Antimicrobial Efficiency of Different forms of Tea Extract (Camellia sinensis) against Cariogenic Pathogens

Abstract

Introduction: Dental caries is a frequent chronic infectious condition in the general population. Streptococcus mutans and Lactobacillus acidophilus play a significant part in the cause of dental caries. Various antimicrobials have been tried to prevent these microorganisms. Traditional herbal medicine extracted from plants has been employed as a remedy. Among them, tea leaf extract showed promising antimicrobial properties against infections. Aims: The current study was designed to assess the antibacterial activity of various types of tea extract against cariogenic microorganisms. Methods: S. mutans and L. acidophilus were grown in this in-vitro experimental study and maintained in their respective agars. Three different concentrations of 250 mg/ml aqueous, 250 mg/ml ethanolic, and 250 mg/ml aqueous with sugar solutions were prepared from Japanese green tea, Oolong Chinese tea, and Sabah black tea. Kirby-Bauer disc diffusion method was used to assess the antibacterial activity of tea extracts. As positive and negative control groups, 0.2% chlorhexidine and 1% DMSO were employed. The zone of inhibition was determined in millimetres following a 24-hour incubation period at 37 °C. Results: Japanese green tea at its three different concentrations exhibited significantly higher mean zones of inhibition of 18.33 mm, 27.70 mm, and 18.96 mm, respectively, against S. mutans at p<0.001 compared to L. acidophilus. In contrast, chlorhexidine showed 27.53 mm and 19.39 mm for S. mutans and L. acidophilus, respectively. Conclusion: Japanese green tea demonstrated superior antibacterial activity at its ethanolic concentration compared to other concentrations and the other two types of tea.