Evaluation of silymarin extraction from Silybum marianum (L.) Gaertn seeds by water

The seeds extract of Silybum marianum (L.) Gaertn is named silymarin and used in treatment of liver diseases, diabetes (II) and hypercholesterolemia. There are different solvents (methanol, ethanol, acetonitrile and acetone) for extraction of this compound. Water is an inetersting alternative because of its low operating and disposal costs. This study was undertaken to evaluate the efficiency of different methods on silymarin production and followed by HPLC analysis of extracted flavonolignans. The highest content of taxifolin, silychristin and silydianin were 0.63, 0.9 and 2.35 mg g-1 DW, respectively in a soxhlet extraction with water for 12 h after a pre-treatment step involving defatting with petroleum ether. The highest content of silybin and isosilybin were extracted 0.24 and 0.15 mg g-1 DW in a soxhlet extraction with water without defatting process. Although the ratio of the extracted componds with water were less than methanolic extraction, for increasing the quality of the products, the water extraction steps should be well studied both in terms of time and methods.