Acmella paniculata, also known as ’Subang nenek’ in Malaysia, has been used to treat diseases such as toothache and gum infections. People called it a toothache plant, and it has been widely used as traditional medicine. Therefore, this study aims to investigate the antibacterial activities of A. paniculata leaves and flowers extracts towards Streptococcus mutans by using disc diffusion assay, minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) methods. Besides, the anti-biofilm activity of all the extracts also been determined by using a crystal violet assay. As the results, n-hexane and methanol extracts from leaves showed the highest inhibition zone towards S. mutans when compared to DCM and acetone extracts. Meanwhile, for the flowers extract, n-hexane and DCM showed the highest inhibition zone towards S. mutans compared to methanol and acetone extracts. The best results were then tested for MIC and MBC tests. As for the MIC values of n-hexane and methanol leaves extracts were 25 mg/mL, respectively, and the MBC values were 50 and 100 mg/mL, respectively. Whereas MIC values for n-hexane and DCM flowers extracts were 12.5 mg/mL, respectively, and the MBC values were 50 mg/mL, respectively. Biofilm formation of S. mutans showed decrement up to 70% after exposure to both leaves extract (n-hexane and methanol) and n-hexane flower extract. Still, it differed when exposing to DCM flower extract, and the result showed that the biofilm activities of S. mutans were inhibited at 80% after treated with DCM flowers extracts. In conclusion, n-hexane leaves extract, methanol leaves extract, n-hexane flowers extract, and DCM flowers extract of A. paniculata demonstrated bactericidal properties against S. mutans. © International Journal of Research in Pharmaceutical Sciences.

The study aimed to determine the in-vitro inhibitory effect of Cinnamomum zeylanicum Blume (cinnamon) and Eugenia caryophyllata (clove) oils on combined Porphyromonas gingivalis and Fusobacterium nucleatum biofilm. Following a steam distillation extraction technique, oils from cinnamon bark and clove buds were tested for their antibacterial anti-adhesion and anti-biofilm activities on mixed biofilm containing P.gingivalis and F.nucleatum. The quantification of viable and adhered bacterial cells on 96-well plates using the crystal violet test was analysed and morphology of the bacteria in biofilm was observed under the scanning electron microscope (SEM). Our study demonstrated C.zeylanicum oil inhibited satisfactory anti-adhesion effect and significantly disrupted the biofilm formation at 1.25-5.0 mg/mL whereas E.caryophyllata oil suppressed the adhesion of bacteria and disrupted the formation of biofilm at 0.63-5.0 mg/mL. The SEM study showed prominent changes including ruptures and flatten bacterial wall in samples with E.caryophyllata oil while pitted and flatten cells were seen in C.zeylanicum samples compared to the smooth and distinguished cell wall seen in untreated samples or even more damaged cells in Ampicillin samples. We conclude that C.zeylanicum and E.caryophyllata oils showed significant in vitro anti-biofilm properties against mixed P.gingivalis and F.nucleatum biofilm and prominently altered the bacterial wall morphology. This finding may suggest potential therapeutic properties of these oils in controlling biofilm-related oral diseases. 2019 Journal of International Dental and Medical Research.