Objective: In this study, it is aimed to investigate the antimicrobial potential of the dietary phytochemicals including quercetin, curcumin, apigenin, pyrogallol, gallic acid, luteolin and hydroxytyrosol against the periodontal pathogenic bacteria including Porphyromonas gingivalis ATCC 33277, Prevotella intermedia ATCC 25611 and Aggregatibacter actinomycetemcomitans ATCC 43718.

Material and Methods: The antimicrobial potential of the dietary phytochemicals was investigated by using agar well diffusion and microdilution methods. The antimicrobial activities of the phytochemicals were both studied at a concentration of 3 mg/ml and also in concentrations of 3, 1.5, 0.75, 0.375, 0.187, 0.093, 0.046, 0.023 and 0.011 mg/ml using microdilution methods, respectively. Amoxicillin (20 μg/disc, 0.04-0.0015 mg/ml) and DMSO (≤10%) were tested as positive and negative controls, respectively.

Results: According to the results of this study, most of the phytochemicals had antimicrobial activity aganist all of the bacteria. The most effective phytochemical against pathogens was quercetin. The phytochemicals with the strongest antimicrobial potential were determined as quercetin, curcumin, luteolin, apigenin and gallic acid. In our study DMSO (≤4%, v/v) showed no antimicrobial effect on the pathogens.

Conclusion: In addition to the usage of antibiotics in the treatment of periodontal diseases, the consumption of the phytochemicals including especially curcumin, quercetin, luteolin, gallic acid and apigenin may be appropriate and helpful. Therefore, it is suggested that more detailed in vivo research about the inhibition mechanisms of the periodontal pathogens by potent phytochemicals should be performed and, further in vivo studies should be carried out to detect effective usage of these phytochemicals.