Lipider – fett, oljor, etc

aak-lipids-essential_skin_nutrients_from_vegetable-oils_lipidernas-anvandningsomrade-i-hudvard

Kärnor, frön och vissa frukter har ofta ett högt innehåll av lipider, något vi utvinner som vegetabiliska oljor och ett antal andra fettliknande ämnen. Bild AAK Academy.

Lipider från vegetabiliska oljor – Essentiella näringsämnen för huden

Termen Lipid saknar en exakt definition. Det finns flera olika sätt att förklara och dela in gruppen lipider, men för närvarande verkar den mest vedertagna definitionen vara:

"Lipids are fatty acids and their derivatives, and substances related biosynthetically or functionally to these compounds" (S.S. Christie)

På Wikipedia får ovanstående formulering ännu en lite närmare förklaring: 
"Lipider är inom kemin ett samlingsnamn på en stor grupp ämnen bestående av fetter och fettliknande ämnen. Själva definitionen av en lipid är otydlig och vag men det omfattar vanligtvis ämnen från levande organismer som är lösliga i opolära lösningsmedel och olösliga i vatten. Det är således främst ämnets fysikaliska egenskaper och biologiska förekomst som avgör huruvida ämnet är en lipid eller inte."

Gruppen lipider innefattar:

  • Fettsyror och estrar
  • Glycerider – mono-, di- och triglycerider (varav triglycerider är den mest förekommande formen av lipider i vegetabiliska oljor)
  • Steroler – kolosterol, phytosterol etc
  • Vaxer och vaxestrar – lanolin, bivax etc
  • Tokoferoler – Vitamin E
  • Komplexa lipider – fosfolipiderglycolipider etc
 

lipids-essential_skin_nutrients_from_vegetable_aak-academy

Lipider återfinns såväl inne i cellkärnan såväl som i dess membram. Bild AAK Academy.
 

Lipids – Essential skin nutrients from vegetable oils

After two days of truely inspirational deep focus on lipids at AAK Academy in Karlshamn this October, I would like to share some of what I have learnt. First out: What is a Lipid?

I think I am making a pretty good guess when I believe that most of us at least a couple of times have stumbled upon the word "Lipid" during our excursions in the cosmetic jungle. And like me, I guess most of us have had a pretty vague clue of what this term exactly means. Now I can comfort you with the fact that the term "Lipid" is pretty vague even for an expert, this beacause there is no exakt definition of this term. How ever, at this date, one of the most commonly definitions referred to when it comes to Lipids is this one:

"Lipids are fatty acids and their derivatives, and substances related biosynthetically or functionally to these compounds" (S.S. Christie)

A some what more thourough explanation can be found at Wikipedia:

"Lipids are a group of naturally occurring molecules that include fatswaxessterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglyceridesdiglyceridestriglyceridesphospholipids, and others. The main biological functions of lipids include storing energy, signaling, and acting as structural components of cell membranes.[4][5] Lipids have applications in the cosmetic and food industries as well as in nanotechnology.[6]

Lipids may be broadly defined as hydrophobic or amphiphilic small molecules; the amphiphilic nature of some lipids allows them to form structures such as vesicles, multilamellar/unilamellar liposomes, or membranes in an aqueous environment. Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups.[4] Using this approach, lipids may be divided into eight categories: fatty acidsglycerolipidsglycerophospholipidssphingolipidssaccharolipids, and polyketides (derived from condensation of ketoacyl subunits); and sterol lipids and prenol lipids (derived from condensation of isoprene subunits).[4]

Although the term lipid is sometimes used as a synonym for fats, fats are a subgroup of lipids called triglycerides. Lipids also encompass molecules such as fatty acids and their derivatives (including tri-di-monoglycerides, and phospholipids), as well as other sterol-containing metabolites such as cholesterol.[7] Although humans and other mammals use various biosynthetic pathways to both break down and synthesize lipids, some essential lipids cannot be made this way and must be obtained from the diet."

Lipids includs:

  • Fatty acids and their esters with simple alcohols 
  • Glycerides – mono-, di- and tri-acylglycerols
  • Sterols and sterol esters – incl. cholesterol, phytosterols etc.
  • Waxes and wax esters – incl. lanolin, bees wax etc.
  • Tocopherols – Vitamin E
  • Complex lipids – phospholipids and glycolipids
 

Källa: 

AAK Academy
https://en.wikipedia.org/wiki/Lipid