title: In vitro antibacterial activity of Camellia sinensis extract against cariogenic microorganisms.
abstract: BACKGROUND
  Dental caries, a ubiquitous multifactorial infectious disease, is primarily caused by microorganisms like Streptococcus mutans and Lactobacillus acidophilus. Use of antimicrobials is an important strategy to curb cariogenic microorganisms.
  
  
  OBJECTIVE
  The aim was to evaluate the in vitro antimicrobial activity of C. sinensis extract on S. mutans and L. acidophilus.
  
  
  METHODS
  Experimental design, in vitro study, lab setting.
  
  
  METHODS
  Aqueous, acetone and ethanolic extracts of C. sinensis were subjected to antioxidant analysis. The ethanolic extract was used for assessment of antimicrobial properties. Ethanolic green tea extract at ten different concentrations and 0.2% chlorhexidine was used. Microbiological investigations were carried out to determine the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and zone of Inhibition of the test and control agents against S. mutans and L. acidophilus.
  
  
  METHODS
  Kruskall-Wallis and Mann-Whitney U-test.
  
  
  RESULTS
  MIC of green tea extract on S. mutans and L. acidophilus was found to be 0.2% and 0.3% respectively, MBC was found to be 0.8% and 0.9%, respectively. The mean zone of inhibition for 30 μl containing 300 μg of ethanolic extract of green tea and control against S. mutans were 18.33 mm and 14.67 mm, respectively. The mean zone of inhibition for 30 μl containing 300 μg of ethanolic extract of green tea and control against L. acidophilus were 12.67 mm and 7.33 mm, respectively.
  
  
  CONCLUSIONS
  Green tea has antibacterial activity against predominant cariogenic bacteria namely S. mutans and L. acidophilus.
authors.affiliation: Department of Public Health Dentistry, Ragas Dental College and Hospital, Chennai, Tamil Nadu, India.
authors.forename: P
authors.initials: P
authors.lastname: Anita
authors.affiliation: Department of Public Health Dentistry, Ragas Dental College and Hospital, Chennai, Tamil Nadu, India.
authors.forename: Shyam
authors.initials: S
authors.lastname: Sivasamy
authors.affiliation: Department of Public Health Dentistry, Ragas Dental College and Hospital, Chennai, Tamil Nadu, India.
authors.forename: P D
authors.initials: PD
authors.lastname: Madan Kumar
authors.affiliation: Department of Public Health Dentistry, Ragas Dental College and Hospital, Chennai, Tamil Nadu, India.
authors.forename: I Nanda
authors.initials: IN
authors.lastname: Balan
authors.affiliation: Department of Biotechnology, Poonga Biotech Research Center, Plant Biotechnology Division, Choolaimedu, Chennai, Tamil Nadu, India.
authors.forename: Sumathi
authors.initials: S
authors.lastname: Ethiraj
keywords: Camellia sinensis; dental caries; green tea; phytochemical analysis