Antiadherence and antibiofilm of Lavandula Angustifolia essential oil against pathogenic oral bacteria

Abstract

There are many types of oral care products in the market that can be used to solve oral diseases. However, several oral care products could contain chemicals such as chlorhexidine or sodium lauryl sulphate (SLS) that might contribute to side effects in the form of mucosal desquamation, xerostomia (dry mouth) or burning sensation in oral cavity. In order to overcome the issues related to oral disease, a substitute of antibacterial agent that is more natural is required to reduce the risk of side effects caused by the use of chemicals from common oral care products. Lavandula angustifolia is known for its antibacterial properties and its use as an essential oil. Due to its medicinal properties, current research is aimed at evaluating the antibacterial activity of essential oil from Lavandula angustifolia on the growth of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus mutans. The antibacterial activity was determined based on colour changes of minimum inhibitory concentration (MIC) reagent (3-(4, 5-dimethythiazol-2-yl)-2, 5-diphenyltetrazolium bromide) during the initiation of MIC experiment using microbroth dilution method. About 0.1% chlorhexidine (w/v) solution was used as a positive control while 10% of dimethyl sulfoxide (DMSO) (v/v) was used as a negative control. The MIC value of essential oil was determined at 0.78% for both E. coli and S. aureus, whereas the MIC values of the same were at 1.56% and 6.25% for S. mutans and P. aeruginosa, respectively. In regard to the value of MIC, each bacteria were subjected to further test on the antiadherence and antibiofilm activity. Accordingly, the anti-adherence activity for E. coli and P. aeruginosa were of 65.95 ± 6.83% and 74.07 ± 1.85%, which was slightly high compared to S. aureus and S. mutans that produced anti-adherence activities at 61.78 ± 1.27% and 48.52 ± 13.17%, respectively. E. coli and P. aeruginosa also exhibited a slight high in antibiofilm activity in a range of 85% to 90% after using essential oil from lavender as compared to 77% to 79% of anti-biofilm activity in S. aureus and S. mutans. The morphological analysis by FESEM showed that S. mutans encountered modifications to its cellular membrane. A much severe defect also had been observed on the coccus-shaped bacteria whenever S. mutans were exposed to essential oil from lavender at MIC and half the MIC values. As a conclusion, the essential oil from Lavandula angustifolia is capable to reduce the growth of oral bacteria which can be implemented as a potential substitute ingredient to common chemicals from oral care products.