Kinetic parameters of the glucuronidation of six isoflavones in jejunal and hepatic microsomes
Parametersa | Gen | Gly | Bio | Pru | Dai | For | |
|---|---|---|---|---|---|---|---|
| Jejunum | Vmax (total) (nmol/min/mg) | 3.171 | 1.92 | 1.841 | 1.62 | 0.646 | 0.495 |
| Km1 (μM) | 6.628 | 2.66 | 6.652 | 2.05 | 2.439 | 7.250 | |
| Vmax1/Km1 (ml/min/mg) | 0.478 | 0.72 | 0.276 | 0.79 | 0.265 | 0.068 | |
| Vmax-0 (autoact) (ml/min/mg) | |||||||
| Vmax-d (autoact) (nmol/min/mg) | |||||||
| Vmax2 (biphasic) (nmol/min/mg) | 0.157 | ||||||
| Km2 (μM) | 1.73E-4 | ||||||
| R 2 | 0.995 | 0.997 | 0.972 | 0.991 | 0.999 | 0.981 | |
| R (autoact only) | |||||||
| AIC | -19.13 | -35.72 | -15.83 | -33.89 | -52.96 | -42.32 | |
| Liver | Vmax1 (nmol/min/mg) | 3.713 | 3.720 | 1.250 | 0.343 | 1.190 | 1.384 |
| Km1 (μM) | 23.6 | 1.034 | 0.196 | 0.834 | 1.119 | 2.225 | |
| Vmax1/Km1 (ml/min/mg) | 0.157 | 3.598 | 6.351 | 0.411 | 1.063 | 0.622 | |
| Vmax2 (biphasic) (nmol/min/mg) | 0.826 | 1.647 | |||||
| Km2 (μM) | 0.71E-7 | 16.65 | |||||
| Ksi (inhibition) | 5920 | ||||||
| R 2 | 0.989 | 0.960 | 0.991 | 0.978 | 0.991 | 0.985 | |
| R (autoact only) | |||||||
|
| AIC | -17.9 | -9.13 | -27.01 | -32.82 | -42.93 | -31.89 |
GEN, genistein; GLY, glycitein; BIO, biochanin A; PRU, prunetin; DAI, daidzein; FOR, formononetin.
↵ a Atypical kinetics identified as autoact, autoactivation; biphasic, biphasic kinetics; and inhibition, substrate inhibition.