Table 2.

The caspase-3 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-3 (ΔOD 405nm)
	SA	SB	SGA	SGB
0 (Control)	0.38 + 0.043
25	0.45 + 0.055	0.34 + 0.050	0.35 + 0.038	0.45 + 0.065
50	0.58 + 0.080	0.45 + 0.060	0.46 + 0.062	0.56 + 0.070
75	0.65 + 0.098*	0.58 + 0.076	0.58 + 0.070	0.62 + 0.081*
100	0.79 + 0.107*	0.53 + 0.065	0.67 + 0.084*	0.78 + 0.095*
125	0.91 + 0.133*	0.62 + 0.095*	0.83 + 0.114*	0.98 + 0.128*
150	0.98 + 0.148*	0.73 + 0.105*	0.97 + 0.134*	1.21 + 0.160*
175	1.12 + 0.164*	0.82 + 0.130*	1.12 + 0.147*	1.53 + 0.209*
200	1.06 + 0.152*	0.79 + 0.096*	1.26 + 0.164*	1.63 + 0.221*