Phenolic profile and antimicrobial activities to selected microorganisms of some wild medical plant from Slovakia

ObjectiveTo investigate the chemical composition and antimicrobial activity of the methanol extracts of Tussilago farfara (T. farfara), Equisetum arvense, Sambucus nigra (S. nigra) and Aesculus hippocastanum.MethodsThe antimicrobial activities of the extracts against Enterococcus raffinosus, Escherichia coli, Lactobacillus rhamnosus, Pseudomonas aeruginosa, Serratia rubidaea, Saccharomyces cerevisiae and Staphylococcus epidermis were determined by the microbroth dilution method according to Clinical and Laboratory Standards Institute, while the concentrations of main phenolic acids and flavonoids in the form of trimethylsilyl ethers were analysed using gas chromatography-mass spectrometry. The probit analysis was used for statistical evaluation.ResultsOf the 4 plant tested, all extracts showed a significant antimicrobial activity against one or more species of examined microorganisms. The most active antimicrobial plant extract was gathered from T. farfara, followed by Aesculus hippocastanum and Equisetum arvense. The extract from S. nigra showed no antimicrobial effects. The flavonoids quercetin and kaempferol, as well as several phenolic acids (p-hydroxybenzoic acid, gallic acid, ferulic acid and caffeic acid) were identified in all extracts. The highest concentrations of bioactive compounds were detected in the extracts of T. farfara (9 587.6 μg/mg quercetin and 4 875.3 μg/mg caffeic acid) as well as S. nigra (4788.8 μg/mg kaempferol).ConclusionsWe can state that the methanolic plant extract of T. farfara showed the strongest antimicrobial activity against Saccharomyces cerevisiae as well as other tested microorganisms. At the same time, a good antimicrobial activity was found in the other medical plant extracts as well. No antimicrobial effect of the S. nigra extract was found with respect to the growth of Pseudomonas aeruginosa, Enterococcus raffinosus and Saccharomyces cerevisiae.