Antimicrobial activity of Usnea barbata especially against bacteria involved in pathogenesis of various skin conditions has been well documented in literature. Nevertheless, there are no papers dealing with formulation of its isolates into topical preparations for treatment of skin infections. In present study, alkyl polyglucoside (APG)-based vehicle was developed as carrier of U. barbata CO 2 -supercritical extract (U-SE) that demonstrated the best antimicrobial potential in preliminary screening. For comparison, chosen extract in the same concentration and using the same procedure was incorporated into a pharmacopoeial vehicle. Comparative evaluation of physicochemical stability, efficiency and safety proved APG-based vehicle to possess certain preferential features as carrier of U-SE compared to the reference one, composing a topical formulation with potential clinical relevance in treatment of skin infections.

Recently, research efforts have been directed toward medicinal plants and their extracts, as important sources of natural antioxidant. Lots of biologically active compounds are responsible for the antioxidant effects of yarrow-Achillea millefilium L. extracts. The aim of our study was to determine which of the process parameters of pressure enhanced solvent extraction of Millefolii herba is significant for its efficiency and weather there are interactions between the examined parameters. Compression time, decompression time and the number of cycles were identified as independent variables, while the content of total flavonoids, tannins and total polyphenols were selected as dependent variables. For obtaining the extract of M. herba, rich in antioxidative ingredients, compression time should be set on its higher level (2.0 min), decompression time on its lower level (1.30 min) and the number of cycles on its higher level (99).