Finding the optimal method of extracting propolis with water E. A. Vakhonina 1 *
1 Federal Scientific Center for Beekeeping, Rybnoye, Russia *
E-mail: landych899@gmail.ru Abstract. In the course of the study, an updated database of the content of biologically active substances in aque-
ous extracts of propolis prepared at different temperatures and in different ways is presented.
The purpose of the
work was to select the optimal modes of preparation of aqueous propolis extracts, to determine the content of
biologically active substances in freshly prepared propolis extracts and during storage. The studies were carried
out in the laboratory of the Federal State Budgetary Scientific Institution “FNC of beekeeping”.
The relevance of
the work lies in the development of methods for extracting aqueous extracts of propolis at different temperatures
(
t = 20 °C,
t = 93 °C), the use of ultrasound.
Scientific novelty for the first time biologically active substances were
determined by the method of determining antioxidant activity.
Methods . The yield of extractives (mass fraction of
solids) was determined by drying to constant weight according to GOST 28886-90. Determination of unsaturated
compounds was performed according to GOST 28886-90. The determination of the hydrogen index (pH) was per-
formed according to the Pharmacopoeia (1987) in our modification GOST 28886-90. Determination of flavonoid
and other phenolic compounds was performed by photometry, according to GOST 28886-90 (total flavonoid com-
pounds). Determination of flavan, flavanones, flavonols was carried out according to the method presented in the
“Guidelines for methods of quality control and safety of biologically active food supplements” R 4.1.1672-0, 2004
in terms of routine. The antioxidant activity of propolis aqueous extracts was assessed by a method based on the
reaction of KMnO
4
in the presence of 0.24 M H
2
SO
4
with the studied propolis solution, followed by conversion to
quercetin in 1 ml or 1 g of the drug (patent 2170930).
Results. The amount of solids during storage in the aqueous
extract of propolis (method 1) decreased from 0.23 to 0.15 %; in an aqueous extract prepared using ultrasound
(method 3) increased from 0.21 % to 0.23 %. The amount of solids in propolis aqueous extracts prepared by
methods 2 and 4 decreased during storage from 0.55 to 0.49 % (method 2) and from 0.6 to 0.59 % (method 4).
Keywords: propolis, water extract of propolis, flavonoid compounds, dry matter, pH value, antioxidant activity.