Characterization of gingerol analogues in supercritical carbon dioxide (SC CO2) extract of ginger (Zingiber officinale, R.,).

Organically grown ginger rhizome (Zingiber officinale
Roscoe) SC CO2 extract obtained at 280 bar and 40 °C
and its column chromatographic fractions are characterised for
its composition. The components in the extract and fractions
are identified by HPLC and LC based MS and are used as
standard for the estimation of gingerol analogues in the extract.
HPLC and mass analysis of the extracts confirmed the
various forms of gingerol constituents [4]-, [6]-, [10]-gingerols
and [6]-, [8]-, [10]-shogaols in ginger extracts. SC CO2
extract of organic ginger was found to show 6-gingerol around
25.97 % of total extract. The estimation of [6]-gingerol, [6]-
shogaols, [4]gingerol, [10]-gingerol and 6-gingediol content
of the SC CO2 purified ginger extract was found to be 75.92±
1.14, 1.25±0.04, 4.54±0.04, 13.15±0.30 and 0.37±0.00 %
respectively. Antioxidant activity was measured by 2, 2-
diphenyl-1-pycryl-hydrazyl (DPPH) free radical scavenging
and ferric reducing antioxidant power (FRAP) and the assay
have shown 652±0.37 mg TE/g and 3.68±0.18 mg TE/100 g
respectively, are significantly higher results with SC CO2
organic ginger extract. Paradol analogues are not detected
in this study. Small quantities of [4]-, [10]gingediol and
[6]-gingediacetate are also found in ginger extract.