Antimicrobial Efficacy of Chemical and Herbal Agents against Streptococcus mutans: An in vitro study

Ravinder Kaur Gulati, Parul Bhatnagar, Akash Bhatnagar


Objective: To compare and evaluate antimicrobial efficacy of chlorhexidine gluconate and fennel seeds against Streptococcus mutans. Material and Methods: Three agar petri dishes for Streptococcus mutans were prepared. The methanolic extract of fennel seed and 0.2% chlorhexidine were inoculated on the each petri dish and incubated at 37ºC for 24 hours. Zone of growth inhibition for each extract was measured in millimeters using antibiotic inhibiting zone measuring scale. Data was analyzed using SPSS statistical software. The comparison of inhibition zone against S. mutans using CHX and fennel seed extract was done using Mann-Whitney and Wilcoxon tests. All statistical analyses were set at a significance level of p<0.05. Results: The mean of zone of inhibition of S. mutans after inoculation with 0.2% chlorhexidine and fennel seed extract are 21.44 ±1.46, 15.34 ±0.74 respectively. There was statistically significant difference in the mean of inhibition zone between 0.2% chlorhexidine and fennel seed against S. mutans (p=0.047). Conclusion: Chlorhexidine and fennel seed are effective in inhibiting the growth of cariogenic bacteria. Therefore, both herbal and chemical agents can be effectively used to reduce pathogenic oral microflora.


Chlorhexidine; Seeds; Streptococcus mutans.

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Brambilla E, Twetman S, Felloni A, Cagetti MG, Canegallo L, Garcia-Godoy F, Strohmenger L. Salivary mutans streptococci and lactobacilli in 9- and 13-year-old Italian schoolchildren and the relation to oral health. Clin Oral Investig 1999; 3(1):7-10.

Ophori EA, Eriagbonye BN, Ugbodaga P. Antimicrobial activity of propolis against Streptococcus mutans. Afr J Biotechnology 2010; 9(31):4966-9.

Sundas S, Rao A. Comparative evaluation of chlorohexidine and sodium fluoride mouth washes on streptococcus mutans. J Nepal Dent Association 2011; 12(1):17-21.

Farah CS, McIntosh L, McCullough MJ. Mouthwashes. Australian Prescriber 2009; 32(6):162-4. doi: 10.18773/austprescr.2009.080.

Ercan E, Zekinci T, Atakul F, Gul K. Antibacterial activity of 2% chlorhexidine gluconate and 5.25% sodium hypochlorite in infected root canal: In vivo study. J Endod 2004; 33(2):174-9. doi: 10.1097/00004770-200402000-00005.

Malhotra R, Grover V, Kapoor A, Saxena D. Comparison of the effectiveness of a commercially available herbal mouthrinse with chlorhexidine gluconate at the clinical and patient level. J Indian Soc Periodontol 2011; 15(4):349-52. doi: 10.4103/0972-124X.92567.

Crellin JK, Philpott J, Tommie AT. A reference guide to medicinal plants: Herbal medicine past and present. Duke University Press 1989; 1:207-8.

Das S, Anjeza C, Mandal S. Synergistic or additive antimicrobial activities of Indian spice and herbal extracts against pathogenic, probiotic and food-spoiler microorganisms. Int Food Res J 2012; 19(3):1185-91.

Ozcan MM, Chalchat JC, Arslan D, Ates A, Unver A. Comparative essential oil composition and antifungal effect of bitter fennel fruit oils obtained during different vegetarians. J Med Food 2006; 9(4):552-4. doi: 10.1089/jmf.2006.9.552.

Mimica N, Kujundzic S, Sokovic M, Couladis M. Essential oil composition and antifungal activity of foeniculum vulgare Mill obtained by different distillation conditions. Phytother Res 2013; 17(4):368-72. doi: 10.1002/ptr.1159.

Vasconcelos LC, Sampaio FC, Sampaio MC, Pereira Mdo S, Higino JS, Peixoto MH. Minimum inhibitory concentration of adherence of Punica granatum Linn (pomegranate) gel against S. mutans, S. mitis and C. albicans. Braz Dent J 2006; 17(3):223-6. doi: 10.1590/S0103-64402006000300009.

Nóbrega DRM, Santos RL, Soares RSC, Alves PM, Medeiros ACD, Pereira JV. A randomized, controlled clinical trial on the clinical and microbiological efficacy of Punica granatum Linn mouthwash. Braz Res Pediatr Dent Integr Clin 2015; 15(1):301-8. doi: 10.4034/PBOCI.2015.151.32.

Subramaniam, P, Eswara, U. Effect of different types of tea on Streptococcus mutans: An in vitro study. Indian J Dent Res 2012; 23(1):43-9.

Flotra L. Different modes of chlorhexidine application and related local side effects. J Periodontal Res 1973; 12:41‑4.

Gulfraz M, Mehmood S, Minhas N, Jabeen N, Kausar R, Jabeen K, Arshad G. Composition and antimicrobial properties of essentialoil of Foeniculum vulgare. African J Biotechnology 2008;7(24):4364-8.

Chaouche T, Haddouchi F, Lazouni HA, Bekkara FA. Phytochemical study of the plant Foeniculum vulgare Mill. DerPharmacia Lettre 2011; 3(2):329-33.

Venkataranghavan K, Shah S, Choudhary P, Kaur M, Shah S, Trivedi K. Effectiveness of new generation anticavity mouthwash on streptococcus mutans and lactobacillus acidophilus count: A microbial study. World J Dent 2014; 5(3):152-6.

Nagappan N, John J. Antimicrobial efficacy of herbal and chlorhexidine mouth rinse - A systematic review. IOSR J Dent Med Sci 2012; 2(4):5-10.

Prajapati RA, Raol BV. The study on the efficacy of some herbal extracts for the control of dental caries pathogen streptococcus mutans. Int J Pharm Sci Health Care 2014; 1(4):49-58.

Ajithkrishnan CG, Thanveer K, Singh RP. An in-vivo evaluation of theeffect of fennel seeds chewing on salivary pH. J Oral Health Community Dent 2014; 8(2):79-81.