lipid


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lipid

 [lip´id]
a group of substances comprising fatty, greasy, oily, and waxy compounds that are insoluble in water and soluble in nonpolar solvents, such as hexane, ether, and chloroform.

Simple lipids are the triglycerides or neutral fats. Each triglyceride molecule is composed of one molecule of glycerol joined by ester linkages to three fatty acid molecules. They are an important source of fuel to the body and a much lighter form of energy storage than carbohydrate.

Compound lipids are important structural components of cell membranes. Phospholipids include lecithin and the cephalins, which are composed of fatty acids linked to phosphatidic acid, and the sphingomyelins, which are composed of fatty acids linked to sphingosine. Glycolipids are composed of a carbohydrate chain and fatty acids linked to sphingosine or ceramide. Cholesterol is a steroid alcohol. Another important function of the phospholipids is as lung surfactants.

Intravenous lipid emulsions can be administered to patients with a deficiency of essential fatty acids.

lip·id

(lip'id),
"Fat-soluble," an operational term describing a solubility characteristic, not a chemical substance, that is, denoting substances extracted from animal or vegetable cells by nonpolar solvents; included in the heterogeneous collection of materials thus extractable are fatty acids, glycerides and glyceryl ethers, phospholipids, sphingolipids, long-chain alcohols and waxes, terpenes, steroids, and "fat-soluble" vitamins such as A, D, and E.
[G. lipos, fat]

lipid

/lip·id/ (lip´id) any of a heterogeneous group of fats and fatlike substances, including fatty acids, neutral fats, waxes, and steroids, which are water-insoluble and soluble in nonpolar solvents. Lipids, which are easily stored in the body, serve as a source of fuel, are an important constituent of cell structure, and serve other biological functions. Compound lipids comprise the glycolipids, lipoproteins, and phospholipids.

lipid

(lĭp′ĭd, lī′pĭd) also

lipide

(lĭp′īd′, lī′pīd′)
n.
Any of a group of organic compounds, including the fats, oils, waxes, sterols, and triglycerides, that are insoluble in water but soluble in nonpolar organic solvents, are oily to the touch, and together with carbohydrates and proteins constitute the principal structural material of living cells.

lip·id′ic adj.

lipid

[lip′id, lī′pid]
Etymology: Gk, lipos, fat, eidos, form
any of a structurally diverse group of organic compounds that are insoluble in water but soluble in alcohol, chloroform, ether, and other solvents. Some lipids are stored in the body and serve as an energy reserve but are elevated in various diseases such as atherosclerosis. Kinds of lipids include cholesterol, fatty acids, phospholipids, and triglycerides. The normal concentrations of lipids in serum are total, 400 to 800 mg/dl; cholesterol, 150 to 250 mg/dl; fatty acids, 9 to 15 mM/L; phospholipids, 150 to 380 mg/dl; phospholipid as phosphorus, 9 to 16 mg/dl; and triglycerides, 10 to 190 mg/dl.

LIPID

Cardiology A clinical trial–Long-Term Intervention with Pravastatin in Ischemic Disease–which evaluated preventing cardiovascular M&M with pravastatin in Pts with CAD and a range of initial cholesterol levels

lip·id

(lip'id)
"Fat-soluble," an operational term describing a solubility characteristic, not a chemical substance, i.e., denoting substances extracted from animal or vegetable cells by nonpolar solvents; included in the heterogeneous collection of materials thus extractable are fatty acids, glycerides, glyceryl ethers, phospholipids, sphingolipids, long-chain alcohols, waxes, terpenes, steroids, and "fat-soluble" vitamins such as A, D, and E.

lipid

a biological compound composed of glycerol and fatty acid components, containing carbon, hydrogen and oxygen together with other elements such as nitrogen and phosphorus. Lipids (or fats) are structural components of cell membranes and nervous tissue, and are important sources of energy, being stored in various parts of the body (see ADIPOSE TISSUE). They are important insulators and mechanical protectors. Their large molecular size makes lipids insoluble in water, but soluble in organic solvents such as acetone and ether. There are five lipid groups:

triglycerides (fats and oils)

phospholipids

glycolipids

sterols and steroids

waxes

Lipid

A greasy organic compound that cannot be dissolved in water. Triglycerides, which are broken down by lipase, are one type of blood lipid.

lipid,

n fat or a similar greasy substance that dissolves in alcohol and organic solvents but not in water.

lip·id

(lip'id)
"Fat-soluble," operational term describing a solubility characteristic, not a chemical substance, i.e., denoting substances extracted from animal or vegetable cells by nonpolar solvents.

lipid (lip´id),

n a heterogeneous group of substances related actually or potentially to the fatty acids that are soluble in nonpolar solvents such as benzene, chloroform, and ether and are relatively insoluble in water. Included are the fatty acids, acylglycerols, phospholipids, cerebrosides, and steroids.
lipid, plasma,
n the various plasma lipid classes include triacylglycerols, phospholipids, cholesterol, cholesterol esters, and unesterified fatty acids. Because of their hydrophobic nature, plasma lipids are carried in association with specific plasma proteins, the lipoproteins.

lipid

a group of substances comprising fatty, greasy, oily and waxy compounds that are insoluble in water and soluble in nonpolar solvents, such as hexane, ether and chloroform.
Simple lipids are the triglycerides or neutral fats. Each triglyceride molecule is composed of one molecule of glycerol joined by ester linkages to three fatty acid molecules. They are an important source of oxidizable substrate to the body and have a greater caloric density (2.25 times) than carbohydrate.
Compound lipids are important structural components of cell membranes. Phospholipids include lecithin and the cephalins, which are composed of fatty acids linked to phosphatidic acid, and the sphingomyelins, which are composed of fatty acids linked to sphingosine. Glycolipids are composed of a carbohydrate chain and fatty acids linked to sphingosine or ceramide. Cholesterol is a steroid alcohol. Another important function of the phospholipids is as lung surfactants.

lipid A
a component of the cell wall of gram-negative bacteria, responsible for their toxic properties.
lipid pneumonia
see lipid pneumonia.
protected l's
fats treated to protect them against microbial degeneration in the rumen.
lipid transport disease
a group of diseases in which there is a disorder of lipid metabolism with abnormal levels or types of lipoproteins in the blood, e.g. hyperlipoproteinemia, hyperlipemia.
References in periodicals archive ?
Summer and Romero used a drug that inhibited lipid production in the lung and showed that this drug alone was capable of instigating lung fibrosis.
Fasting and nonfasting lipid profiles are not mutually exclusive; rather, they are complementary tools in the testing algorithm for patient care.
Dry extraction procedure was used to extract the lipid in microalgal cells (Zhu et al.
The type of salt influenced raw meat redness, cooked meat hardness at 2% levels and lipid oxidation during storage, but not cook loss.
Is it time to eliminate the need for overnight fasting for lipid tests in patients with diabetes?
The study subjects had well-controlled lipid levels, with excellent mean baseline levels of LDL cholesterol (70mg/dL), non-HDL cholesterol (94 mg/dL), triglycerides (123 mg/dL), and HDL cholesterol (43 mg/dL).
But other details of MS, including the roles of myelin lipids, have been less clearly understood.
In the final step, each type of lipid is run through a mass spectrometer to measure the abundance of the [sup.
The role of myelin lipids have been less clearly understood in MS.
Purpose: The surface properties of lipid membranes were studied to elucidate the mechanisms of unspecific interactions with proteins.
com)-- PREMIER Biosoft International today announced the release of the second version of its innovative product, SimLipid, with support for MS/MS data analysis and correction of peak intensities for MS lipid profiles with overlapping isotopes.