Reaction: baicalin + H2O = baicalein + D-glucuronate
Glossary: baicalin = 5,6,7-trihydroxyflavone-7-O-β-D-glucuronate = 5,6-dihydroxy-4-oxo-2-phenyl-4H-chromen-7-yl β-D-glucupyranosiduronic acid
baicalein = 5,6,7-trihydroxyflavone = 5,6,7-trihydroxy-2-phenyl-4H-chromen-4-one
wogonin = 5,7-dihydroxy-8-methoxyflavone = 5,7-dihydroxy-8-methoxy-2-phenyl-4H-chromen-4-one
oroxylin = 5,7-dihydroxy-6-methoxyflavone = 5,7-dihydroxy-6-methoxy-2-phenyl-4H-1-benzopyran-4-one
Other name(s): baicalinase
Systematic name: 5,6,7-trihydroxyflavone-7-O-β-D-glucupyranosiduronate glucuronosylhydrolase
Comments: The enzyme also hydrolyses wogonin 7-O-β-D-glucuronide and oroxylin 7-O-β-D-glucuronide with lower efficiency [4]. Neglegible activity with p-nitrophenyl-β-D-glucuronide [2].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Ikegami, F., Matsunae, K., Hisamitsu, M., Kurihara, T., Yamamoto, T. and Murakoshi, I. Purification and properties of a plant β-D-glucuronidase form Scutellaria root. Biol. Pharm. Bull. 18 (1995) 1531-1534. [PMID: 8593473]
2. Zhang, C., Zhang, Y., Chen, J. and Liang, X. Purification and characterization of baicalin-β-D-glucuronidase hydrolyzing baicalin to baicalein from fresh roots of Scutellaria viscidula Bge. Proc. Biochem. 40 (2005) 1911-1915.
3. Sasaki, K., Taura, F., Shoyama, Y. and Morimoto, S. Molecular characterization of a novel β-glucuronidase from Scutellaria baicalensis Georgi. J. Biol. Chem. 275 (2000) 27466-27472. [PMID: 10858442]
4. Morimoto, S., Harioka, T. and Shoyama, Y. Purification and characterization of flavone-specific β-glucuronidase from callus cultures of Scutellaria baicalensis Georgi. Planta 195 (1995) 535-540.