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, antiinflammatory 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 antitumor 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 HP20 resin, silica gel and Sephadex LH20 as stationary phase, respectively. 1HNMR and 13CNMR techniques were used to identify these compounds. Finally, the HPLC method has been used to standardize. Results: 1HNMR and 13CNMR 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.