Acta Pharm. 64 (2014) 173-186


full paper

Original research paper


Antibacterial and quorum sensing regulatory activities of some traditional Eastern-European medicinal plants


1 Department of Microbiology, Orenburg State University, Orenburg, 460018, Russia

2 Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Moscow, Russia

3 All-Russia Research Institute of Beef Cattle Breeding, Orenburg, Russia

Accepted February 13, 2014


The objective of this study was to screen extracts of twenty Eastern European medicinal plants, using wild-type and reporter Chromobacterium violaceum bioassays, for novel components that target bacterial cells and their quorum sensing (QS) communication systems. Three types of activity and their combinations were revealed: (i) direct antimicrobial growth-inhibitory activity, (ii) non-specific and specific pro-QS activities, (iii) anti-QS activity. Among seven plant extracts showing direct growth-inhibitory activity, the strongest effect was shown by Arctostaphylos uva-ursi (bearberry) leaves. Many plants stimulated violacein production by wild-type C. violaceum ATCC 31532 in a non-specific manner, and only the herb Bidens tripartita (three-lobe beggarticks) contained compounds that mimic acyl-homoserine lactone and operated as a QS agonist. Anti-QS activity was found in eleven plants including Quercus robur (oak) cortex, Betula verrucosa (birch) buds and Eucalyptus viminalis (Manna Gum) leaves. Subsequent statistical analysis showed differences between antimicrobial and anti-QS activities, whereas both activities were defined by phylogenetic position of the medicinal resource plant. Finally, extract from Quercus robur cortex revealed at least two fractions, showing different anti-QS mechanisms. These data confirm that multi-component anti-infectious mechanisms are used by plants, which may be useful for drug development.


Keywords: medicinal plants, antimicrobial activity, quorum sensing, Chromobacterium violaceum bioassay