Pristanic acid
Encyclopedia
Pristanic acid is a terpenoid
Terpenoid
The terpenoids , sometimes called isoprenoids, are a large and diverse class of naturally occurring organic chemicals similar to terpenes, derived from five-carbon isoprene units assembled and modified in thousands of ways. Most are multicyclic structures that differ from one another not only in...

 acid
Acid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...

 present at micromolar concentrations in the blood plasma
Blood plasma
Blood plasma is the straw-colored liquid component of blood in which the blood cells in whole blood are normally suspended. It makes up about 55% of the total blood volume. It is the intravascular fluid part of extracellular fluid...

 of healthy individuals. It is also found in the lipids from many sources such as freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...

 sponges, krill
Krill
Krill is the common name given to the order Euphausiacea of shrimp-like marine crustaceans. Also known as euphausiids, these small invertebrates are found in all oceans of the world...

, earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...

s, whale
Whale
Whale is the common name for various marine mammals of the order Cetacea. The term whale sometimes refers to all cetaceans, but more often it excludes dolphins and porpoises, which belong to suborder Odontoceti . This suborder also includes the sperm whale, killer whale, pilot whale, and beluga...

s, human milk fat, bovine depot fat, butterfat or California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

n petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...

. It is usually present in combination with phytanic acid
Phytanic acid
Phytanic acid is a branched chain fatty acid that humans can obtain through the consumption of dairy products, ruminant animal fats, and certain fish. Western diets are estimated to provide 50-100 mg of phytanic acid per day...

. In humans, pristanic acid is obtained from two sources: either directly from the diet or as the alpha oxidation
Alpha oxidation
Enzymatic steps of alpha oxidation|right|thumb|250pxAlpha oxidation is a process by which certain fatty acids are broken down by removal of a single carbon from the carboxyl end...

 product of phytanic acid
Phytanic acid
Phytanic acid is a branched chain fatty acid that humans can obtain through the consumption of dairy products, ruminant animal fats, and certain fish. Western diets are estimated to provide 50-100 mg of phytanic acid per day...

. At physiological concentrations pristanic acid is a natural ligand for PPARα. In liver, pristanic acid is degraded by peroxisomal
Peroxisome
Peroxisomes are organelles found in virtually all eukaryotic cells. They are involved in the catabolism of very long chain fatty acids, branched chain fatty acids, D-amino acids, polyamines, and biosynthesis of plasmalogens, etherphospholipids critical for the normal function of mammalian brains...

 beta oxidation
Beta oxidation
Beta oxidation is the process by which fatty acids, in the form of Acyl-CoA molecules, are broken down in mitochondria and/or in peroxisomes to generate Acetyl-CoA, the entry molecule for the Citric Acid cycle....

 to propionyl-CoA. Together with phytanic acid, pristanic acid accumulates in several inherited disorders such as Zellweger syndrome
Zellweger syndrome
Zellweger syndrome, also called cerebrohepatorenal syndrome is a rare, congenital disorder, characterized by the reduction or absence of functional peroxisomes in the cells of an individual. It is one of a family of disorders called leukodystrophies...

.

Pristanic acid was first isolated from butterfat
Butterfat
Butterfat or milkfat is the fatty portion of milk. Milk and cream are often sold according to the amount of butterfat they contain.- Composition :The fatty acids of butterfat are typically composed as follows :...

 by R. P. Hansen and J. D. Morrison in 1964. The name of the substance is derived from pristane
Pristane
Pristane is a natural saturated terpenoid alkane obtained primarily from shark liver oil, from which its name is derived . It is also found in mineral oil and some foods...

 (2,6,10,14-tetramethylpentadecane), the corresponding hydrocarbon
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons from which one hydrogen atom has been removed are functional groups, called hydrocarbyls....

. Pristane was isolated from shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....

 liver and was named after Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

pristis, "shark".
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