Antibiofilm effect of Drosera rotundifolia against uropathogenic E. coli strains

Urinary tract infections (UTI), often caused by uropathogenic E . coli , are the most common bacterial infections worldwide [ 1 ]. The increasing prevalence of multidrug-resistant pathogens and their ability to form biofilms make effective treatment difficult and contribute to recurring infections [ 2 ]. Although herbal medicines such as bearberry leaves are already used in UTI therapy [ 3 ], there is still a need for innovative treatment. Drosera rotundifolia , a carnivorous plant and traditionally used for respiratory ailments, contains antibacterial naphthoquinones and flavonoids with spasmolytic properties [ 4 ] [ 5 ]. In this study, crude extracts, fractions, and isolated compounds were tested in a bioactivity-guided approach for their efficacy against uropathogenic E . coli strains. To gain deeper insights into the underlying mechanisms of the observed anti-biofilm activity, proteomic analyses were carried out. The data showed that treatment with Drosera rotundifolia led to an increased abundance of proteins involved in iron uptake, suggesting that the plant extract may induce iron stress in bacteria. Iron is an essential element for both bacterial metabolism and virulence. Interfering with iron-dependent mechanisms may therefore represent a promising approach to weaken bacterial persistence and pathogenicity.This effect may be attributed to the ability of the plant’s flavonoids to chelate iron. The iron-binding capacity of Drosera rotundifolia flavonoids was confirmed using a Chrome Azurol S assay. Consequently, the inhibition of iron metabolism by flavonoids may play a crucial role in reducing biofilm formation. These findings highlight the potential of Drosera rotundifolia as a source of antivirulence agents and offers an innovative approach for the treatment of uncomplicated, recurrent urinary tract infections. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany