly. The underlying method of drug delivery is similar to that used with decanoic acid to deliver long-acting depot medication, in particular, neuroleptics such as haloperidol decanoate.
Health effects
According to the World Health Organization, evidence is "convincing" that consumption of palmitic acid increases risk of developing cardiovascular diseases,[16] based on studies indicating that it may increase LDL levels in the blood. Retinyl palmitate is an antioxidant and a source of vitamin A 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, to make vitamin A stable in milk.
Rats fed a diet of 20% palmitic acid and 80% carbohydrate for extended periods showed alterations in central nervous system control of insulin secretion, and suppression of the body's natural appetite-suppressing signals from leptin and insulin (the key hormones involved in weight regulation).[17]
Palmitic acid strongly boosts metastasis in mouse models of human oral cancer cells. Among all fatty acids, it has the strongest effect in boosting the metastatic potential of CD36+ metastasis-initiating cells.[18][19]
See also
- Retinyl palmitate
- Ascorbyl palmitate
References
- ^ Merck Index, 12th Edition, 7128.
- ^ a b c d e f Sigma-Aldrich Co., Palmitic acid. Retrieved on 2014-06-02.
- ^ a b c d e f g CID 985 from PubChem
- ^ Palmitic acid at Inchem.org
- ^ a b c d http://chemister.ru/Database/properties-en.php?dbid=1&id=6488
- ^ Seidell, Atherton; Linke, William F. (1952). [Google Books Solubilities of Inorganic and Organic Compounds] . Van Nostrand. Retrieved 2014-06-02.
- ^ a b c d n-Hexadecanoic acid in Linstrom, P.J.; Mallard, W.G. (eds.) NIST Chemistry WebBook, NIST Standard Reference Database Number 69. National Institute of Standards and Technology, Gaithersburg MD. http://webbook.nist.gov (retrieved 2014-05-11)
- ^ Beare-Rogers, J.; Dieffenbacher, A.; Holm, J.V. (2001). "Lexicon of lipid nutrition (IUPAC Technical Report)". Pure and Applied Chemistry. 73 (4): 685–744. doi:10.1351/pac200173040685.
- ^ Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The Lipid Handbook with Cd-Rom. 3rd ed. Boca Raton: CRC Press, 2007. ISBN 0849396883 | ISBN 978-0849396885
- ^ Frémy, E. (1842). "Memoire sur les produits de la saponification de l'huile de palme". Journal de Pharmacie et de Chimie. XII: 757.
- ^ Anneken, David J.; Both, Sabine; Christoph, Ralf; Fieg, Georg; Steinberner, Udo; Westfechtel, Alfred (2006). "Fatty Acids". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a10_245.pub2.
- ^ Kingsbury, K. J.; Paul, S.; Crossley, A.; Morgan, D. M. (1961). "The fatty acid composition of human depot fat". Biochemical Journal. 78: 541–550. PMC 1205373. PMID 13756126.
- ^ Jensen, RG; Hagerty, MM; McMahon, KE (June 1978). "Lipids of human milk and infant formulas: a review". Am. J. Clin. Nutr. 31: 990–1016. PMID 352132.
- ^ Fatty acid biosynthesis - Reference pathway
- ^ US Soil Association standard 50.5.3
- ^ 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 10)
- ^ Benoit SC, Kemp CJ, Elias CF, Abplanalp W, Herman JP, Migrenne S, Lefevre AL, Cruciani-Guglielmacci C, Magnan C, Yu F, Niswender K, Irani BG, Holland WL, Clegg DJ (2009). "Palmitic acid mediates hypothalamic insulin resistance by altering PKC-θ subcellular localization in rodents". Journal of Clinical Investigation. 119 (9): 2577–2587. doi:10.1172/JCI36714. PMC 2735917. PMID 19726875.
- ^ Pascual, Gloria; et al. (7 December 2016). "Targeting metastasis-initiating cells through the fatty acid receptor CD36". Nature. doi:10.1038/nature20791. Retrieved 7 December 2016.
- ^ Sánchez, Lucas (7 December 2016). "Descubiertas las células que inician la metástasis del cáncer" (in Spanish). El País. Retrieved 7 December 2016.
External links
Media related to Palmitic acid at Wikimedia Commons
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Lipids: fatty acids
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| Saturated |
- Butyric (C4)
- Valeric (C5)
- Caproic (C6)
- Enanthic (C7)
- Caprylic (C8)
- Pelargonic (C9)
- Capric (C10)
- Undecylic (C11)
- Lauric (C12)
- Tridecylic (C13)
- Myristic (C14)
- Pentadecanoic (C15)
- Palmitic (C16)
- Margaric (C17)
- Stearic (C18)
- Nonadecylic (C19)
- Arachidic (C20)
- Heneicosylic (C21)
- Behenic (C22)
- Tricosylic (C23)
- Lignoceric (C24)
- Pentacosylic (C25)
- Cerotic (C26)
- Heptacosylic (C27)
- Montanic (C28)
- Nonacosylic (C29)
- Melissic (C30)
- Hentriacontylic (C31)
- Lacceroic (C32)
- Psyllic (C33)
- Geddic (C34)
- Ceroplastic (C35)
- Hexatriacontylic (C36)
- Heptatriacontanoic (C37)
- Octatriacontanoic (C38)
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| ω−3 Unsaturated |
- α-Linolenic (18:3)
- Stearidonic (18:4)
- Eicosapentaenoic (20:5)
- Docosahexaenoic (22:6)
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| ω−6 Unsaturated |
- Linoleic (18:2)
- γ-Linolenic (18:3)
- Dihomo-γ-linolenic (20:3)
- Arachidonic (20:4)
- Adrenic (22:4)
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| ω−7 Unsaturated |
- Palmitoleic (16:1)
- Vaccenic (18:1)
- Paullinic (20:1)
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| ω−9 Unsaturated |
- Oleic (18:1)
- Elaidic (trans-18:1)
- Gondoic (20:1)
- Erucic (22:1)
- Nervonic (24:1)
- Mead (20:3)
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Palm oil
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| Oil palms |
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Diseases and
pests |
- Bagworm moth
- Basal stem rot (Ganoderma orbiforme)
- Cadang-cadang disease
- Little leaf syndrome
- Oryctes rhinoceros
- Rhynchophorus palmarum
- Oil palm bunch moth
- Tirathaba mundella
- Tirathaba rufivena
- Red ring disease (Bursaphelenchus cocophilus)
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| Components |
- Mesocarp
- Palm kernel
- Palm oil
- stearin
- stearic acid
- linoleic acid
- myristic acid
- oleic acid
- palmitic acid
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| Processes |
- Fractionation
- Hydrolysis
- Milling
- Refining
- Saponification
- Transesterification
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| Products |
- Biodiesel
- Bioplastics
- Cellulosic ethanol
- Girl Scout Cookies
- Oleochemicals
- Vegetable oil
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| Organisations |
| Producers |
- Bumitama Agri
- Cargill
- Equatorial Palm Oil
- Federal Global Ventures (FGV)
- Feronia Inc.
- IOI Group
- Kuala Lumpur Kepong Berhad
- Sime Darby
- Wilmar International
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| Buyers/ processors |
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Governmental/
non-governmental |
- FELDA
- The Forest Trust
- Indonesia Commodity and Derivatives Exchange
- Malaysia Derivatives Exchange
- Malaysian Palm Oil Board
- Roundtable on Sustainable Palm Oil
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Policies, impacts
and debates |
- Biodiesel impacts
- Biofuel policy (Malaysia)
- Biofuels issues
- Certified sustainable palm oil
- Deforestation
- Food vs. fuel
- Social and environmental impacts
- Vegetable oils as alternative energy
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- Indonesia
- Malaysia
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