Evaluation of variability of silymarin complex in Silybi mariani fructus harvested during two production years

Milk thistle [Silybum marianum (L.) Gaertn.], a member of Asteraceae family, is one of the most cultivated medicinal plants widespread throughout the world. The pharmacological drug is a ripe fruit without pappus – Silybi mariani fructus – containing flavonolignans and generating silymarin complex. In folk medicine, it is used for the treatment of liver disorders, kidney problems, rheumatism as well as gastronomic disturbances, cardiac and neurotic disorders, and fever. The components of silymarin complex are useful in cancer prevention and treatment. The aim of the study was to determine the amount of silymarin complex contained in the fruit of the harvest of two consecutive years and how much they differ from one another. Representative samples of fruit were collected in 2015 and 2016 and distributed by a company Agrofos (Slovakia). Regarding the analytical method, we used a high-performance liquid chromatography (HPLC); the method was approved by the European Pharmacopoeia 10. The statistical significance was on the level P < 0.05. The total content of silymarin complex was 15.28 ± 0.06 g.kg⁻¹ (in 2015) and 16.65 ± 0.09 g.kg⁻¹ (in 2016). In both studied years, the highest representation of silybin B was observed (7.04 ± 0.07 g.kg⁻¹ versus 5.92 ± 0.08 g.kg⁻¹). The differences between the individual fractions of the silymarin complex were statistically significant. There was also a significant difference of 9% in the total silymarin content between 2015 and 2016. In conclusion, we can state that both samples of Silybi mariani fructus meet the requirements of the European Pharmacopoeia.