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

Antibacterial Activity of Gallic Acid from the Leaves of Altingia excelsa Noronha to Enterococcus faecalis

AIM : The aim of this study was to determine the antibacterial compound of Altingia excelsa leaves to inhibit the growth of Entrococcus faecalis. METHODS : The study was true experimental laboratory design. Separating the ethyl acetate extract via their compounds using various chromatographic techniques. Four extracts from A. excelsa leaves was obtained by the maceration method. The highest inhibitory effect was then continued to be isolated until one compound was obtained. Therefore, additional assay to determine chemical structure of compounds was done using UV spectra, infrared (IR), core magnetic resonance (NMR), and comparison with spectra data from the literature. The data were analyzed by ANACOVA assay. RESULTS : The highest inhibitory effect was the ethyl acetate extract. The chemical structure of compound 1 was identified as an acidic compound 3,4,5 -trihydroxy benzoate, namely as the gallic acid which had inhibitory effect against Enterococcus faecalis. Antibacterial test against Enterococcus faecalis was done to determine inhibitory effect by its compound and MIC values showed of 12.25 µg/mL. CONCLUSION : Gallic acid as the compound of Altingia excelsa leaves had a strong inhibitory effect to Enterococcus faecalis.

Remedial Aspect of Zinc Oxide Nanoparticles Against Serratia Marcescens and Enterococcus Faecalis

Zinc oxide nanoparticles (ZnO NPs) have been widely used in biomedical applications due to their high biocompatibility and low toxicity to humans. The present work aimed to investigate the antibacterial effects of different concentrations of ZnO NPs on two opportunistic pathogens, Serratia marcescens and Enterococcus faecalis. The surface interaction between nanoparticles and bacterial cell wall, and the subsequent morphological alterations on the bacterial surface, were examined through Fourier transform infrared spectroscopy and scanning electron microscope. The energy dispersive X-ray analysis was used to confirm the elemental composition of ZnO NPs and the cellular accumulation of ZnO NPs in bacteria. The growth-inhibitory test demonstrated a dose-dependent growth inhibitory effect of ZnO NPs against both the test bacteria, as the higher concentration of nanoparticles caused the higher bacterial growth inhibition. The results showed that ZnO NPs caused a higher growth inhibition (63.50 ± 2.50%) on the Gram-positive bacterium E. faecalis compared to the Gram-negative bacterium S. marcescens (51.27 ± 4.56%). Fourier transform infrared spectrum revealed the possible involvement of hydroxyl, carboxyl, amides, methylene, and phosphate groups from the biomolecules of bacterial cell wall such as proteins, carbohydrates, lipids, and phospholipids in the interaction of ZnO NPs on bacterial cell surface. Energy dispersive X-ray analysis showed the higher accumulation of ZnO NPs in E. faecalis than S. marcescens analogous to the bacterial growth inhibition. Scanning electron microscopy images confirmed the antibacterial properties of ZnO NPs, showing the loss of integrity of cell membrane and distortion of bacterial cells. Hence, the potential of ZnO NP as an antibacterial agent against S. marcescens and E. faecalis has been confirmed.

The ethnobotanical relevance of the tribe Symphonieae (Clusiaceae) around the world

ETHNOPHARMACOLOGICAL RELEVANCE

The tribe Symphonieae (Clusiaceae) encompasses 48 species accommodated in seven genera (Lorostemon, Montrouziera, Moronobea, Pentadesma, Platonia, Symphonia and Thysanostemon). Parts of these plants, mainly the exudates and the seeds oil are useful for different purposes, especially for treating dermatological conditions. In addition to the role in the folk medicine, some species are of great economic and cultural importance for native people from different continents.

AIM OF THE REVIEW

The goal of this review is to critically summarize the current knowledge on systematics, ethnobotanical, chemical and pharmacological aspects of species from the tribe Symphonieae, as well as to provide support for future taxonomic and phylogenetic studies on the Clusiaceae family.

MATERIALS AND METHODS

The available information was gathered from many different databases (Web of Science, ScienceDirect, Scopus, Pubmed, ChemSpider, SciFinder, ACS Publications, Wiley Online Library, Useful Tropical Plants Database, Google Scholar). Additional data from books, theses and dissertations were also included in this review.

RESULTS

Chemical studies of Symphonieae have demonstrated that the genera are a source of benzophenones, xanthones and biflavonoids. Components as sesquiterpenoids, triterpenoids, flavonoids, free fatty acids, among others, have also been reported. Extracts and compounds isolated from a variety of species have been exhibiting antimicrobial, cytotoxic and antiprotozoal activities, corroborating part of their medicinal uses. In addition, certain species produce edible fruits and a kind of "butter" with economic importance. All species produce exudate, which often has great relevance in the daily lives of local people.

CONCLUSION

Several species of Symphonieae have potential therapeutic applications and some of them have been investigated to scientifically validate their popular uses. In addition, a number of species have proved to be a rich source of promising pharmacologically active compounds. Finally, the value of fruits, exudate and butter, for instance, should serve as a stimulus for the sustainable development of products that aim to take advantage of these natural resources.

Connaraceae: An updated overview of research and the pharmacological potential of 39 species

ETHNOPHARMACOLOGICAL RELEVANCE

An interdisciplinary scientific investigation of biologically active agents is fundamental to search for natural substances with therapeutic action. This review collected the most relevant information on traditional knowledge related to the use of plants of the Connaraceae family. This work is the first to compile all the published ethnobotanical, chemical, pharmacological, and toxicological information about this important plant family.

AIM OF THE STUDY

Our objective was to provide the scientific community with an up-to-date overview of the pharmacological potential of Connaraceae species.

MATERIAL AND METHODS

We searched NCBI Pubmed Central, Google Scholar, Scientific Electronic Library Online (SciELO), ScienceDirect, SciFinder, and Scopus databases to review the research on ethnobotanical, chemical, pharmacognostical, pharmacological, and toxicological studies with Connaraceaes. Books that address the theme were also included.

DISCUSSION AND CONCLUSION

The literature review indicated that 39 species of Connaraceaes have pharmacological potentiality. Ethnobotany reports listed 36 of the 39 species discussed. Pharmacognostical studies have been conducted with 23 species and isolates, and chemical compounds have been identified for only 15 species. At least one study has been published concerning the pharmacological activities for 20 of the 39 species analyzed. For Agelaea pentagyna, Cnestis ferruginea, Connars suberosus, and Rourea minor, pharmacological activity experiments were performed using isolated compounds, which have the highest current pharmacological potential. Studies employing a toxicological approach cover only 10 of the 39 Connaraceaes species. Thus, scientific community should conduct much more research for a broader understanding of this plant family.

Susceptibility of virulent and resistant Escherichia coli strains to non-polar and polar compounds identified in Microplumeria anomala

Background and Aim

Escherichia coli is one of the main pathogens responsible for veterinary and human infections, and it is associated with significant economic losses in the livestock, as it causes severe diseases to humans, particularly in children. For that reason, there is a need for introducing new drugs to treat E. coli diseases. The Brazilian species richness is a source of potential new antibacterial natural products. The study aimed at the biological and chemical investigation of the organic extract obtained from the stem of Microplumeria anomala (Apocynaceae), EB127, as it was identified as a potential source of new antibacterial compounds to be used in Veterinary.

Materials and Methods

The antibacterial activity was evaluated by disk diffusion and microdilution assays; chromatography, nuclear magnetic resonance spectrometry, and mass spectrometry were used in the isolation and identification of compounds.

Results

EB127 showed activity against E. coli ATCC25922, and against three E. coli strains that were isolated from frigarte's cloaca, named 31/1A, 35A, and 51A. Lupeol, 3-acetyl-11-oxo-β-amyrin, 3-acetyl-11-oxo-α-amyrin, sitosterol, stigmasterol, 3β,7α-dihydroxy-cholest-5-ene, 3β-hydroxy-cholest-5-en-7-one, and 3β-hydroxy-cholest-5,22-dien-7-one were identified in fraction Hex/CHCl₃, while loganin, loganic acid, methylanomaline, and anomaline were all identified in EB127 and protocatechuic acid hexoside, ferulic acid, secoxyloganin, feruloylquinic acid, vanillic acid hexoside, protocatechuic acid-4-O-β-hexoside, and rosmarinic acid were tentatively identified in fraction 10%ACN/H₂O. E. coli 51A (virulent/non-resistant) showed sensitivity to the antibacterial action of fraction Hex/CHCl₃ which contains alkaloids, triterpenes, and steroids, while E. coli 35A (resistant/non-virulent) were more susceptible to 10%ACN/H₂O, which contains iridoids as loganin and loganic acid, and glycosylated and non-glycosylated caffeic acids.

Conclusion

Fraction 10%ACN/H₂O is of interest in pursuing new drugs to treat resistant E. coli, in veterinary. All compounds were isolated from the plant for the first time and have shown potential as new antibacterial natural products from Amazon plants to be used in veterinary and human diseases.

Natural products in endodontics

Herbal remedies are used throughout the world, either in earlier or in recent times. The number of studies on this alternative therapeutic system increased in the last decades. In this paper, the relevant literature on the use of natural products in root canal therapy is revised from a MEDLINE database search. The uses of medicinal plants in endodontics include cleaning and disinfection of root canals, intracanal medicaments between appointments, sealer cements, and for removal of obturation material. Other studies showed the effect of natural products in pulpal and dentin repair. Their use is anecdotal, and their effectiveness showed to be variable and is always compared to the chemical standards currently being used. Alkaloids, coumarins, saponins, and flavonoids are aromatic substances that are produced by plants and evaluated for their therapeutic potential. Further investigation into benefits of natural products is warranted.

Antibacterial effects and cytotoxicity of an adhesive containing low concentration of silver nanoparticles

OBJECTIVES

To evaluate the antibacterial effects, cytotoxicity and microtensile bond strength of an adhesive containing low concentrations of silver nanoparticles (NAg).

METHODS

Various concentrations of NAg (50, 100, 150, 200 and 250 ppm) were incorporated into the primer of the Scotchbond Multi-Purpose adhesive system (SBMP). Antibacterial activity was examined using a broth microdilution assay to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), agar diffusion assay and the MTT assay was used to examine the biofilm metabolic activity (S. mutans). The Microtensile Bond Test (μTBS) was performed after 24 h, followed by 6-months storage in distilled water. Cytotoxicity was assessed with an MTT reduction assay in human dental pulp stem cells viability after exposure to Nag-conditioned culture media during 0, 24, 48, and 72 h. The results were statistically analyzed (α ≤ 0.05).

RESULTS

MIC was found between NAg 25 and 50 ppm MBC was determined at 50 ppm of NAg. Bacterial activity inhibition was higher than control in all NAg groups compared to control in agar diffusion assay. Biofilm inhibition was statistically higher in 250 ppm NAg than control. All NAg groups and SBMP presented similar cytotoxicity in each period. Adhesives with NAg 200 and 250 ppm and SBMP (control) presented the highest μTBS values, similar to that of SBMP control, in both instances (24 h and 6 months) (p > 0.05).

CONCLUSIONS

The commercial primer containing NAg 250 ppm showed both antibacterial effect and reliable bond strength with no cytotoxicity increase. The addition of NAg to primers seems promising for the improvement of conventional dental adhesives efficacy.

CLINICAL SIGNIFICANCE

The addition of low concentrations of NAg (250 ppm) to primers were effective to improve antibacterial effect preserving the bond strength and the biocompatibility of the commercial product. NAg/primer association could protect the tooth-adhesive interface increasing dental restoration longevity.

Characterization of phenolic compounds in tincture of edibleNepeta nuda: development of antimicrobial mouthwash

The activity of edibleNepeta nudaL. (Lamiaceae) tincture and Listerine towards a selected group of oral pathogenic microorganisms (4 bacterial and 9 fungal strains) has been explored.

Mice Behavioral Phenotype Changes after Administration of Anani (Symphonia globulifera, Clusiaceae), an Alternative Latin American and African Medicine

Background:

Anani, (Symphonia globulifera, Clusiaceae), known as chewstick, is a traditional plant occurring in Africa and in Central and South Americas that is used against parasites and microorganisms. Although its use is popular in some of these countries, there is a lack of information related to its influence over behavioral phenotype (BP).

Objective:

The objective of this study is to evaluate the influence of the administration of the extract obtained from the aerial organs of Anani (EB1257) to male Balb-c mice over BP.

Materials and Methods:

Open cage observation, open field, and elevated-plus maze apparatuses were used. Evaluations were done 15, 30, 60, 120, and 180 min after intraperitoneal administration of Anani extract.

Results:

Impairment of general behavior activity, response to touch, tail squeeze, defecation, locomotion and rearing frequency were observed although no signs of hemorrhage or macroscopical alterations of internal organs. Anani is harmful, but not toxic if used in the appropriate doses, yet to be determined to male mice. Impairment of locomotion and defecation was observed, indicating some degree of influence over locomotion, but no alterations in anxiety levels were assessed. Three compounds were previously found in the plant-lupeol (1), β-amyrin (2) and 3-β-hydroxyglutin-5-ene (3), and one is being described for the first time to occur in the species: oleanolic acid (4).

Conclusions:

The present work contributes in the support of the rational use of Anani, an important Latin American and African alternative medicine, presenting findings that are being reported for the first time.

SUMMARY

Symphonia globulifera impairs locomotion and defecatin in behavior analyses

No alterations in anxiety was observed

Oleanolic acid occurs in the species.

Abbreviations used: BP: Behavioral phenotype; OF: Open field, EPM: Elevated-plus maze, MMA/ICMBio/SISBIO: Ministério do Meio Ambiente/Instituto Chico Mendes de Conservação da Biodiversidade/Sistema de Autorização e Informação em Biodiversidade, IBAMA/MMA/CGen: Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis/Ministério do Meio Ambiente/Conselho de Gestão do Patrimônio Genético, AM: Amazonas State, UNIP: Universidade Paulista, mg: milligram, kg: kilogram, I.P: Intraperitoneal, CEUA/ICS/UNIP: Comissão de Ética no Uso de Animais/Instituto de Ciências da Saúde/Universidade Paulista, LD: Lethal dose, NLD: Nonlethal dose, GBA: General behavior activity, FCHCL₃: Fraction chloroform, FBuOH: Fraction buthanol, FH₂O: Fraction water, FrHEX: Fraction hexane, FrDCM: Fraction dichloromethane, FrMeOH: Fraction methanol, ¹³C NMR: Carbon nuclear magnetic resonance, EPA: United States Environmental Protection Agency.

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

This study reports for the first time promising antibacterial and antifungal effects of epidihydropinidine, the major piperidine alkaloid in the needles and bark of Norway spruce, Picea abies (L.) Karsten. Epidihydropinidine was growth inhibitory against all bacterial and fungal strains used in our investigation, showing the lowest MIC value of 5.37μg/mL against Pseudomonas aeruginosa, Enterococcus faecalis, Candida glabrata and C. albicans. Epidihydropinidine was nearly three times more active than tetracycline against P. aeruginosa and E. faecalis. Promising antibacterial effects were also recorded against Staphylococcus aureus and Bacillus cereus (MIC 10.75μg/mL) as well as against Salmonella enterica (MIC and MBC 43μg/mL). Our preliminary results suggest that epidihydropinidine as well related alkaloids of Norway spruce could be powerful candidates for new antibiotics and for preventing food spoilage.

Antibacterial Efficacy of Neem (Azadirachta indica) Extract against Enterococcus faecalis: An in vitro Study

INTRODUCTION

Debridement and disinfection of the root canal is a crucial step in the success of endodontic treatment. Several antimicrobial agents alone or in combination are used to achieve this. The objective of this in vitro study was to assess the antimicrobial efficacy of neem (Azadirachta indica) extract against Enterococcus faecalis.

MATERIALS AND METHODS

Neem leaf extract, 2% chlorhexidine, 3% sodium hypochlorite were used to assess the antimicrobial efficiency. Agar well diffusion test was used to study the antimicrobial efficacy with saline as control. The zone of inhibition was recorded, tabulated, and analyzed statistically with the help of IBM Statistical Package for the Social Sciences statistics version 20 using analysis of variance test.

RESULTS

All the three medicaments showed well-defined and comparable zones of inhibition around their respective wells. All values were significantly higher than the control group. Analysis of variance showed significant difference between zone diameters of chlorhexidine, neem leaf extract, and 3% sodium hypochlorite against E. faecalis (p < 0.05).

CONCLUSION

From the present study, it can be concluded that neem leaf extract shows comparable zones of inhibition with that of chlorhexidine and sodium hypochlorite.

CLINICAL SIGNIFICANCE

Neem leaf extract has significant antimicrobial activity against E. faecalis and thus opens the perspectives for the use of neem extract as an intracanal medication.

The Sensitivity of Endodontic Enterococcus spp. Strains to Geranium Essential Oil

Enterococci are able to survive endodontic procedures and contribute to the failure of endodontic therapy. Thus, it is essential to identify novel ways of eradicating them from infected root canals. One such approach may be the use of antimicrobials such as plant essential oils. Enterococcal strains were isolated from endodontically treated teeth by standard microbiological methods. Susceptibility to antibiotics was evaluated by the disc-diffusion method. The minimal inhibitory concentration (MIC) of geranium essential oil was investigated by microdilution in 96-well microplates in Mueller Hinton Broth II. Biofilm eradication concentrations were checked in dentin tests. Geranium essential oil inhibited enterococcal strains at concentrations ranging from 1.8-4.5 mg/mL. No correlation was shown between resistance to antibiotics and the MICs of the test antimicrobials. The MICs of the test oil were lower than those found to show cytotoxic effects on the HMEC-1 cell line. Geranium essential oil eradicated enterococcal biofilm at concentrations of 150 mg/mL. Geranium essential oil inhibits the growth of endodontic enterococcal species at lower concentrations than those required to reach IC50 against the HMEC-1 cell line, and is effective against bacteria protected in biofilm at higher concentrations. In addition, bacteria do not develop resistance to essential oils. Hence, geranium essential oil represents a possible alternative to other antimicrobials during endodontic procedures.

The influence of Brazilian plant extracts on Streptococcus mutans biofilm

Nineteen plant extracts obtained from plants from the Brazilian Amazon showed activity against planktonic Streptococcus mutans, an important bacterium involved in the first steps of biofilm formation and the subsequent initiation of several oral diseases.

OBJECTIVE

Our goal was to verify whether plant extracts that showed activity against planktonic S. mutans could prevent the organization of or even disrupt a single-species biofilm made by the same bacteria.

MATERIAL AND METHODS

Plant extracts were tested on a single-bacteria biofilm prepared using the Zürich method. Each plant extract was tested at a concentration 5 times higher than its minimum inhibitory concentration (MIC). Discs of hydroxyapatite were submersed overnight in brain-heart infusion broth enriched with saccharose 5%, which provided sufficient time for biofilm formation. The discs were then submersed in extract solutions for one minute, three times per day, for two subsequent days. The discs were then washed with saline three times, at ten seconds each, after each treatment. Supports were allowed to remain in the enriched medium for one additional night. At the end of the process, the bacteria were removed from the discs by vortexing and were counted.

RESULTS

Only two of 19 plant extracts showed activity in the present assay: EB1779, obtained from Dioscorea altissima, and EB1673, obtained from Annona hypoglauca. Although the antibacterial activity of the plant extracts was first observed against planktonic S. mutans, influence over biofilm formation was not necessarily observed in the biofilm model. The present results motivate us to find new natural products to be used in dentistry.

Phytochemical screening, antioxidant and antibacterial activities of extracts prepared from different tissues of Schinus terebinthifolius Raddi that occurs in the coast of Bahia, Brazil

BACKGROUND

Schinus terebinthifolius is widely used in traditional medicine by Brazilian quilombola and indigenous communities for treatment of several diseases. Extracts from different tissues are being used to produce creams to treat cervicitis and cervicovaginitis. However, most studies are limited to the assessment of the essential oils and extracts obtained from the leaves.

OBJECTIVE

The aim was to evaluate antioxidant and antibacterial activities, to assess the phytochemical profile and to quantify total phenolic compounds of various extracts prepared from S. terebinthifolius grown in the coast of Bahia, Brazil.

MATERIALS AND METHODS

Extracts were obtained by hot continuous extraction (soxhlet) and by maceration. Quantification of phenolic compounds was performed using the Folin-Ciocalteu method and antioxidant properties were assessed by 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay. Phytochemical screening was performed as described by in the literature and antibacterial activity against Enterococcus faecalis (ATCC 29212) was determined by the microdilution broth assay.

RESULTS

Extraction method greatly affected the metabolite profile of the extracts. Antioxidant activity varied between 21.92% and 85.76%, while total phenols ranged between 5.44 and 309.03 mg EAG/g of extract. Leaf extract obtained with soxhlet showed minimum inhibitory concentration (MIC) of 15.62 μg/mL, while stem extract obtained by maceration was able to inhibit the growth of E. faecalis at 62.5 μg/mL. Stem bark extracts showed a MIC of 500 μg/mL for both extraction methods, while no inhibition was observed for fruit extracts.

CONCLUSION

In general, total phenolic content, antioxidant and antibacterial activities were higher in samples obtained by soxhlet. Our results provide important clues in order to identify alternative sources of bioactive compounds that can be used to develop new drugs.

Anti-Streptococcal activity of Brazilian Amazon Rain Forest plant extracts presents potential for preventive strategies against dental caries

Caries is a global public health problem, whose control requires the introduction of low-cost treatments, such as strong prevention strategies, minimally invasive techniques and chemical prevention agents. Nature plays an important role as a source of new antibacterial substances that can be used in the prevention of caries, and Brazil is the richest country in terms of biodiversity.