NAC and taurolidine were effective against E. faecalis in planktonic state, at the expense of demonstrating cytotoxic effects. For both planktonic and biofilm forms of E. faecalis, neither NAC nor taurolidine offered any advantage over CH.

Objective: In this study it was aimed to examine antiquorum sensing, antioxidant activities by using root and aerial parts extracts of Tragopogon oligolepis. Also phenolic content was detected using HPLC analysis.Material-Method: Antioxidant activity was detected by DPPH, FRAP methods and phenolic content HPLC. Antiquorum sensing activity was investigated by using pyocyanin and swarming motility assay on Pseudomonas aeruginosa PAO1. Results: Phytochemical profile findings showed that 12 components were detected in the root and 10 components in the aerial parts. The main components were found chlorogenic acid and o-coumaric acid. According to the obtained of antioxidant levels the aerial parts extracts of T. oligolepis had the best antioxidant property in our results. The amount of DPPH (0.60 ± 0.01 mg/ml) and phenolic content (6.55±0.18 mg GAE/g sample) was determined to be high in the aerial parts. In the FRAP analysis, high reducing power was found in the roots (12.62±0.36 μmol FeSO4/g sample). According to these results, although T. oligolepis extracts do not reach very high amounts in terms of antioxidant results, it is thought to be a plant that can be evaluated in terms of removing oxidant effects. The results of antiquorum sensing activity showed that both root and aerial parts extract showed strong inhibitory effect on swarming motility 62%, %65 rate respectively.Conclusions: Tragopogon oligolepis, an endemic species, can be evaluated as an antiquorum sensing inhibitor candidate with its phytochemical contents.