Propolis extract – quality analysis and use in semisolid formulations

Abstract

This study aimed to produce propolis liquid and soft extracts, assess quality, and release bioactive compounds in vitro from semisolid formulations with soft propolis extract. Propolis liquid extracts were prepared by maceration method using solvents 40 and 70 % (V/V) ethanol solutions when propolis concentration was 5 and 10 %. Propolis soft extract was produced by evaporation the liquid extract of propolis 10 % was obtained with 70 % ethanol until it became thick consistency. Determination of total phenolic compounds in propolis extracts was performed using the Folin-Ciocalteu reagent and analyzed with a spectrophotometer at 765 nm wavelength. Total phenolic compounds were expressed in p-coumaric acid equivalent. The results showed a trend of a larger total quantity of phenolic compounds with increasing ethanol and propolis concentrations. Research showed that the largest quantity of active compounds was extracted using 70 % ethanol solution as an extranet. Propolis soft extract (3%) was introduced to semisolid pharmaceutical preparations: ointment and w/o cream for assessing the impact of semisolid base on the release of phenolic compounds in vitro. The results show the differences were statistically significant at p < 0.05. A bigger amount of phenolic compounds was released from ointment than from cream. The choice of semisolid base influences the release of phenolic compounds from formulations and the following penetration to the skin.