TABLE 2. Production of metabolites related to M1, M2, M3, and M4 (from capsaicin) from various capsaicinoid analogs by human liver microsomes.
Values represent the average percentage and standard deviation for metabolite production, relative to capsaicin, from three separate incubations. Incubations were performed as described under Materials and Methods using the semiquantitative method for assessing metabolite formation.
| Capsaicinoid Analog and Description | Relative Metabolite Production Versus Capsaicin | |||
|---|---|---|---|---|
| % | ||||
| Saturated analogs | Macrocycle | ω-OH | ω-1-OH | Terminal alkene |
| Nordihydrocapsaicin | 3.3 ± 0.9 | 90 ± 14 | N.D. | 15 ± 4 |
| Dihydrocapsaicin | 6 ± 2 | 180 ± 15 | N.D. | 23 ± 9 |
| Homodihydrocapsaicin | 10 ± 2 | 193 ± 7 | N.D. | 29 ± 6 |
| Straight-chain analogs | Macrocycle | ω-OH | ω-1-OH | Terminal alkene |
| n-Vanillyloctanamide | N.D. | 54 ± 5 | N.D. | 3 ± 1 |
| Nonivamide | N.D. | 135 ± 8 | N.D. | 6 ± 3 |
| n-Vanillyldecanamide | N.D. | 170 ± 15 | N.D. | 14 ± 5 |
| Increased chain lengths | Macrocycle | ω-OH | ω-1-OH | Diene |
| Homocapsaicin | 48 ± 8 | 50 ± 13 | 60 ± 12 | 8 ± 1 |
N.D., not detected.