[Sterol formation by Canida boidinii]

The content of sterols in the yeast Candida boidinii is low: 0.35--0.40% in a mineral medium with methanol as a sole carbon source; 0.55--0.60% in a medium with ethanol; 0.50--0.60% in a medium with glucose; 0.50--0.55% on wort--agar. Ergosterol is the main sterol in all of the cases. sterols are found mainly in the bound state as esters, and constitute about 90% of the total sterol content. Free sterols constitute only 10%. The level of sterols in this culture is rather constant and hardly changes within the first days of cultivation. The content of sterols increases only slightly (by 30--40%) when the culture ages.