Effectiveness of Bioactive Compound as Antibacterial and Anti-Quorum Sensing Agent from Myrmecodia pendans: An In Silico Study.

BACKGROUND: antibiotic resistance encourages the development of new therapies, or the discovery of novel antibacterial agents. Previous research revealed that Myrmecodia pendans (Sarang Semut) contain potential antibacterial agents. However, specific proteins inhibited by them have not yet been identified as either proteins targeted by antibiotics or proteins that have a role in the quorum-sensing system. This study aims to investigate and predict the action mode of antibacterial compounds with specific proteins by following the molecular docking approach. METHODS: butein (1), biflavonoid (2), 3″-methoxyepicatechin-3-O-epicatechin (3), 2-dodecyl-4-hydroxylbenzaldehyde (4), 2-dodecyl-4-hydroxylbenzaldehyde (5), pomolic acid (6), betulin (7), and sitosterol-(6'-O-tridecanoil)-3-O-ß-D-glucopyranoside (8) from M. pendans act as the ligand. Antibiotics or substrates in each protein were used as a positive control. To screen the bioactivity of compounds, ligands were analyzed by Prediction of Activity Spectra for Substances (PASS) program. They were docked with 12 proteins by AutoDock Vina in the PyRx 0.8 software application. Those proteins are penicillin-binding protein (PBP), MurB, Sortase A (SrtA), deoxyribonucleic acid (DNA) gyrase, ribonucleic acid (RNA) polymerase, ribosomal protein, Cytolysin M (ClyM), FsrB, gelatinase binding-activating pheromone (GBAP), and PgrX retrieved from UniProt. The docking results were analyzed by the ProteinsPlus and Discovery Studio software applications. RESULTS: most compounds have Pa value over 0.5 against proteins in the cell wall. In nearly all proteins, biflavonoid (2) has the strongest binding affinity. However, compound 2 binds only three residues, so that 2 is the non-competitive inhibitor. CONCLUSION: compound 2 can be a lead compound for an antibacterial agent in each pathway.

A terpenoid isolated from sarang semut (Myrmecodia pendans) bulb and its potential for the inhibition and eradication of Streptococcus mutans biofilm.

BACKGROUND: Dental caries remains a serious problem due to its detrimental effects on individual health and quality of life. The bulbs of Myrmecodia pendans (Merr & Perry), native plants of Papua, have been used as natural remedies for tumours, gout, diarrhoea, and fever. In this study, one of the active compounds of M. pendans was isolated, and its biological activity against the formation of Streptococcus mutans ATCC 25175 biofilm was tested. METHODS: M. pendans was extracted with ethyl acetate using a Soxhlet apparatus. The extract was then separated, and chromatographic purification provided the isolated compound. The structure of the active compound was then characterized using UV, IR, NMR, and MS spectrometry. The obtained compound was added to S. mutans biofilms to determine the MBIC and MBEC values. RESULTS: The compound isolated from M. pendans was determined to be a labdane diterpene derivative with the formula C31H50O3. The MBIC value of the terpenoid towards the S. mutans biofilms was 50 ppm, and the MBEC value for the 1 min induction time was 40%. CONCLUSION: The terpenoid extracted from M. pendans has the potential to be developed into an antibacterial agent particularly for preventing the formation of biofilms.

MIC, MBIC, MBEC analyses of garlic extract (Allium sativum) from Indonesian variety against Streptococcus mutans

Garlic (Allium sativum) has been used for traditional medicine since ages. It has many uses such as an antioxidant, antiseptic, anti-viral, anti-fungal, anti-cancer, anti-aging, reduce the risk of heart disease, and antibacterial1. Aim: This study was designed to evaluate the inhibition and eradication ability for garlic against Streptococcus mutans, the bacteria that cause dental caries. Methods: Garlic extract was obtained from Ciwidey garlic maseration process in etanol 96%. MIC was a test to measure the inhibition ability of garlic extract against Streptococcus mutans in planktonic form, and MBIC in biofilms form. MBEC was a test to measure the eradication ability of garlic extract against Streptococcus mutans in biofilms form. Statistic analysis using ANOVA followed by post hoc with ρ value <0.05. Results: The garlic extract showed MIC value at 9.39 % and MBIC value at 37.5 % but was not observed to have eradication activity against Streptococcus mutans in biofilms form up to concentration 37.5%. Conclusion: Garlic extract inhibit Streptococcus mutans both in planktonic and biofilm form. Garlic extract has no eradication activity against Streptococcus mutans in biofilms form up to concentration 37.5% (AU)