Table 5.
Antiproliferative analysis against human melanocytes and the percentage melanin produced by the EtOH extract of Aspalathus linearis, its fractions and the compounds, exhibiting an increase in the tyrosinase enzyme rate.
| Samples | Antiproliferative IC50c (µg/mL) ± standard deviation | Masson Fontana % increase in melanin produced (100 µg/mLd) |
|---|---|---|
| A. linearis EtOH extract | 345.50 ± 2.47 | 5.18% |
| AcOH fraction | 208.50 ± 1.08 | 4.87% |
| EtOAc fraction | 231.70 ± 1.09 | 7.04% |
| EtOH fraction | 230.70 ± 1.09 | 4.78% |
| H2O fraction | 359.60 ± 1.15 | 5.67% |
| Aspalathin (1) | 217.75 ± 1.23 (481.60 µM) | 3.77% |
| Catechin (3) | 166.32 ± 1.14 (573 µM) | 5.72% |
| αMSHa | > 100 (60 µM) | 9.73%e |
| Actinomycin Db | 0.039 ± 0.002 | N/A |
aPositive control for the Masson Fontana assay.
bPositive control for the antiproliferative assay.
cConcentration where 50% of the cells are viable.
dPositive control tested at 30 µg/mL (18 µM).