Table 1 Activity (% inhibition) of Helichrysum crude extracts and major isolated compounds (1–6) in protease inhibition assays using pepsin and subtilisin
| Â | Inhibition of pepsin (%) | |||||
|---|---|---|---|---|---|---|
Sample | Concentration (μg/ml) | |||||
| Â | 50 | 25 | 10 | 1 | 0.1 | 0.01 |
H. mechowianum | 22.8 | 18.8 | 12.0 | 0.3 | 10.9 | 5.4 |
H. foetidum | 37.4 | 35.6 | 17.8 | nd | 12.6 | 7.1 |
1 | nd | 39.5 | nd | −14.2 | −1.5 | 0.4 |
2 | nd | 15.9 | 9.2 | −1.4 | nd | 0.3 |
3 | 37.4 | 37.4 | 20.1 | 18.2 | 19.4 | 8.0 |
4 | 11.6 | 0.2 | nd | 0.2 | 7.8 | 1.8 |
5 | 46.3 | 37.2 | 15.1 | 18.6 | −5.3 | −2.9 |
6 | 25.0 | −3.6 | nd | −39.0 | −1.2 | −8.0 |
12 | 10.5 | 0.7 | Nd | 0.4 | 6.2 | 2.3 |
13 | 14.7 | 16.4 | 11.8 | 13.7 | 13.1 | 6.1 |
| Â | Inhibition of subtilisin (%) | |||||
H. mechowianum |  |  | −4.8 | 0.2 | 3.0 | −0.1 |
H. foetidum | Â | Â | 0.9 | 2.1 | 4.0 | 3,8 |
1 | Â | Â | nd | nd | nd | nd |
2 |  |  | −11.6 | −26.2 | 13.2 | nd |
3 | Â | Â | 9.7 | 4.2 | 6.0 | 3.0 |
4 | Â | Â | 11.5 | 7.8 | 6.8 | nd |
5 |  |  | 9.2 | 0.3 | 1.0 | −4.8 |
6 |  |  | −11.6 | nd | −5.5 | 16.6 |
12 | Â | Â | 11.1 | 8.9 | 7.5 | Nd |
13 | Â | Â | 8.3 | 5.2 | 7.1 | 3.2 |