Moringa oleifera L. and red pomegranate extracts have been reported to inhibit gram-positive facultative anaerobe growth and inhibit the formation of biofilm on tooth surfaces. The current study aimed to assess the antibacterial effect of M. oleifera L. and red pomegranate extracts and their combinations against Porphyromonas gingivalis. The antimicrobial sensitivity, minimum inhibition concentrations (MIC), and minimum bactericidal concentrations after treatment with the aqueous extracts of M. oleifera L. and red pomegranate as well as their combination against clinically isolated P. gingivalis were determined using agar well diffusion and two-fold serial dilution. The anti-biofilm activity of the extracts and their combination was evaluated using the tube adhesion method. The phytochemical analysis was carried out using gas chromatography-mass spectrometry. It was found that P. gingivalis was sensitive to aqueous extract of M. oleifera L. seeds and red pomegranate albedo, however, not to M. oleifera L. leaves and red pomegranate seeds. The MIC value of M. oleifera L. seeds, red pomegranate albedo, and their combination were obtained at 12.5 mg/ml, 6.25 mg/ml, and 3.12 mg/ml against P. gingivalis, respectively. The extract combination had the highest anti-biofilm effect than M. oleifera L. seeds and red pomegranate albedo aqueous extracts at the minimum concentrations of 6.25 mg/ml, 25 mg/ml, and 12.5 mg/ml, respectively. The combination of red pomegranate albedo and M. oleifera L. seeds showed superior antibacterial and anti-biofilm effects against P. gingivalis, followed by red pomegranate albedo and M. oleifera L. seeds. This may highlight a promising alternative to the traditional chemicals that can be used as an adjunct in the treatment of periodontal diseases.
