Antimicrobial effect of lemongrass oil against oral malodour micro-organisms and the pilot study of safety and efficacy of lemongrass mouthrinse on oral malodour

Abstract

Aims: Lemongrass oil (LG) has been reported as being effective against bacteria embedded within the biofilm. The aims of this study were to investigate antimicrobial activity against common odourigenic micro-organisms, the safety and efficacy of LG mouthrinse on oral malodour in healthy volunteers.

Methods and results: Antimicrobial activity of LG mouthrinse was examined against common odourigenic micro-organisms using broth microdilution assay and the disc diffusion method. A randomised double-blind clinical study was performed in 20 healthy volunteers. Volatile sulphur compounds (VSCs) level was measured using a Halimeter on day 0 and day 8 in each volunteer. The results showed that LG mouthrinse was effective against Aggregatibacter actinomycetemcomitans ATCC43718 and Porphyromonas gingivalis W50 but less effective against Streptococcus mutans ATCC 25175. In addition, the mouthrinse significantly reduced VSCs on day 8.

Conclusions: LG mouthrinse was able to reduce oral malodour and appeared to be safe. The overall satisfaction of the mouthrinse was acceptable. However, the spiciness and taste of the mouthrinse need to be improved.

Significance and impact of the study: This study demonstrated that the LG mouthrinse significantly reduced oral malodour. This mouthrinse would be another alternative mouthrinse choice for prevention of malodour, plaque and gingivitis.

Keywords: antimicrobial activity; lemongrass; mouthrinse; odourigenic micro-organisms; oral malodour.