Comparative evaluation of antimicrobial potential of herbal extracts on Streptococcus mutans and Enterococcus faecalis: An in vitro study


  • Pranati Tatekalva Under Graduate Student Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India
  • Haripriya Subbaiyan Senior LecturerDepartment of Conservative Dentistry and EndodonticsSaveetha Dental College, Saveetha Institute of Medical and Technical Sciences,Saveetha University, Chennai, India.
  • Shanmugam Rajesh Kumar Professor Department of Pharmacology Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India



Though aloe vera extract, green tea extract and coriander oil are proven antimicrobial agents, very little information is available regarding its effects on oral bacteria, Streptococcus mutans,which is responsible for initiating caries and Enterococcus faecalis, responsible for failure of root canal treatment. Objective: To find the antimicrobial activity of aloe vera extract, black tea extract and coriander oil against S. mutans and E. faecalis. Materials and Methods: The agar well diffusion method was used to determine the antibacterial activity of Aloe vera extract, black tea extract and coriander oil. Different concentration of prepared plant extracts and coriander seed oil (50 & 100 µl) was incorporated into the wells and the plates containing S. mutans and E. faecalis were incubated at 37 ºC for 24h. The antibiotic (amoxicillin 30 µl) was used as positive control. Zone Of Inhibition (ZOI) was recorded in each plate. Results: For S. mutans, the maximum ZOI was created by coriander oil with a diameter of 25.00±0.58 mm at 50 µl and for E. faecalis, maximum ZOI was created by aloe vera extract 16.00±0.58 mm at 100 µl concentration which were far better than the control: amoxicillin 30 µl concentration.

Conclusion: The extracts of Aloe vera, black tea and coriander oil, showed significant activity against the investigated microbial strains, Streptococcus mutans and Enterococcus faecalis which further helps in the development of new topical agents that help in reducing the numbers of these organisms present in the oral cavity.



Oral microbiota; Aloe vera; black tea; coriander oil; E. faecalis; S.mutans.


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