Antiplanktonic and Antibiofilm Activity of against and .

Periodontitis and peri-implantitis are inflammatory conditions with a high global prevalence. Oral pathogens such as play a crucial role in the development of dysbiotic biofilms associated with both diseases. The aim of our study was to identify plant-derived substances which mainly inhibit the growth of "disease promoting bacteria", by comparing the effect of root extract against and the commensal species . Antiplanktonic activity was determined by measuring optical density and metabolic activity. Antibiofilm activity was quantified using metabolic activity assays and live/dead fluorescence staining combined with confocal laser scanning microscopy. At concentrations of 3.9 mg/L, root extract selectively inhibited planktonic growth of the oral pathogen , while not inhibiting growth of . Selective effects also occurred in mature biofilms, as was significantly more stressed and inhibited than . Our studies show that low concentrations of root extract specifically inhibit growth, and offer a promising approach for the development of a potential topical agent to prevent alterations in the microbiome due to overgrowth of pathogenic .