betaDglucuronyl

Beta-D-glucuronyl refers to the glucuronyl residue derived from D-glucuronic acid, typically in the beta anomeric form as part of glucuronides. In biochemical contexts, the beta-D-glucuronyl group is usually linked to a substrate via an O-glycosidic bond, forming a glucuronide. The linkage is established by UDP-glucuronosyltransferases, which transfer glucuronic acid from UDP-glucuronic acid to a wide range of substrates, including xenobiotics, phenols, alcohols, carboxylic acids, and steroids.

Role and significance: Glucuronidation increases water solubility and facilitates renal or biliary excretion, making it a central detoxification pathway in the liver and other tissues. Endogenous substrates include bilirubin and various hormones, while many pharmaceuticals are rapidly glucuronidated to promote clearance. Glucuronides can be hydrolyzed back to aglycones by beta-glucuronidases in certain tissues, enabling localized reactivation of compounds.

Occurrence and context: Glucuronyl residues are abundant in natural products, drug metabolites, and conjugates formed during Phase II metabolism. In analytical and pharmacokinetic studies, glucuronides are routinely detected and quantified using methods such as mass spectrometry, reflecting their prevalence in drug disposition and metabolism.

Notes: The term beta-D-glucuronyl highlights the stereochemistry of the glucuronic acid moiety and its common beta-linkage in glucuronides, distinguishing it from other uronic or glycosidic forms.