Assessment of Antimicrobial Effectiveness of Neem and Clove Extract Against Streptococcus mutans and Candida albicans: An In vitro Study

Niger Med J. 2019 Nov-Dec;60(6):285-289. doi: 10.4103/nmj.NMJ_20_19. Epub 2020 Feb 24.

Abstract

Background: There is increasing interest to develop antimicrobial aids from alternative sources such as medicinal plants for the treatment of infectious diseases. Neem and clove are known to have antimicrobial properties.

Aim: The study aimed at detecting the antibacterial and antifungal activity of neem and clove extract against Streptococcus mutans and Candida albicans.

Materials and methods: Strains of S. mutans and C. albicans and selective media for growing micro-organisms were procured. Antimicrobial activity was assessed using two methods, by determining the minimum inhibitory concentration (MIC) using the broth dilution method and determining the zone of inhibition using well diffusion method on mitis salivarius bacitracin selective for S. mutans and Saboraud's dextrose agar plates for C. albicans. One way ANOVA with post hoc analysis was done to compare the antimicrobial activity of extracts and 0.2% chlorhexidine.

Results: MIC of neem extract was found to be 4.2 mg/ml and 5.0 mg/ml against S. mutans and C. albicans, respectively. While for cloves, it was 5.5 mg/ml for both. Neem had the highest antibacterial activity with a mean zone of inhibition of 11.4 mm followed by chlorhexidine and cloves whereas antifungal activity was highest for chlorhexidine (14.4 mm) followed by neem and clove.

Conclusion: The result of the study established that both plant extracts possess antimicrobial activity against common microbes present in the oral cavity.

Keywords: Clove; minimum inhibitory concentration; neem; zone of inhibition.