Separation of Silymarins from Milk Thistle (Silybum Marianum L.) Extracted with Pressurized Hot Water using Fast Centrifugal Partition Chromatography

Abstract

Fast centrifugal partition chromatography was used to separate a class of flavonolignans called silymarins from both a purchased silymarin powder and a crude pressurized hot water extract of milk thistle (Silybum marianum L.). Initially, a purchased power of a mixture of the six silymarin compounds was separated with a two-phase solvent system consisting of heptane/ethyl acetate/methanol/water (1:4:3:4 v/v/v/v) in order to verify elution times of the compounds by fast centrifugal partition chromatography. Next, a crude pressurized hot water extract from 10 g of ground seeds of Silybum marianum was separated with the same solvent system. The separation from the hot water extract gave yields of silychristin at 70.2% purity, silydianin at 93.7% purity, and a mixture of silybinin and isosilybinin at 96.1% purity.