Background: Streptococcus mutans and Streptococcus sanguinis are Gram-positive bacteria that cause dental caries. The MurA enzyme is a catalyst in the formation of peptidoglycan in the bacterial cell wall making it ideal as an antibacterial target. Basil (Ocimum americanum) is an edible plant medicine that diverse, very widely spreading, used as herbal for a long time, and it was reported to have pharmacology effect as antibacterial activity. The purpose of this study is to identify antibacterial compounds from O. americanum and analyze their inhibition activity to the MurA enzyme. Methods: Fresh leaves from O. americanum extracted with n-hexane and purified by a combination of column chromatography on normal and reverse phase together with guided by in vitro bioactivity assay against S. mutans ATCC 25175 and S. sanguinis ATCC 10556, respectively, while in silico molecular docking simulation of lauric acid (1) using PyRx 0.8. Results: The structure determination of antibacterial compound by spectroscopic methods resulted in an active compound 1 as lauric acid. The in vitro evaluation of antibacterial activity compound 1 showed the MIC and MBC of 78.13 & 156.3 ppm and 1250 & 2500 ppm against S. sanguinis and in S. mutans, respectively. Further analysis in silico evaluation as MurA Enzyme inhibitor, lauric acid (1) has a binding affinity of -5.2 Kcal/mol those higher than fosfomycin. Conclusion: The lauric acid has potency as a new natural antibacterial agent through the MurA inhibition in bacterial cell wall biosynthesis.

Background Streptococcus sanguinis is Gram-positive bacteria that contribute to caries. Many antibacterial agents are resistant against bacteria so that the discovery of new antibacterial agents is a crucial issue. Mechanism of antibacterial agents by disrupting cell wall bacteria is a promising target to be developed. One of the enzymes contributing to the cell wall is MurA enzyme. MurA is an enzyme catalyzing the first step of peptidoglycan biosynthesis in the cell wall formation. Inhibiting MurA is an effective and efficient way to kill the bacteria. Source of bioactive compounds including the antibacterial agent can be found in natural product such as herbal plant. Piper betle L. was reported to contain active antibacterial compounds. However, there is no more information on the antibacterial activity and molecular mechanism of P. betle ’s compound against S. sanguinis . Purpose The study aims to identify antibacterial constituents of P. betle L. and evaluate their activities through two different methods including in vitro and in silico analysis. Materials and Methods The antibacterial agent was purified by bioactivity-guided isolation with combination chromatography methods and the chemical structure was determined by spectroscopic methods. The in vitro antibacterial activity was evaluated by disc diffusion and dilution methods while the in silico study of a compound binds on the MurA was determined using PyRx program. Results The antibacterial compound identified as allylpyrocatechol showed inhibitory activity against S. sanguinis with an inhibition zone of 11.85 mm at 1%, together with MIC and MBC values of 39.1 and 78.1 μg/mL, respectively. Prediction for molecular inhibition mechanism of allylpyrocatechols against the MurA presented two allylpyrocatechol derivatives showing binding activity of −5.4, stronger than fosfomycin as a reference with the binding activity of −4.6. Conclusion Two allylpyrocatechol derivatives were predicted to have a good potency as a novel natural antibacterial agent against S. sanguinis through blocking MurA activity that causes disruption of bacterial cell wall.

Background Dental caries is a widespread disease that causes dental tissue destruction and leads to local and general complications. Gram-positive bacteria including Streptococcus mutans , Streptococcus sanguinis , and Enterococcus faecalis take part in dental caries formation. Gram-positive bacteria have cell walls that consistof a thick layer of peptidoglycan which maintains the strength and rigidity of the bacteria, as well as bacteria guard from internal osmotic pressure. The biosynthesis of peptidoglycan involves many enzymes, including the Mur family, penicillin binding protein (PBP), and sortases. Purpose This research has the intention to screen and examine the antibacterial compound of edible plant Kemangi ( Ocimum basilicum L.) in terms of how it fights against some oral pathogenic bacteria of E. faecalis ATCC 29212, S. mutans ATCC 25175, and S. sanguinis ATCC 10566. Materials and Methods The O. basilicum L. was macerated by several organic solvents to obtain the extracts, before then being purified using several combinations of chromatography methods and the compound was discovered via spectroscopic methods. For the assay against bacteria, the extracts and compounds were tested using agar well diffusion and microdilution assay. Results The isolated compound was identified as β-sitosterol. The compound activity against bacteria was evaluated by in vitro assay against S. sanguinis ATCC 10566 and E. faecalis ATCC 29212 with the MIC and MBC value of 25,000 and 50,000 ppm, respectively. The compound was also tested by in silico study using the molecular docking method. The molecular interaction between β-sitosterol and the protein target showed a lower binding affinity value than the native ligand and other positive controls for each protein. Based on the amino acid residue bound to the ligands, β-sitosterol on MurA and SrtA is not competitive to the positive control, showing potential as a natural antibacterial agent. Meanwhile, on the MurB and PBP, β-sitosterol and positive control do compete with each other. Conclusion The compound, isolated from O. basilicum L. leaf, was determined as β-sitosterol, which has the molecular formula C 29 H 50 O. The antibacterial activity of β-sitosterol by in vitro assay showed weak antibacterial activity, yet exhibited the potential to inhibit the biosynthesis of peptidoglycan and prevent bacteria cell wall formation by inhibiting MurA and SrtA activity via docking simulation.

Background: Dental caries is an oral disease generated by pathogenic bacteria, Enterococcus faecalis, which is most frequently found in teeth with pulp necrosis. On the other hand, the use of the medicinal plant to treat pathogenic disease, including caries is an alternative option, which consumes synthetic drug having a side effect. Objective: The purpose of this study is to isolate antibacterial agents from Buah Merah (Pandanus conoideus Lam) and to test the antibacterial activity of those compounds against Enterococcus faecalis ATCC 29212. Methods: Isolation of the antibacterial constituents from Buah Merah used a combinational column chromatography technique which include a normal and reversed-phase. The chosen fraction of each separation is based on the most active fraction. The compounds at various concentrations, 1000 - 20000 μg/mL, were assessed against E. faecalis ATCC 29212 by agar disc diffusion method, and chlorhexidine 2000 μg/mL was used as a positive control. Results: Four compounds isolated from Buah Merah were determined as flavonoid 1, diterpenoid 2, and two fatty acid derivatives 3 and 4. The compounds were then tested against E. faecalis cultured to find inhibition zones, and the study found that only compound 1 identified as Quercetin-3-O-glucose showed an inhibited zone 88 mm at 20000 ppm. Conclusion: This study demonstrated that ethyl acetate fraction of Buah Merah contains an antibacterial flavonoid active against E. faecalis. This research gives information for the use of this plant in herbal medicine and contributes to the necessity of a new antibacterial agent for oral infectious disease. Moreover, this data can be based on information to find the substituted antiseptic applied in the dentistry field.

Background:Caries and periodontitis are dental diseases caused by bacteria of S. sanguinis, S. mutans, and E. faecalis with three main etiological factors of the host, substrate, and time. Objective:This study proposed to investigate the antibacterial effects of Buah Merah (Pandanus conoideus Lam.) against oral bacteria of E.faecalis, S. mutans, and S. sanguinis. Materials and Methods:The Buah Merah was extracted with different solvents to yield n-hexane, ethyl acetate, methanol, and H 2 O extracts. The concentrations of single and mixture extracts were adjusted for antibacterial assay against bacteria of E. faecalis, S. mutans, and S. sanguinis strains through agar well diffusion assay with chlorhexidine, fosfomycin, and quercetin used as positive controls. Results:The ethyl acetate extract showed highest antibacterial activity against three oral bacterial of E. faecalis, S. mutans, and S. sanguinis with inhibition zones values of 9.3, 12.3, and 17.9 mm at 40%, respectively, together with their MIC and MBC values of 1250 & 2500, 0.312 & 0.625, and 0.312 & 0.625 ppm, respectively. For the formulation of extracts, combinations samples test gave various effects to different bacteria, with the best activity showed by methanol-ethyl acetate (M-Ea) extracts against S. mutans with an inhibition zone of 16.25 mm at 40 ppm. The strong and synergistic effect of methanol extract against S. mutans was supported by inhibition zones of the formulation of methanol extract-fosfomycin which showed an inhibition zone of 25.9 mm at 10 ppm. Conclusion:The extracts of Buah Merah demonstrated antibacterial activity against oral bacteria of E. faecalis, S. mutans, and S. sanguinis and gave important information for further in vivo clinical studies to determine the exact dosages and its effectiveness in practical application. These results prove the antimicrobial effects of Buah Merah extracts as alternative natural drugs with synergistic effects of active constituents. of caries: host, substrate, and time. Streptococcus mutans is included as cariogenic bacteria because it is able to produce acid and carbohydrate quickly. The pathogenesis process of teeth caries is marked by the ability to grow in an acid surrounding and quick sugar metabolism characteristic for organic acid including lactic acid [1, 2].