Antimicrobial activity evaluation of cardamomum extracts over oral microorganisms

Objectives: Dental plaque is formed by a group of microorganisms that adheres to the dental surface through saliva. If these microorganisms received the nutrients needed for their growth then can cause caries, periodontal disease and halitosis. It has been reported the use of natural plants in dentistry, including cardamom, as a natural adjunct in the treatment of gingivitis associated to the dental plaque. Therefore, the demonstration of its antimicrobial efficiency can make it a good alternative for the development of new mouthwashes with pleasant taste and smell, and thereby may increase its use as co-adjuvant in oral hygiene.

Assess the inhibitory action of an extract of Elettaria cardamomum against the oral microorganisms Streptococcus mutans and Candida albicans.
Methods: Previously crushed cardamom seeds were used and the extracts obtained from the methods of steam distillation and of solvent extraction using Soxhlet system with solvents having different polarities (chloroform, methanol, ethyl acetate, hexane). Microbiological tests were performed in order to verify the inhibitory action of the different oils over S. mutans and C. albicans.
Results: Steam distillation provides an extraction yield of 25% (%v/m, ml oil/g seeds) and the soxhlet method (%m/m) a maximum of 7.6% with hexane and a minimum of 0.9% with chloroform while ethyl acetate and methanol are between these yields (7.2 and 5.8 %, respectively). In regard of the antimicrobial activity, no halo of inhibition was observed over S. mutans of C. albicans with none of the extracts obtained by both extraction methods.
Conclusions: This study showed that the extracts of cardamom obtained by distillation steam and Soxlhet methods do not have inhibitory activity against two important oral microorganisms (S. mutans and C. albicans). Nevertheless, some aspects should be considered for future studies such as using other extraction techniques and different species of cardamom.