Table 2.
In vitro enzymatic inhibition (%) of tyrosinase, collagenase and elastase by isolated compounds from Plectranthus spp.
| Enzymatic inhibition SD (%) |
|||
|---|---|---|---|
| Compound No. | Anti-tyrosinasea | Anti-collagenaseb | Anti-elastaseb |
| 1 | 46.6 4.7 | 33.5 3.2 | 29.3 2.8 |
| 2 | 14.7 2.0 | 24.0 3.0 | 39.2 5.2 |
| 3 | 75.7 3.6 | 60.6 9.7 | 38.3 4.4 |
| 4 | 72.7 5.6 | 84.6 5.9 | 52.8 3.8 |
| 5-6 (1:1 mixture) | NT | NT | NT |
| 7-8 (1:4 mixture) | NT | NT | 63.5 2.6 |
| 9 | 43.9 1.3 | 24.6 9.2 | 21.2 2.1 |
| 10 | 38.3 0.6 | 41.5 4.9 | 27.3 1.4 |
| 11 | 41.3 2.7 | 16.7 1.9 | 33.3 3.3 |
| 12-13 (1:1 mixture) | NT | NT | 6.15 3.5 |
| 14-15 (3:1 mixture) | NT | NT | 15.8 2.0 |
| 16 | 40.4 0.7 | NT | NT |
| 17 | 47.9 1.4 | 44.8 4.5 | NT |
| Positive control (compound) | 92.9 7.4 (Kojic acid) | 93.1 5.3 (EGCG) | 69.9 3.7 (Ursolic acid) |
aSamples tested at 50 g/mL, bsamples tested at 100 g/mL, NT, not tested; for compound number chemical structure assignments refer to Table 1. EGCG: epigallocatechin gallate.