New trends in dentistry: plant extracts against Enterococcus faecalis. The efficacy compared to chlorhexidine

Abstract

Enterococcus faecalis is an important pathogen associated with endodontic diseases, and its elimination and control are of paramount importance, as it represents one of the major causes of failure in the treatment of endodontic disease. Twenty-five plant extracts obtained from Brazilian forests were found to be effective against planktonic E. faecalis and were subjected to two traditional antibacterial assays, the microdilution broth assay (MDBA) and the disk diffusion assay (DDA), using chlorhexidine (CHX) as a control. Seven out of 25 extracts showed significant antibacterial activity and were tested in a biofilm assay, and three of these extracts were subjected to chemical fractionation. Residues were tested for their antibacterial activity, and the first chemical findings were described based on thin layer chromatography (TLC). Extracts obtained from Ipomoea alba, Symphonia globulifera and Moronobea coccinea showed significant bactericidal activity in the MDBA. The same I. alba and S. globulifera extracts, as well as the extract obtained from Connarus ruber var. ruber, showed significant activity in the DDA. RH2O obtained from Psidium densicomum and Stryphnodendron pulcherrimum showed better antibacterial activity compared to the respective crude extracts and CHX. TLC analysis showed that phenolic compounds and triterpenes represent the first findings of chemical groups that may occur in all species. The results of the present study include the discovery of six active extracts against planktonic E. faecalis and support further testing via assays involving biofilm formation, as well as the determination of the compounds' chemical profiles, as their activity was significantly better than that observed for CHX.

The influence of Brazilian plant extracts on Streptococcus mutans biofilm

“…As S. mutans was previously used in the identification of antibacterial extracts in microdilution assays 1,19 , the biofilm used in the current study was exclusively composed of the same bacteria. If one or more extracts showed activity against the single-species biofilm, then it was selected to be evaluated against a biofilm composed of more than one bacterial species.…”

“…Although much has been done in the search for new leads from plants, it is estimated that only 6% of the species have been studied so far 5 . In Brazil, strong efforts are made in order to search for new antibacterials from local plants, using not only information regarding popular uses 23 , but also the establishment of throughput assays aiming at the rapid analysis of a large number of plant extracts against a variety of microorganisms 1,18,22,26 .…”

Epidihydropinidine, the main piperidine alkaloid compound of Norway spruce (Picea abies) shows promising antibacterial and anti-Candida activity

“…Bacillus cereus, Salmonella enterica, Staphylococcus aureus and Pseudomonas aeruginosa were selected according to their ability to induce food poisoning or spoilage of food [7,67]. In addition, Enterococcus faecalis was chosen as a grampositive model bacterium commonly causing nosocomial infections [68]. The fungal species, Candida albicans and C. glabrata, were selected according to their clinical relevance of being the most frequent causative agents of systemic fungal infections as well as of opportunistic infections in mouth [43,69].…”

Phytochemical screening, total phenolic content and antioxidant activity of some plants from Brazilian flora

“…(Fabaceae) is an arboreal species occurring in the Amazonian forest and Atlantic forest in northeast Brazil (Scalon, 2007). Castilho et al (2013) reported the antibacterial activity of extracts of this plant against oral pathogens.…”