The intensity of 7-hydroxycoumarin
fluorescence was measured at excitation and emission wavelengths of 338 and 458 nm, respectively.
Reversible binding of 7-hydroxycoumarin
(7-HC) to bSULT1A1 is detected by enhanced ligand emission at 400 nm, and previous titrations suggested a Kd for 7-HC of 0.
On the basis of IR, NMR and mass spec data, this compound was shown to be umbelliferone ot 7-hydroxycoumarin
The fluorescent metabolite 7-hydroxycoumarin
was measured using a Perkin--Elmer spectrofluorimeter, excitation wavelength 370nm; emission wavelength 474 nm.
Antitumour-activities of coumarin, 7-hydroxycoumarin
and its glucuronide in several human tumour cell lines.
Phenol sulfotransferase (SULT1A1) catalyses sulfuryl group transfer from 3'phosphoadenosine-5'-phosphosulafe (PAPS) to phenolic xenobiotics such as 7-hydroxycoumarin
Nine compounds were studied: 4-hydroxybenzaldehyde, salicylaldehyde, acetanilide, 4-hydroxycoumarin, 7-hydroxycoumarin
, indole-3, carboxaldehyde, salicylic acid, cinnamic acid and 2-hydroxy cinnamic acid.
These were 7-ethoxyresorufin and resorufin for CYP1A2; coumarin and 7-hydroxycoumarin
for CYP2A6; 7-ethoxy-4-(trifluoromethyl) coumarin (EFC) and 7-hydroxy-4-(trifluoromethyl) coumarin (HFC) for CYP2B6; dibenzylfluorescein (DBF) and fluorescein for CYP2C8 and CYP2C19; 7-methoxy-4-(trifluoromethyl) coumarin (MFC) and HFC for CYP2C9 and CYP3A4; and 7-methoxy-4-(aminomethyl) coumarin (MAMC) and 7-hydroxy-4-(aminomethyi) coumarin (HAMC) for CYP2D6.
Fluorescence samples were quantified by a calibration curve with resorufin or 7-hydroxycoumarin
standards, using 535 or 380 nm (excitation wavelength) and 585 or 460 nm (emission wavelength), respectively.
Apoptosis and cell cycle disturbances induced by coumarin and 7-hydroxycoumarin
on human lung carcinoma cell lines.
CYP2A6 is one of the genetically polymorphic enzymes, known to be expressed predominantly in the liver and to be an exclusive catalyst of a conversion of coumarin to 7-hydroxycoumarin
(7-OHC; Oscarson 2001; Pelkonen et al.
In general, troxerutin reduces the concentration of all coumarin-metabolites in the perfusate and bile and changes the ratio of the main metabolites, coumarin: 3-hydroxycoumarin: 7-hydroxycoumarin