Comparison of the antibacterial activity of six medicinal plants, sodium hypochlorite, and chlorhexidine against Enterococcus faecalis (In vitro study)

• Nuha Abdel-Rahman Elmubarak,*  
• Yahia Ibrahim,  
• Abbas Gareeballah,  
• Nada Sanhouri

Abstract

Background: Enterococcus faecalis is gram-positive, facultative anaerobic bacteria. It has been shown resistant to antimicrobial agents. However, some medicinal plants have shown antimicrobial properties against this bacteria. Objectives: To compare the antibacterial effect of six medicinal plants against E. faecalis with sodium hypochlorite and chlorhexidine. Method: Antibacterial susceptibility tests against E. faecalis (ATCC 29212) were performed for 200 mg/ml ethanolic extracts of Acacia Senegal, Capparis decidua, Capparis micracantha, Acacia nilotica/ Adansonia, Dobera glabra , and Moringa oleifera by agar disc diffusion method. Chlorhexidine 0.2% and Sodium hypochlorite 1% were used as positive controls, and ethanol 20% as a negative control. The diameters of the inhibition zones were measured. Results: Acacia nilotica/adansonii leaves showed the largest inhibition zone diameter against E. faecalis. It displayed a significantly greater inhibitory effect against E. faecalis than Acacia Senegal (p-value =0.005), Capparis decidua (p-value =0.02), Capparis micracantha branches (p-value =0.000), Dobera glabra leaves (p-value =0.008), and Moringa olifera leaves (p-value =0.000). Acacia nilotica leaves displayed a similar inhibition zone diameter against E. faecalis as chlorhexidine gluconate 0.2%, but it showed no statistical significance. Acacia nilotica leaves (L) and pods (P), as well as Dobera glabra branches (B), displayed a larger inhibition zone diameter against E. faecalis than Sodium hypochlorite 1%, but with no statistical significance. Conclusion: Acacia nilotica leaves have the strongest antibacterial activity against E. faecalis compared to other plants. It is even surpassing the antibacterial activity of Sodium hypochlorite 1% and has an equivalent antibacterial effect as chlorhexidine 0.2%. Accordingly, Acacia nilotica leaves can be a perfect endodontic irrigant to replace the gold standard.

Keywords

Acacia Senegal, Capparis decidua, Capparis micracantha, Dobera glabra,Chlorhexidine,sodium hypochlorite,Moringa oleifera ,Enterococcus faecalis,Acacia nilotica,Gum Arabic