Counter-current chromatography has

Counter-current chromatography has a number of key
advantages in the purification of natural products. For
example, the solvent usage is generally far lower than
that of solid phase chromatography systems operating
at the same scale (about 25 %) (Graham et al. 2001).
Furthermore, since the process is frequently an
isocratic one, a simple analysis of solvent composition
allows the recycling of the solvents, reducing the
usage still further (Garrard et al. 2007). The technique
also allows for 100 % recovery of the sample components.
In other words, the target compound can always
be retrieved since there is no solid phase and therefore
no possibility of losses arising from irreversible
adsorption onto the solid matrix. This is a significant
advantage in every purification process. As a solidfree
and therefore relatively gentle chromatographic
technique, CCC can be used for the isolation of
unstable natural compounds. Baldermann et al. (2007)presented the successful purification of 90
-cis-neoxanthin,
the predominant isomer of neoxanthin in green
vegetables. Major problems during its isolation
include isomerization and oxidation, mainly caused
by higher temperatures, light or oxygen exposure.
When typical solid stationary phase techniques are
applied, the rearrangement products can be detected or
complete isomerization can be observed. A solid-free
technique is a very practical solution for avoiding the
above mentioned complications.