Russian Journal of Applied Chemistry, 2013, Vol. 86, No. 6, pp. 905−908.
Pleiades Publishing, Ltd., 2013.
Original Russian Text © T.S. Lozovskaya, V.M. Bolotov, 2013, published in Zhurnal Prikladnoi Khimii, 2013, Vol. 86, No. 6, pp. 963−966.
Concentration of Anthocyanin Pigments from Aqueous
Extract with M-PVA Sorbent
T. S. Lozovskaya and V. M. Bolotov
Voronezh State University of Engineering Technologies, Voronezh, Russia
Received January 28, 2013
Abstract—M-PVA magnetic sorbent was applied for the ﬁ rst time to recovering concentrate of anthocyanin pig-
ments from aqueous extract. М-РVA was separated from the sorption medium under the action of external magnetic
ﬁ eld. Desorption with 96% ethanol yielded a solution in which the concentration of the pigments was three times
higher than in the initial extract. The concentrate recovery takes 15 min. М-PVA sorbent can be repeatedly used
for recovering desired molecules from a medium containing particles of vegetable material.
Natural and synthetic dyes are used for imparting
attractive appearance to foodstuffs. Various tints of red
can be achieved with anthocyanin dye (Е163) of plant
origin. In addition, this dye exhibits a wide spectrum of
therapeutic properties [1, 2]. The list of natural sources
of anthocyanins is very large and includes the majority
of colored cultivated plants, berries, and fruits [3, 4].
Pigments are commonly recovered from plant raw
materials by extraction with aqueous and aqueous-
ethanol HCl solutions containing no more than 1%
acid . The subsequent step consists in separation of
the plant raw material from the extract by ﬁ ltration.
The recovered extract contains a large amount of the
solvent. It is removed by thermal concentration, actually
consisting in water evaporation from the extract.
However, in many cases the action of high temperatures
leads to the loss of color due to decomposition of the
principal component, anthocyanin, and to numerous
reactions between other components of the extract with
the formation of colored compounds .
An alternative approach to the isolation and
concentration of substances unstable at high temperatures
is based on adsorption technologies. Procedures for
isolating anthocyanins by methods based on preparative
chromatography have been reported , but they have
not yet found wide use for obtaining large amounts of
the product. Therefore, search for new approaches and
new sorbents is still topical.
One of new approaches to concentration of
substances from solutions is based on using sorbent
particles consisting of a sorbing layer and a magnetic
core [8, 9]. The presence of the magnetic core in the
sorbent particle allows its localization in solution to be
controlled by applying external magnetic ﬁ eld, which
creates prerequisites for automation of the concentration
This study deals with concentration of anthocyanin
pigments from aqueous extract using M-PVA magnetic
Na, KCl, and HCl (36 wt %) (Merck) were
of analytically pure or HPLC grade.
For magnetic recovery of anthocyanins, we used
M-PVA magnetic particles 1–3 μm in diameter
(Chemagen Biopolymer Technologie AG, Germany),
containing 50–60% magnetite coated with a layer of
polyvinyl alcohol. The adsorbent was used as aqueous
suspension containing 50 mg mL
The adsorbent was separated from the liquid phase
under the action of external magnetic ﬁ eld. Under the