Investigation on the effect of vitamin C on growth & biofilm-forming potential of Streptococcus mutans isolated from patients with dental caries

Abstract

Background Streptococcus mutans is a major cause of dental caries. Its capacity to produce biofilm is fundamental in the pathogenesis of this ubiquitous condition. As maintaining a healthy dentition is a genuine goal given the contemporary advance in caries control, researchers are striving to achieve a breakthrough in caries therapy. We are taking the anti-cariogenic properties of vitamin C a step-further, considering the well-known evidence of the inversely proportionate relationship between salivary levels of vitamin C and dental caries. The aim of this study was to determine MIC, MBC, minimum biofilm inhibitory concentration (MBIC), and derivative measures of vitamin C against fresh clinical isolates of S. mutans to evaluate its efficacy as an anti-cariogenic agent.Results Based on the data of four independent experiments done in quadruplicates, we found a concentration-dependent inhibitory effect of vitamin C on all S. mutans strains tested. The average MBC, MIC, and MBIC of vitamin C were found to be 10.16, 9.38, and 5.61 mg/ml, respectively. Spectrophotometric quantitation of crystal violet showed diminished biofilm formation in the presence of vitamin C (p < 0.05). This inhibitory effect was not seen when vitamin C was added 18 hours post-inoculation, proving its inability to detach preformed biofilm. When compared with gentamicin, vitamin C produced a zone of inhibition that was three times as large against the clinical isolates.Conclusion Our results show that vitamin C has a negative effect on S. mutans growth and biofilm formation, which appears to be related to an inhibitory mechanism. Being the first to meticulously utilize MBIC to explore a well-known effect of vitamin C, this report aims to help in the instigation of trials of higher evidence that will ultimately culminate in repurposing vitamin C as a novel anti-cariogenic agent, albeit further studies are required to provide auxiliary evidence in this context.