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, lipide
Biochem any of a large group of organic compounds that are esters of fatty acids (simple lipids, such as fats and waxes) or closely related substances (compound lipids, such as phospholipids): usually insoluble in water but soluble in alcohol and other organic solvents. They are important structural materials in living organisms


One of a class of compounds which contains long-chain aliphatic hydrocarbons (cyclic or acyclic) and their derivatives, such as acids (fatty acids), alcohols, amines, amino alcohols, and aldehydes. The presence of the long aliphatic chain as the characteristic component of lipids confers distinct solubility properties on the simpler members of this class of naturally occurring compounds.

The lipids are generally classified into the following groups:

  • A. Simple lipids
    • 1. Triglycerides or fats and oils are fatty acid esters of glycerol. Examples are lard, corn oil, cottonseed oil, and butter.
    • 2. Waxes are fatty acid esters of long-chain alcohols. Examples are beeswax, spermaceti, and carnauba wax.
    • 3. Steroids are lipids derived from partially or completely hydrogenated phenanthrene. Examples are cholesterol and ergosterol.
  •  B. Complex lipids
    • 1. Phosphatides or phospholipids are lipids which contain phosphorus and, in many instances, nitrogen. Examples are lecithin, cephalin, and phosphatidyl inositol.
    • 2. Glycolipids are lipids which contain carbohydrate residues. Examples are sterol glycosides, cerebrosides, and plant phytoglycolipids.
    • 3. Sphingolipids are lipids containing the long-chain amino alcohol sphingosine and its derivatives. Examples are sphingomyelins, ceramides, and cerebrosides.

Lipids are present in all living cells, but the proportion varies from tissue to tissue. The triglycerides accumulate in certain areas, such as adipose tissue in the human being and in the seeds of plants, where they represent a form of energy storage. The more complex lipids occur closely linked with protein in the membranes of cells and of subcellular particles. More active tissues generally have a higher complex lipid content; for example, the brain, liver, kidney, lung, and blood contain the highest concentration of phosphatides in the mammal. See Fat and oil, Fat and oil (food), Glycolipid, Sphingolipid, Steroid, Terpene, Triglyceride, Vitamin, Wax, animal and vegetable


One of a class of compounds which contain long-chain aliphatic hydrocarbons and their derivatives, such as fatty acids, alcohols, amines, amino alcohols, and aldehydes; includes waxes, fats, and derived compounds. Also known as lipin; lipoid.
References in periodicals archive ?
This is the first paper to show that rather than being a 'second hit' to help initiate the disease, blocking lipid synthesis alone -- with no other insult to the lungs -- can instigate fibrotic scaring," said researcher Ross Summer.
Systane Balance contains Alcon's LipiTech System, a proprietary emulsion technology that is said to allow the polar and non-polar lipids in Systane to exist as a metastable microemulsion.
Currently, worldwide, many laboratories follow the policy of an overnight fast for a minimum of 8 hours before obtaining samples for testing the lipid profile.
Measurements of nonfasting routine lipid samples have clear advantages that include (a) ease of sample collection timing for the patients and clinicians, (b) reduced burden on laboratories in the morning due to fasting status requirements, and (c) increase in compliance rates of lipid testing.
Estimation of Biomass was done by gravimetric method (Richmond and Gobbelaaar, 1986) chlorophyll by solvent extraction method (Lichtenthaler and Buschmann, 2001) and for initial screening , extraction of lipid by chloroform/ methanol (2:1) was carried out for all 26 isoalates (lee et al.
The scientists measured cook loss, textural properties and lipid oxidation (TBARS).
Fasting times showed little association with lipid subclass levels in a community-based population, which suggests that fasting for routine lipid levels is largely unnecessary.
In a study involving nearly 28,000 CHD patients who made a primary care visit to a Veterans Affairs medical center or community-based outpatient clinic during a 1-year period, 12,686 such "redundant" lipid panels were performed at an average cost of about $16 each.
According to the authors, "Collectively, these 9,200 patients with CHD had a total of 12,686 additional lipid panels performed.
Bolstering the supply of these lipids might help preserve these nerve coatings and, in the process, knock back the inflammation that contributes to their destruction, researchers report in the June 6 Science Translational Medicine.
Faster lipid production means more membranes are being made, which means more growth.
Scientists studying the components of protective nerve coatings that are damaged by multiple sclerosis (MS) have identified a handful of lipid molecules that are actively attacked by an immune system run amok.