Phytanic acid

Structural formula
	; ;
	Naturally occurring stereoisomers of phytanic acid: ; (all- R ) form (top) and (3 S , 7 R , 11 R ) form (bottom)
General
Surname	Phytanic acid
other names	(7 R , 11 R ) -3,7,11,15-tetramethylhexadecanoic acid ( IUPAC )
Molecular formula	C 20 H 40 O 2
External identifiers / databases
EC number	630-841-4
ECHA InfoCard	100.159.135
PubChem	26840
Wikidata	Q421171
properties
Molar mass	312.54 g mol −1
Physical state	liquid
Melting point	−7 ° C [(all- R ) form]
boiling point	221 ° C [1000 Pa ; (all- R ) form]; 174 ° C [26.65 Pa ; (3 S , 7 R , 11 R ) shape];
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 315-319-335
	P: 261-305 + 351 + 338
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Phytanic acid is a naturally occurring minor fatty acid from the group of alkanoic acids . It is a long-chain, methyl- branched, saturated fatty acid . It has a di terpenoid structure and is an isoprene lipid , it is an isomer of arachidic acid .

Occurrence

It arises in ruminants as a breakdown product of chlorophyll and is ingested by humans with the consumption of meat and dairy products . But it is also found in animal fats , fish and seafood. A (rare) metabolic disorder in people who cannot break down phytanic acid is Refsum's syndrome . The average value in the blood plasma is around 1–2 mg / l.

biology

Humans do not synthesize phytanic acid, but ingest phytanic acid in their diet. Phytanic acid is broken down in the peroxisomes of the cells by means of α-oxidation . Since the acid has a methyl group on its third carbon atom (Cβ), β-oxidation is not possible. The pristanic acid is metabolized by the α-oxidation ; it can now be broken down further by the β-oxidation.

Phytanic acid acts as a PPAR - receptor agonist and therefore is in the position in the glucose metabolism intervene. Phytanic acid formed from plant chlorophyll has several methyl side chains. For this reason, 3C propionyl-CoA, as well as three 2C acetyl-CoA and one isobutyryl-CoA are formed during degradation.

use

Since grass-eating cows have more phytanic acid in their milk, it is possible to make a statement about the phytanic acid content of dairy products and thus distinguish products from animals that are fed green or grazed from others. The composition of the milk therefore changes accordingly, even with products from organic cultivation with appropriate feeding.

Analytics

Small amounts of phytanic acid can be detected with gas chromatography .

Web links

Wikibooks: Biochemistry and Pathobiochemistry: Breakdown of Branched Chain Fatty Acids - Learning and Teaching Materials

Individual evidence

↑ ^a ^b ^c ^d Entry on phytanic acid. In: Römpp Online . Georg Thieme Verlag, accessed on January 2, 2015.
↑ ^a ^b Data sheet Phytanic acid, ≥96%, mixture of isomers from Sigma-Aldrich , accessed on August 8, 2017 ( PDF ).
↑ Wolfgang Robert Reininger: Phytanic acid, an almost overlooked branched-chain fatty acid in human nutrition. Diploma thesis, Univ. Vienna, 2012, online (PDF; 792 kB).
↑ JH Baxter: Absorption of chlorophyll phytol in normal man and in patients with Refsum's disease . In: J. Lipid Res . 9, No. 5, 1968, pp. 636-641. PMID 4177872 .
↑ M. Heim M, J. Johnson et al .: Phytanic acid, a natural peroxisome proliferator-activated receptor (PPAR) agonist, regulates glucose metabolism in rat primary hepatocytes . (PDF): FASEB J . 16, No. 7, 2002, pp. 718-720. doi : 10.1096 / fj.01-0816fje . PMID 11923221 .
^ W. Vetter, M. Schröder: Concentrations of phytanic acid and pristanic acid are higher in organic than in conventional dairy products from the German market . In: Food Chem . 119, No. 2, 2009, pp. 746-752. doi : 10.1016 / j.foodchem.2009.07.027 .

[RÖMPP4-1] Entry on phytanic acid. In: Römpp Online . Georg Thieme Verlag, accessed on January 2, 2015.

[Sigma-2] Data sheet Phytanic acid, ≥96%, mixture of isomers from Sigma-Aldrich , accessed on August 8, 2017 ( PDF ).

[3] Wolfgang Robert Reininger: Phytanic acid, an almost overlooked branched-chain fatty acid in human nutrition. Diploma thesis, Univ. Vienna, 2012, online (PDF; 792 kB).

[4] JH Baxter: Absorption of chlorophyll phytol in normal man and in patients with Refsum's disease . In: J. Lipid Res . 9, No. 5, 1968, pp. 636-641. PMID 4177872 .

[5] M. Heim M, J. Johnson et al .: Phytanic acid, a natural peroxisome proliferator-activated receptor (PPAR) agonist, regulates glucose metabolism in rat primary hepatocytes . (PDF): FASEB J . 16, No. 7, 2002, pp. 718-720. doi : 10.1096 / fj.01-0816fje . PMID 11923221 .

[6] W. Vetter, M. Schröder: Concentrations of phytanic acid and pristanic acid are higher in organic than in conventional dairy products from the German market . In: Food Chem . 119, No. 2, 2009, pp. 746-752. doi : 10.1016 / j.foodchem.2009.07.027 .