Effect of Glycyrrhiza glabra extract on Streptococcus mutans and Candida albicans (in vitro study)

Oral infections and dental caries are still considered as serious public health problems especially in developing countries. It is reported that Glycyrrhiza glabra (G.glabra) extract contains phytomedicine with antibacterial and antifungal properties capable of suppressing oral pathogens associated with plaque forming, caries or fungal diseases. The aim of this study was the assessment of antimicrobial and antifungal activity of aqueous root extract G. glabra on Streptococcus mutans (S.mutans) and Candida albicans (C.albicans).
In this in-vitro experimental study, we evaluated antibacterial and antifungal activity of aqueous root extract of G.glabra (with 93H00l-322herbariyum code) against S.mutans ATCC 35668 and C.albicans ATCC 10231 in the range of 2 to 256 mg/ml by macro- broth dilution method, for determining minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). All of assay was performed in triplicate and the mean of result used for data analysis by SPSS 20 software.
Minimal inhibitory Concentration (MIC) of aqueous root extract of G.glabra were 2 mg/ml for Streptococcus mutans and Minimal Bactericidal Concentration (MBC) were 16 mg/ml. The aqueous root extract of G glabra not only had any antifungal activities against C. albicans in the range of 2-256 mg/ml but also the growth rate increased compared to control group.
It was revealed that although aqueous root extract of G.glabra did not have antifungal effect against C. albicans but also had significant antibacterial activity against S.mutans as a major pathogen of oral hygiene and teeth caries.