Stanol ester Stanol ester Stanol ester is a heterogeneous group of chemical compounds known to reduce the level of low-density lipoprotein (LDL) cholesterol in blood when ingested, though to a much lesser degree than prescription drugs such as statins. The starting material is phytosterols from plants. These are first hydrogenated to give a plant stanol which is then esterified with a mixture of fatty acids also derived from plants. Plant stanol esters are found naturally occurring in small quantities in fruits, vegetables, nuts, seeds, cereals, legumes, and vegetable oils. Stanol ester is often added to rapeseed oil based margarine or other foods
Discovery and development of statins must be metabolized to their active hydroxy-acid forms in order to inhibit HMGR. Type 2 statins all exist in their active hydroxy-acid forms. Fluvastatin has indole ring structure, while atorvastatin and rosuvastatin have pyrrole and pyrimidine based ring structure respectively. The lipophilic cerivastatin has a pyridine-based ring structure. Studies have shown that statins bind reversibly to the HGMR enzyme. The affinity of statins for HGMR enzyme is in the nanomolar range, while the natural substrate's affinity is in the micromolar range. Studies have shown that statins use the conformational flexibility of the HMGR enzyme that causes a shallow hydrophobic groove