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Weiße Biotechnologie

Was wissen sie über Single Cell Oils in der Biotechnologie, welcher Organismus produziert welche Single Cell Oils ?

  • Öle als Nahrungsmittelergänzungsstoffe.
  • Aus Kostengründen nur für Fettsäuren sinnvoll, die mit Pflanzen und Säugetieren nicht produziert werden können
    • Stichwort Functional Food.
Mortierella alpina - Arachidonsäure
Crypthecodinium cohnii - Docosahexaensäure


Arachidonsäure [20:4(ω-6)]
  • Produktion mit Mortierella alpina (Pilz)
  • Bis 50 % Lipid, davon 40 % als Arachidonsäure

Docosahexaensäure [22:6(ω-3)]
  • Produktion mit Crypthecodinium cohnii (heterotrophe marine Alge)
  • gehört zu Omega-3 FS, in der Nahrung z.B. im Lachs über Nahrungskette aus Mikroalgen.
  • Interessant ev bei Gegenüberstellung der ökologischen Auswirkungen von Fish-Farming zu Isolation der Fettsäuren.
 
 
--> Alternativ ev. zukünftig interessant: Biodieselproduktion von Mikroalgen und Pilzen
 
Weitere Anmerkungen:
Single cell oils (SCO) are the edible oils extracted from micro-organisms-the single-celled entities that are at the bottom of the food chain.The best producers with the highest oil contents are various species of yeasts and fungi with several key algae that are also able to produce high levels of nutritionally important PUFA. Their potential to produce PUFA has now galvanized the current interest in these SCO as oils rich in highly desirable fatty acids essential for our well being and not readily available either from plants or animals
 
Microorganisms have been receiving increased attention as sources of novel lipids. Those that accumulate more than 20-25 % of their biomass as oil may be termed oleaginous and their oils single cell oils (SCOs), unicellular oils or microbial oils. For the lipid accumulation in yeasts, moulds and eukaryotic algae, but not in bacteria, the presence of enzyme ATP-cytrate lyase is of vital importance. This enzyme serves to produce acetyl-CoA, which is the substrate for fatty acid biosynthesis. Nitrogen limitation is the most frequently used condition to favour lipid accumulation. Oleaginous organisms differ from nonoleaginous ones in being able to convert carbon from the growth medium into the intracellular lipid, after the nitrogen has been depleted from the medium, provided that the supply of carbon stays plentiful. Biosynthetic pathways of n-6 and n-3 polyunsaturated fatty acids from the saturated and monounsaturated precursors with the chain elongations and desaturations are presented. The suitability of an microalgal triglyceride-SCO highly enriched in docosahexaenoic acid (DHASCO  ) as a source for nutritional supplementation for formula milk is compared to fish oil. Some safety evaluation studies of SCOs are presented. For the safe use of SCOs in infant formulas even further safety studies should be performed. By growing microalgal strains in a medium containing D-(1- 13 C)glucose, SCOs enriched with the stable isotope 13 C can be produced. Some examples of recent research and diagnostic applications of 13 C-labelled SCOs to study fatty acid metabolism are outlined. In conclusion, SCOs in combination with stable isotopes have become indispensable to study metabolic pathways.

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