Thermomyces lanuginosus lipase catalyzed transesterification of sterols by methyl oleate

Plant steryl and stanyl esters are effective in lowering plasma cholesterol concentration by inhibiting the absorption of cholesterol from small intestine. They are, therefore, used as constituents of special margarines, which are commercially available as functional foods with the ability to reduce blood cholesterol levels. An enzymatic method has been developed for the preparation of oleic acid esters of sterols and stanols in high yield by transesterification of methyl oleate with the 3‐hydroxy group in vacuo (20‐40 hPa) at moderate temperature (80 °C) using immobilized lipase preparation from Thermomyces lanuginosus (Lipozyme TL IM®) as biocatalyst. Neither an organic solvent nor a drying agent are required. Cholesterol and stanols such as 5α‐cholestanol and sitostanol have been converted at similar rates and in near‐quantitative yields (>95%) to the corresponding oleic acid esters.