# Antibacterialativity of _Lysimachia nummularia_ L. in Oro-Dental Diseases
## 4 Discussion
The explanation of the effects obtained by the extracts studied on reference bacterial strains and isolated from pathological products is related to antibacterial mechanisms produced by the targeted secondary metabolites, which are cited in the specialized literature, as follows [30]. Caffeic acid, present in the highest concentration in the aerial part of the plant, has an important antibacterial effect through metabolic disturbances related to dysfunctions of the bacterial respiratory processes, followed by the acidification of the intracytoplasmic pH and death [25; 31]. When consumed, it is metabolized in the body into several metabolites, including caffeic, ferulic, and quinic acids [32]. Caffeic acid has been studied for its potential antibacterial effects. Some studies suggest that caffeic acid may have antibacterial activity against a range of bacteria, including both Gram-positive and Gram-negative species. For example, one study found that caffeic acid was effective against _Staphylococcus aureus_, a common cause of bacterial infections [33]. Caffeic acid has been studied for its potential effects on oral health and has shown promising results in preventing and treating oral diseases [32]. Several studies have found that caffeic acid can inhibit the growth of oral pathogens, such as _Streptococcus mutans_ and _Porphylomonas gingivalis_, which are associated with dental caries and periodontitis, respectively. Caffeic acid works by disrupting the bacterial cell membrane and inhibiting the activity of enzymes involved in bacterial metabolism [34]. Chlorogenic acid, identified in the highest concentration in the 40% alcoholic extract of the plant's roots, has important antibacterial properties achieved by seriously disrupting bacterial metabolism by affecting the bacterial wall and the permeability of the cytoplasmic membrane, as well as by neutralizing the pathogenicity factors of some bacteria [35]. Chlorogenic acid has also been found to have antibacterial effects against several oral pathogens, including _Streptococcus mutans_, which is a major contributor to dental caries. It works by disrupting the bacterial cell membrane and inhibiting bacterial metabolism [36]. The phenolic acids have antioxidant properties and anti-inflammatory effects, making them potentially useful compounds for the prevention and treatment of various diseases. Overall, the potential benefits of these acids for oral health are promising, and further research is needed to fully understand the extent of these benefits. However, incorporating these extracts in dental products may be a beneficial strategy for promoting oral health [37]. _Trans-resveratrol, a well-known phenolic compound, has antibacterial effects against _E. faecalis_ by disrupting the bacterial cell membrane and inhibiting bacterial metabolism, resulting in cell death. Other phenolic compounds, such as caffeic acid and chlorogenic acid, also exhibit antibacterial effects against _E. faecalis_. The presence of _trans-resveratrol, a phytoalexin found in plants sensitive to oxidative processes, can contribute to inhibitory activity. _Trans-resveratrol stimulates the production of phytoalexin in various plants, including grapes, suggesting that this is one of its mechanisms for strengthening plant defenses. Additionally, _trans-resveratrol displays antibacterial effects against _E. faecalis_ in both planktonic cells and biofilms [13; 38; 39; 40; 41]. The results obtained in Tables 3 and 4 indicate that the extracts obtained from _Lysimachia nummularia_ L. show antibacterial activity against bacterial species isolated from oro-dental diseases and reference strains. Dried extracts obtained from _Lysimachia nummularia_ L. (_terba, flores_, and _radix_) showed zones of inhibition against the Gram-positive bacterium _S. mitis_, with average diameters of 6 \(\pm\) 0.02 mm for all three extracts. However, the extracts did not show a significant inhibition against the Gram-positive bacterium _S.