Otimização da extração de própolis verde pela atividade antifúngica e incorporação em biofilme de quitosana

Abstract

The Brazilian propolis market underwent great expansion, leading the propolis processing sector seeks to find the best way to produce propolis extracts with biological activities. With this in mind, this work aimed to optimize propolis extracts for antifungal activity and incorporate the extracts into a chitosan biofilm. The methodology started with the preparation of extracts using ethanol, acetone, ethyl acetate and isopropanol alone and in mixtures of 2 and 3 solvents in equal proportions. The extracts were organized in 3 different designs and had the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) against Candida albicans, Candida tropicalis and Candida glabrata determined by microdilution. From the CIM, the response surface analysis was performed in order to find the extracts in optimal conditions for each planning. Finally, the optimized extracts were incorporated into the production of chitosan biofilms and thickness, water vapor permeation, water solubility and anti-Candida activity in macrodilution were determined. All tested extracts showed antifungal activity for the Candida species tested. The acetone + ethanol extract was highlighted, which promoted the inhibition of yeasts with the lowest values of MIC and CFM (0.76-2.50 mg/mL). In the optimization of the process, the best extracts obtained from each planning were for the mixtures of: acetone + isopropanol; acetone + ethanol and ethyl acetate + isopropanol. The biofilms with incorporated extracts showed no differences in thickness (0.18-0.25 mm), water vapor permeability (11.57-16.96 g/diam²kPa) and water solubility (27 .60-30.44 %) compared to biofilm without extractThe biofilm with acetone + ethanol extract showed the greatest anti Candida activity among the others. Thus, it was confirmed that this is a mixture of good extractive potential for green propolis. Through this work, an optimal extraction condition of biologically active compounds of green propolis was found and the influence of these extracts on the physicochemical characteristics and antifungal activity, when incorporated into the chitosan biofilm, was verified.