page_title: Squalene
section_title: Role in steroid synthesis
hierarchical_section_title: Squalene / Role in steroid synthesis
context_page_description: Squalene is a natural organic compound originally obtained for commercial purposes primarily from shark liver oil, although plant sources are now used as well, including amaranth seed, rice bran, wheat germ, and olives. Yeast cells have been genetically engineered to produce commercially useful quantities of "synthetic" squalene.
  All plants and animals produce squalene as a biochemical intermediate, including humans. It occurs in high concentrations in the stomach oil of birds in the order Procellariiformes. Squalene is a hydrocarbon and a triterpene, and is a precursor for synthesis of all plant and animal sterols, including cholesterol and steroid hormones in the human body.
context_section_description: Squalene is the biochemical precursor to the whole family of steroids. Oxidation (via squalene monooxygenase) of one of the terminal double bonds of squalene yields 2,3-squalene oxide, which undergoes enzyme-catalyzed cyclization to afford lanosterol, which is then elaborated into cholesterol and other steroids.
  Squalene is an ancient molecule. In plants, squalene is the precursor to stigmasterol. In certain fungi, it is the precursor to ergosterol. However, blue-green algae and some bacteria do not manufacture squalene, and must acquire it from the environment if they need it. Metabolomics has revealed that Camellia japonica leaf contains pentacyclic triterpenoid anti-inflammatory compound, lupeol which is produced from the precursor squalene.
caption: Simplified version of the steroid synthesis pathway with the intermediates isopentenyl pyrophosphate (IPP), dimethylallyl pyrophosphate (DMAPP), geranyl pyrophosphate (GPP) and squalene shown. Some intermediates are omitted.