Lipids (1. LF UK, NT)

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They are natural non-polar compounds that are insoluble in water, but are soluble in non-polar solvents.

Importance of lipids[edit | edit source]

  • they are one of the basic components of food, they serve as a source and reserve of energy (38kJ/g)
  • structural function - they are part of biomembranes (eg: double layer of phospholipids -> form micelles)
  • protective function - they cover some organs and thus protect them from shock
  • thermal insulation
  • solvents of non-polar vitamins (A, D, E, K)
  • precursors

Divisions[edit | edit source]

Simple[edit | edit source]

they contain only the lipid part

  • acylglycerols - are esters of VMK and glycerol (fats and oils)

- triacylglycerols are the most abundant in the human diet

  • waxes (animal, vegetable)
Lipid bilayer and micelle.png
Bilayer of phospholipids and micelle

Composite[edit | edit source]

obsahují lipidovou a nelipidovou část

  • they contain a lipid and a non-lipid part
  • glycoacylglycerols - contain a carbohydrate component

- are part of plant membranes

  • phosphoacylglycerols - are part of biological membranes and lipoproteins

- their molecule is amphipathic

  • sphingolipids - their basis is a compound that contains the 18-carbon amino alcohol sphingosine

- they are further divided into sphingomyelins containing ceramide and choline, these include cerebrosides and gangliosides containing carbohydrate and sialic acid - they are amphipathic and are found in the brain and nerves

Derived[edit | edit source]

  • terpenes
  • steroids

Higher fatty acids[edit | edit source]

They are the basic component of lipids. They have a high number of C, a high number of non-polar bonds and only one functional group - COOH, which is polar. They are unbranched, have a hydrophobic character and a cis arrangement that is natural in nature and our body can break it down.

Glycerol[edit | edit source]

=propane-1,2,3-triol, glycerin
It is a sweet viscous liquid, infinitely miscible with water.

Source of dietary fat[edit | edit source]

extraction of crude fats and oils, sources

  • vegetable – pressing, extraction
  • animal – smelting, extraction

Vegetable fats and oils[edit | edit source]


  • slime removal (hydration), vegetable slimes, proteins, their complexes - lecithin
  • deacidification (neutralization) – acid salts
  • whitening – carotenoids , chlorophylls
  • deodorization – tocopherols , sterols

Classification[edit | edit source]

By consistency

  • oils (liquid)
    • drying - linen
    • semi-drying - sunflower/soybean
    • non-drying - olive
  • fats (plastic, mushy) – lard
  • waxes (hard, non-greasy) – beeswax

By structure

  1. fatty acids and their soaps R-[CH2]n-COOH
  2. homolipids (esters of fatty acids with alcohols)
    1. monohydric alcohols (waxes)
      • aliphatic (cerides)
        • CH3-[CH2]25-OH... ceryl alcohol (beeswax)
        • H3-[CH2]15-OH... hexadecan-1-ol, cetyl alcohol (cetaceum)
      • alicyclic (steroids) - esters of sterols (cholesterol), triterpene alcohols
    2. dihydric alcohols (glycols), Alkoxylipids: 1-Alkoxypropane-2,3-diols Chimyl alcohol Ether-glycerolu.jpg Tuk žraloka.jpg
    3. trihydric (glycerol) Glycerol-3syt.jpg fats and oils
    4. polyhydric alcohols:
      • sugers – glycolipids
        • galactose, galactosides, digalactosides, diacylglycerogalactoside (diacylgalactosylglycerol) Glykolipidy.jpg
      • sacrose (1–3 MK emulsifiers, 6–8 MK low-energy fats (OLESTRA))
      • sorbitol (sugar alcohols) emulsifiers
  3. heterolipids 0.5–2%
    • glycerol , MK, another component
    • phospholipids (MK esters) Fosfolipidy.jpg
    • lipid sulfates (MK esters) Sulfátylipidu.jpg
    • sulfolipids Sulfolipidy.jpg
    • lipamides (MK amides) Lipamidy.jpg
    • serinolSerinol.jpg , ceramides Ceramidy.jpg, cerebrosides Cerebrosidy.jpg
  4. complex lipids
    • proteolipids ( lipoproteins )
    • glycolipids (cerebrosides)
    • mucolipids (sialoglycosphingolipids = gangliosides)

Links[edit | edit source]

Related articles[edit | edit source]

References[edit | edit source]