Planta Med 2015; 81 - PM_12
DOI: 10.1055/s-0035-1565389

Antibacterial activity of Rumex aquaticus and R. thyrsiflorus extracts and isolation of the biologically active compounds

O Orbán-Gyapai 1, E Liktor-Busa 1, E Urbán 2, N Kúsz 1, G Jakab 3, D Stefkó 1, J Hohmann 1, A Vasas 1
  • 1Department of Pharmacognosy, University of Szeged, Szeged, Hungary
  • 2Institute of Clinical Microbiology, University of Szeged, Szeged, Hungary
  • 3Institute of Environmental Sciences, Faculty of Water and Environmental Management, Szent István University, Szarvas, Hungary

Nosocomial infection became a major problem not only in hospitals, but worldwide as it can cause endemic diseases. The uncontrolled usage of antibiotics led to the increased number of resistant bacteria strains. The aim of our study was to find new compounds from plants with potential antibacterial properties on several resistant strains.

The members of the genus Rumex (family Polygonaceae), which are distributed worldwide, comprise approximately 200 species. Previously, anthraquinones, naphthalenes, flavonoids, stilbenoids, triterpenes, carotenoids and phenolic acids have been isolated from Rumex species. The extracts of these plants, and compounds isolated from them, have been demonstrated to possess various pharmacological activities, including anti-inflammatory, antioxidant, antitumour and antimicrobial properties.

We have investigated the antimicrobial potency of the aerial parts and roots of two Rumex species, R. aquaticus and R. thyrsiflorus against different bacterial strains (methicillin-resistant Staphylococcus aureus, S. aureus, Staphylococcus epidermidis, Moraxella catarrhalis, Streptococcus pneumoniae, S. pyogenes and Bacillus subtilis) with disc-diffusion method. The ethyl-acetate fraction of the aerial parts of R. aquaticus and the roots of R. thyrsiflorus and the n-hexane, chloroform and ethyl-acetate fractions of the roots of R. aquaticus possessed remarkable antimicrobial effects. With the combination of different chromatographic methods 14 compounds, among them flavonoids (quercetin- and kaempferol-glycosides, epicatechin, procyanidin B5), anthranoids (chrysophanol, emodin, torachryson-glucoside, citreorosein), naphtalenes (musizine- and nepodine-glucoside) and a monoacyl-glycerol were isolated, some of them responsible for the pharmacological activity.

Acknowledgement: This work was supported by the Hungarian Scientific Research Fund (OTKA PD101432) and a János Bolyai Research Scholarship of the Hungarian Academy of Sciences.