The invention relates to a method for extracting and purifying 6-
gingerol from ginger, which comprises the following steps: (1) extraction and concentration of
gingerol: heating sliced ginger in
ethanol under
reflux, and concentrating to obtain a
ginger extract; (2) leaching of
gingerol: leaching the
ginger extract to obtain a leaching solution, and recycling the extract under reduced pressure to obtain a gingerol crude extract; (3)
silica gel column chromatography: dissolving the gingerol crude extract in
ethyl acetate, adding
silica gel, mixing, and after the
solvent is volatilized, passing through a
silica gel column by a dry process; after carrying out
isocratic elution and thin-layer
chromatography (TLC) detection, collecting the eluate part containing 6-gingerol, recycling the eluate under reduced pressure to obtain a 6-gingerol crude product; passing the 6-gingerol crude product through the silica gel column, and carrying out
elution, detection, collection and
solvent recycling to obtain the higher-purity 6-gingerol; and (4) purification by
preparative HPLC (
high performance liquid chromatography): dissolving the higher-purity 6-gingerol, purifying by
preparative HPLC, carrying out
isocratic elution, collecting the part with the maximum chromatogram peak, and
drying by
distillation to constant weight, thereby obtaining the high-purity 6-gingerol. The technique is simple and easy to operate; and the product has the advantages of high yield and good quality.