In enzymology, a sarsasapogenin 3β-glucosyltransferase is an enzyme that catalyzes the chemical reaction Thus, the two substrates of this enzyme are UDP-glucose and sarsasapogenin [(3β,5β,25S)-spirostan-3-ol], whereas its two products are UDP and sarsasapogenin 3-O-β- D -glucoside. The enzyme was first isolated from the root of the common asparagus (Asparagus officinalis). It is specific for substrate sterols with the uncommon 5β-configuration (sarsasapogenin and smilagenin), that is with a cis-linkage between the A and B rings of the steroid nucleus. This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-glucose:(3β,5β,25S)-spirostan-3-ol 3-O-β- D -glucosyltransferase. This enzyme is also called uridine diphosphoglucose-sarsasapogenin glucosyltransferase.