Purification, identification, and standardization of silybin A & B composition from Silybum marianum (L.) Gaertn.

Background: Silybum marianum (L.) Gaertn. (Milk thistle) is a perennial herb with medicinal properties. The seeds of these plants contain silymarin compounds with flavonolignan structure and antioxidant, anti-inflammatory and hepatoprotective effects. The major bioactive constituent of S. marianum is silybin A and B. It is used in the treatment of various liver conditions and exhibits high anti-tumor promoting activity. Objective: The purpose of this study was to purify, identify, and standardize of silybin A and B from the seeds extract of Silybum marianum . Methods: At first, the milk thistle seeds were defatted with hexane and then extracted with methanol as solvent. Isolation and further purification of silybin A and B was carried out by column chromatography using Diaion HP-20 resin, silica gel and Sephadex LH-20 as stationary phase, respectively. 1 H-NMR and 13 C-NMR techniques were used to identify these compounds. Finally, the HPLC method has been used to standardize. Results: 1 H-NMR and 13 C-NMR techniques characterized the structure of silybin A and B extracted from Silybum marianum L. and standardization and determination of their purity was performed using HPLC. Conclusion: Our proposed system presented significant advantages in increasing efficiency and reducing cost, and the diastereoisomers of silybin A and silybin B in silymarin were successfully isolated with high purities.