Lollipop containing Glycyrrhiza uralensis extract reduces Streptococcus mutans colonization and maintains oral microbial diversity in Chinese preschool children

Abstract

The anticariogenic activity of the extract of Glycyrrhiza uralensis (licorice) has been well documented. We recently developed an herbal lollipop containing licorice extracts with Glycyrrhizol A, the compound displaying strong antimicrobial activity against Streptococcus mutans . Preliminary testing showed that the herbal lollipop reduced salivary S . mutans counts in vivo . In this study, we aimed to further test the efficacy of this herbal lollipop for reducing salivary S . mutans levels, and investigate its impact on salivary microbiome. Using a well-established in vitro oral microbiome model, we showed that licorice extract displays targeted killing against S . mutans without affecting the biodiversity of the community. In vivo study corroborated in vitro findings, showing for high caries-risk children aged 3–6 with salivary S . mutans levels >5x10 5 cells/ml, daily use of 2 licorice-containing lollipops for 3 weeks significantly reduced salivary S . mutans levels compared to the control group. Salivary microbiome analysis showed either no change or even increase in phylogenetic diversity of the oral community following herbal lollipop usage. Although further study with longer term observation is needed, these results suggest that use of licorice extract-containing lollipops can be as a simple and effective way to reduce the risk of dental caries in children.

Antimicrobial Effects against Oral Pathogens and Cytotoxicity of Glycyrrhiza uralensis Extract

“…Glycyrrhiza uralensis Fisch, commonly known as Chinese licorice root, is one of the most popular natural products used in traditional medicines, and its chemical constituents and biological activities have been examined in clinical settings [ 10 , 11 , 12 ]. The compound glycyrrhizol A, present in the ethanolic extract from G. uralensis , has high antibacterial activity against S. mutans , and flavonoids in G. uralensis inhibit the activity of oral pathogens [ 12 , 13 , 14 ]. Although components of G. uralensis have been explored as antimicrobial agents, the use of G. uralensis extracts to prevent or treat oral infections, and the biocompatibility of this plant for application in oral hygiene materials, have not yet been examined.…”

The potential of glycyrrhizin and licorice extract in combating COVID-19 and associated conditions

“…In comparison between the efficacy of licorice and propolis extract used as anticavity against Streptococcus mutants , licorice extract exhibited better antibacterial efficacy ( Godbole et al, 2019 ). Licorice-containing lollipops were effective in reducing significantly salivary S. mutants in high caries-risk children aged 3–6 and decrease significantly the risk of dental caries in children ( Chen et al, 2019 ). Also, in twenty patients aged between 18 and 21 years, licorice lollipop was effective in suppressing S. mutans and dental caries ( Krishnakumar et al, 2018 ).…”

The Research Updates and Prospects of Herbal Hard-Boiled Lozenges: A Classical Platform With Promising Drug Delivery Potential

“…It acts through its antimicrobial effects on cariogenic bacteria Streptococcus mutans. This herbal lollipop could be a novel tool to promote oral health through functional foods [58][59][60][61]. Lozenges have been developed consisting of extracts of spices, ginger and garlic.…”