Antimicrobial Effects against Oral Pathogens and Cytotoxicity of Glycyrrhiza uralensis Extract

Abstract

<jats:p>We aimed to evaluate the antimicrobial effects of Glycyrrhiza uralensis extract on Streptococcus mutans and Candida albicans and its biocompatibility for dental applications. The antimicrobial activity of the G. uralensis extracts at concentrations of 50, 100, 150, and 200 µg/mL was assessed using agar disk diffusion tests, counting the total number of colony-forming units (CFUs), spectrophotometric growth inhibitory assays, and microbial morphology observations using scanning electron microscopy (SEM; Merin, Carl Zeiss, Oberkochen, Germany). We measured the polyphenol and flavonoid contents of G. uralensis extracts using ultraviolet–visible spectrometry and the cytotoxicity of these extracts using an MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. We identified that G. uralensis extracts had significant antimicrobial effects against S. mutans and C. albicans. The optical density of the experimental groups significantly decreased compared with that of the control group. SEM images revealed that the G. uralensis extract affected the morphology and density of S. mutans and C. albicans. The extract concentration of flavonoids, but not polyphenols, increased with increasing concentrations of the G. uralensis extract. Furthermore, cell viabilities were more than 70% for G. uralensis extracts with concentrations of 50 and 100 μg/mL. Naturally derived G. uralensis is biocompatible and exhibits an excellent antimicrobial effect against oral pathogens such as S. mutans and C. albicans. Thus, G. uralensis extracts can be used for the development of oral products that treat and prevent oral diseases.</jats:p>

A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of a Mouthwash Containing Glycyrrhiza uralensis Extract for Preventing Dental Caries

“…It was confirmed that the detection of A. viscosus in the mandible decreased immediately after using mouthwash containing Glycyrrhiza uralensis and at 5 days after use. These results are consistent with the in vitro studies that have already confirmed the antibacterial effect of Glycyrrhiza uralensis on the bacteria that cause dental caries [ 32 , 33 , 34 ].…”

“…The Glycyrrhiza uralensis extract exhibited excellent antimicrobial effects against S. mutans . Thus, the Glycyrrhiza uralensis extract at a concentration of 100 μg/mL was considered a biocompatible, naturally derived extract [ 32 ]. Specifically, licoricidin, licorisoflavan A, licorisoflavan C, licorisoflavan D, licorisoflavan E, and Glycyrrhizol A have been reported to inhibit effectively [ 33 ].…”

Surface Characterization, Biocompatibility and Antifungal Efficacy of a Denture-Lining Material Containing Cnidium officinale Extracts

“…Previous studies have attributed the antifungal properties of CO to phenolic compounds, which are reference substances that exhibit antibacterial activity in natural extracts [ 13 ]. Furthermore, studies have reported on the antibacterial properties of phenolic compounds, such as polyphenol and flavonoids, against C. albicans [ 12 , 25 ]. The antioxidant activity and effect of the phenolic component of CO were confirmed by previous studies, along with its antibacterial activity against Streptococcus mutans and C. albicans , which are two major oral pathogens [ 21 , 26 ].…”

“…Recently, several studies have devoted considerable effort to investigating natural products, with antibacterial properties and few side effects, to develop dental materials containing natural antibacterial substances [ 7 , 12 ]. Among the natural alternatives, Cnidium officinale (CO), a perennial herb belonging to the umbel family, has been reported to possess excellent antibacterial, antifungal, sedative anti-inflammatory, and analgesic properties [ 13 , 14 , 15 ].…”

Surface Characterization, Antimicrobial Activity, and Biocompatibility of Autopolymerizing Acrylic Resins Coated with Reynoutria elliptica Extract

“…The application of natural medicines is an effective and safe approach to inhibit the microbial activity of oral pathogens [ 37 , 38 , 39 , 40 ]. Reynoutria elliptica is a perennial plant of the Polygonaceae family that effectively treats diuretic and menstrual disorders, promoting blood circulation, alleviating pain, and relieving respiratory diseases [ 41 ].…”