Table 3.

The caspase-9 activity of Hep G₂ cells after 48 h treatment with various concentrations of studied compounds (silybin A (SA), silybin B (SB), 3-O-galloyl silybin A (SGA) and 3-O-galloyl silybin B (SGB)) determined by measuring optical absorbance of p-nitroanilide. All data are shown as mean ± SD; n = 3. *Significant difference at P<0.05 compared to control group according to one-way ANOVA, followed by Tukey›s post-hoc test

Concentrations (micro molar)	Caspase-9 (ΔOD 405nm)
	SA	SB	SGA	SGB
0 (Control)	0.26 + 0.034
25	0.41 + 0.060*	0.30 + 0.048	0.23 + 0.029	0.30 + 0.048
50	0.50 + 0.089*	0.41 + 0.055*	0.40 + 0.053*	0.41 + 0.053*
75	0.61 + 0.102*	0.47 + 0.070*	0.55 + 0.070*	0.46 + 0.046*
100	0.73 + 0.110*	0.56 + 0.067*	0.86 + 0.136*	0.53+ 0.077*
125	0.84 + 0.133*	0.60 + 0.083*	0.69 + 0.103*	0.70 +0.093*
150	0.96 + 0.143*	0.67 + 0.105*	0.80 + 0.124*	0.89 + 0.108*
175	1.10 + 0.164*	0.81 + 0.126*	1.19 + 0.147*	1.18 + 0.192*
200	1.16 + 0.147*	0.89 + 0.114*	1.30 + 0.167*	1.34 + 0.207*