Evaluation of the Antimicrobial Efficacy of Ethanolic and Aqueous Extracts of Licorice (Glycyrrhiza glabra) Against a Periodontal Pathogen: An In Vitro Study

Background: Periodontal disease is a major contributing factor to tooth loss and can significantly impact overall health. Traditional periodontal therapy typically involves mechanical debridement to remove plaque and calculus, along with the use of antimicrobial agents to reduce bacterial load. Licorice (Glycyrrhiza glabra) has a long history of use in traditional medicine for treating various ailments since it contains glycyrrhizin, glabridin, liquiritin, and flavonoids, which possess anti-inflammatory, antioxidant, and antimicrobial activities. Hence, licorice can be considered a viable alternative for managing periodontal inflammation.

Aim: The objective of this study is to conduct a comparative evaluation of the antimicrobial efficacy of ethanolic and aqueous extracts of licorice (Glycyrrhiza glabra) against a key periodontal pathogen, Prevotella intermedia (P. intermedia) Methodology: In this study, aqueous and ethanolic preparation of licorice was done, and the antimicrobial effect of these extracts against P. intermediawas tested by evaluating the minimum inhibitory concentration (MIC). The gold standard chemical plaque control agent chlorhexidine was used as a control. Result: Results of the present study showed that licorice extract has antimicrobial activity against P. intermedia. The MIC of aqueous and ethanolic licorice root extracts against P. intermedia was established at 0.8% and 0.1%, respectively. When the aqueous and ethanolic extracts were compared, the ethanolic extract of licorice showed significantly more antimicrobial properties than the aqueous extract.

Conclusion: Ethanolic extract of licorice possesses highly significant antibacterial activity against P. intermedia; hence, it can be used as an alternative to chlorhexidine mouthwash.