Antimicrobial Effect of a Peptide Containing Novel Oral Spray on Streptococcus mutans

Abstract

Objective. To investigate the antibacterial effect of a novel antimicrobial peptide containing oral spray GERM CLEAN on Streptococcus mutans (S. mutans) in vitro and further explore the related mechanisms at phenotypic and transcriptional levels. Methods. The disk diffusion method was used to preliminarily appraise the antimicrobial effect of GERM CLEAN. The minimal inhibitory concentration (MIC) of GREM CLEAN towards S. mutans was determined by the broth dilution method. S. mutans virulence-related phenotypic assays including initial adhesive assay, pH drop, exopolysaccharides (EPS), and biofilm formation measurements and quantitative real-time PCR (qRT-PCR) were further applied to detect the inhibitory mechanisms of GREM CLEAN at 1/2MIC. Results. The diameter (10.18 ± 1.744 mm) of inhibition zones formed by GERM CLEAN preliminarily indicated its inhibitory effect on the major cariogenic bacteria S. mutans. The minimal inhibitory concentration of GERM CLEAN on S. mutans was 100% mass fraction (the stock solution). The study of the antibacterial mechanism showed that GERM CLEAN had a certain inhibitory effect on the initial adhesion, acid production, extracellular polysaccharides (EPS) production, and biofilm formation of S. mutans. GERM CLEAN disturbed S. mutans biofilm physiology mainly through destruction of biofilm architecture and suppression of bacterial growth. The results of qRT-PCR further confirmed that the expression levels of EPS and lactic acid generation genes including gtfB, gtfC, gtfD, and ldh were significantly repressed by treating with GERM CLEAN, and this was consistent with our phenotypic results. Conclusion. The novel antimicrobial peptide containing oral spray GERM CLEAN has an anti-Streptococcus mutans effect and the inhibitory property may be due to suppression of the virulence factors of S. mutans including adhesive, acidogenicity, EPS, and biofilm formation.

Synthesis of silver nanoparticles using gum Arabic: Evaluation of its inhibitory action on Streptococcus mutans causing dental caries and endocarditis

“…The gyra A gene studied is also an important virulent gene of S. mutans. The DNA gyrase encoding gyra A is a housekeeping gene offers protection to S.mutans against antibiotics and environmental stress [ 38 , 39 ]. In the present study, the synthesized GA-AgNPs inhibited the virulence of gyra Agene.…”

Anticaries activity of GERM CLEAN in Streptococcus mutans and Candida albicans dual‐species biofilm

“…mutans is 100% mass fraction and 1/2 MIC GERM CLEAN decreased EPS production, biofilm formation, acidogenicity, and related gene expression of S. mutans (Xiong et al, 2020). In this study, we further analyzed the effects of GERM CLEAN with same concentration on S. mutans and C. albicans dual-species biofilm and evaluated whether it affected the bovine enamel demineralization.…”

“…The suspension of each microorganism was diluted to OD 600nm = 0.5 with YNBB for the subsequent assays. In our previous study, we have found that the MIC of GERM CLEAN on S. mutans was 100% mass fraction (stock solution) and that GERM CLEAN of its 1/2 MIC (50% mass fraction) showed antibacterial effect on S. mutans in vitro (Xiong et al., 2020). In this study, we aimed to further evaluate the effect of GERM CLEAN with the same mass fraction on dual‐species microorganisms of S. mutans and C. albicans in vitro.…”

“…GERM CLEAN is a novel oral spray produced by Chengdu Scisyn Pharmaceuticals Co., Ltd which is mainly composed of a newly synthetic polypeptide. Our previous study has proved its antibacterial properties on S. mutans which implied its promising function in caries prevention and treatment (Xiong et al., 2020). The mild, colorless, and nearly non‐stimulating nature of GERM CLEAN also suggests its potential in controlling of ECC.…”

The Inhibitory Effects of Ficin on Streptococcus mutans Biofilm Formation

“…The Global Burden of Disease Study 2016 revealed that caries of permanent teeth had the greatest prevalence, decayed permanent, and deciduous teeth ranked in second and fifth place, respectively, in highest incidence diseases [ 2 ]. Streptococcus mutans ( S. mutans ), a major extracellular polymeric substances producer, is the most well-known biofilm forming bacteria in oral cavity and was reported as most associated microbe in the transition of oral flora from a healthy one to a cariogenic one [ 3 ]. It has been proven that decrease or eradication of S. mutans can diminish or prevent caries development [ 4 ].…”