Conclusions
An aqueous two-phase system composed of hydrophilic solvent and
an inorganic salt, especially ethanol and ammonium sulfate, is suitable
for the extraction of anthocyanins from V. uliginosum residue. The effect
of ethanol and ammonium sulfate on the partition of anthocyanins was
investigated to obtain the optimum condition for the extraction. The
ATPS composed of 30% (w/w) ethanol/19% (w/w) ammonium sulfate
was found to yield the best result. Meanwhile, the AB-8 resin fit for the
purification of anthocyanins. Compared with conventional extraction
based on acidified ethanol, an integrated process of ATPE combined
with column chromatography has some advantages, such as short
treatment time, lower ethanol consumption and no heating requirement
to yield anthocyanins from the fruit residue of V. uliginosum. This new
technology might be a suitable extraction method for other natural
pigments and bioactive natural products on industrial scale.