The content of secondary metabolites and <i>in vitro</i> biological activity of <i>Anchusa officinalis</i> L. (Boraginaceae)

Abstract

In this comparative study, the total phenolic content and flavonoid concentration, as well as free radical scavenging and antimicrobial activity of <i>Anchusa officinalis</i> L. were investigated. Different extracts from above ground flowering plant parts were obtained by extraction using water, methanol, acetone, ethyl acetate and petroleum ether. Highest content of total phenolics, determined spectrophotometrically with Folin-Ciocalteu’s reagent, were recorded in the methanolic extract (116.42 mg GAE/gm of dry extract). The concentration of flavonoids, determined using spectrophotometrically method with aluminum chloride, was highest in acetone extract (146.43 mg RUE/gm of dry extract). The free radical scavenging activity was determined <i>in vitro</i> using DPPH reagent. The greatest antioxidant activity was expressed in methanolic extract (181.85 µg/ml). <i>In vitro</i> antimicrobial activities were determined using a microdilution analysis method – minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. Methanolic extract demonstrated strong antibacterial activity against G-positive <i>Staphylococcus aureus</i> and <i>S. aureus</i> ATCC 25923 with MIC values below 0.156 mg/ml. Based on the results, <i>A. officinalis</i> can be regarded as promising plant source with high value of biologically active compounds.