Abstract
Salvia officinalis L. and Plantago lanceolata L. are plants found in Romania's natural flora. They have been used for a long time in folk medicine due to their beneficial properties based upon their phenolic compound content. This study compared these hydroalcoholic extracts of these plants separately and in a 1:1 mixture and determined the concentration of several compounds that possess antioxidant properties. Nine phenolic compounds, including (+)-catechin, syringic acid, cinnamic acid, resveratrol, chlorogenic acid, caffeic acid, ferulic acid, rutin and quercetin, were determined by use of an optimized high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method. The aim of the study was to validate this method and to highlight the benefits of the mixture of extracts. The total concentration of phenolic compounds determined for S. officinalis L. was five times larger than for P. lanceolata L. In the extract of P. lanceolata L. several compounds, such as (+)- catechin and chlorogenic acid were not detected, while the extract of S. officinalis L. had all of the analyzed compounds. Even though the analyzed compounds were found in both plant species, the mixture of extracts showed an increased concentration of these compounds, thus enriching qualitative and quantitative properties of the resulting extract in comparison to the individual isolates. The analyzed extracts may be used for their health benefits due to the above-mentioned compounds that possess antioxidant properties.