Columbianadin (Zosimin), one of the main bioactive constituents of the roots of Angelica pubescens Maxim. f. biserrata Shan et Yuan, has been found to possess obvious pharmacological effects in previous studies.

Cells are treated with various concentrations of Dihydrotanshinone I (3.13-20 μM) for 48 h. For the activity assay, Ac-DEVD-AMC (1 μg/μL), Ac-IETD-AMC (1 μg/μL) or Ac-LEDH-AMC (1 μg/μL) and cell lysate are added into Protease Assay Buffer in 96-well plate. Reaction mixtures with lysis buffer are used as negative controls. Cells treated with DMSO (0.1%) are treated as vehicle control. The reaction mixtures are incubated for 1 h at 37°C. The AMC liberated from the substrates is measured using spectrofluorometer of Victor 2 plate reader with an excitation wavelength of 380 nm and an emission wavelength of 430 nm.