Figure 1

Flowchart of the isolation process for the ethanol extract of bee pollen. Ethanol extract of bee pollen was subjected to silica gel column chromatography eluted with CHCl₃ and methanol or Sephadex™ LH-20 column chromatography eluted with methanol. Each column chromatography fractions were further purified by repeated ODS or silica gel column chromatography, finally yielding purified 5 compounds.