Research of Nonea rossica bioactive compounds and estimation of an antibacterial activity of extracts made from it
Nonea rossica Steven. (Boraginaceae) is used in folk medicine as an anti-inflammatory and an antibacterial remedy. The aim of this work was to investigate bioactive compounds of aerial parts of N. rossica gathered in the flowering stage and also to estimate the antibacterial activity of its total extract. The qualitative composition and quantitative content of the following chemical constituents was determined by TLC, spectrophotometry and chromatography-mass spectrometry with standard samples: tannins –9,7%, anthocyanidins –1,1%, water-soluble polysaccharides and pectin –7,1%, steroid saponins –0,12%. The in vitro antimicrobial activity of the extract was evaluated. The extract from aerial parts of the plant was prepared using 40% ethanol as the extractive solvent (ratio of raw material: extractant –1: 50). The antibacterial properties of these extracts were investigated against Staphylococcus aureus. First the plant extracts were added to the nutrient medium, followed by bacterial inoculation (S. aureus strain MR, ATCC 35591). It could be established that the initial extract showed antibacterial activity (MIC) against this strain until a dilution of 1:10 with water. Most probably, steroid saponins are responsible for the established antibacterial activity of the extract.