Element composition of propolis tinctures prepared from Hungarian raw propolis

Abstract

Although the element composition of raw propolis gets more and more attention, their products, like tincture are barely analyzed. In this study the element content of tinctures prepared by 80% (v/v) ethanol is measured parallel to the initial raw propolis. Most of the essential elements had relatively high transfer coefficients to the tincture in the range of 14.2–67.3% by median. In contrast, most of the potentially toxic elements (Al, Ba, Cd, Cs, Sr, V) had transferred at a rate usually below 10%. Transfer coefficients of Ni and Cr were the highest: 7.02–62.6% and 1.20–30.4%, respectively. When considering the consumption of tinctures, potentially toxic elements are taken into the body in just a nanogram per day magnitude or less. The quantity of bioactive compounds in tincture are higher in several orders of magnitude, than potentially toxic elements. Nevertheless, raw propolis containing a high concentration of potentially toxic elements, especially Ni and Cr, is to be avoided. The transfer coefficient was applied for the prediction of the mineral composition in raw propolis due to the mineral content of tincture. Generally, even an overestimation by two or an equal level of underestimation should be expected, even if the same extraction process was used.