Antioxidant and hepatoprotective effects of silymarin phytosomes compared to milk thistle extract in CCl4 induced hepatotoxicity in rats.

Milk thistle extract is a well-known hepatoprotectant with low bioavailability (20-50%). The objective of the present study is to prepare and characterize silymarin phytosomes and to test the hepatoprotective effect of the phytosomes in CCl4 induced liver injury in rats compared to milk thistle extract. Phytosomes were prepared using lecithin from soybeans and from egg yolk. The prepared phytosomes were examined using scanning electron microscopy, transmission electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy (H(1)NMR). The loading efficiency was >85% in all phytosomal formulations. Formula P2 (with the molar ratio of soybean lecithin to silybin 1:1) and P4 (with the molar ratio of egg-yolk lecithin to silybin 0.25:1) exhibited significantly (p < 0.05) faster release than milk thistle extract. The in vivo study revealed that phytosomes significantly (p < 0.05) decreased glutamic pyruvic transaminase and super oxide dismutase activities compared to milk thistle extract.