scholarly journals ANTIBACTERIAL AND ANTIBIOFILM ACTIVITY OF QUERCUS INFECTORIA GALLS ON ROTHIA DENTOCARIOSA ISOLATED FROM DENTAL CARIES

Author(s):  
AMBULKAR S ◽  
TALE V ◽  
KHILARI S ◽  
PAWAR J

Objective: The present study aimed to study Quercus infectoria gall extract for phytochemical analysis, antibacterial, and antibiofilm activity against Rothia dentocariosa isolated from dental caries. Methods: R. dentocariosa was isolated, characterized, and identified by 16S rRNA sequence and also checked for biofilm formation ability. Phytochemical analysis of Q. infectoria aqueous gall extracts was carried out. Antibacterial and antibiofilm activity was performed using agar well diffusion method and microtiter plate assay, respectively. Results: Bacterial isolate from dental caries was identified as R. dentocariosa by 16s rRNA sequencing technique with accession number MH824681 obtained from NCBI. Phytochemical analysis of Q. infectoria aqueous gall extract revealed the presence of alkaloids, phenol, tannin, glycosides, phenolic compound, and flavonoids. Significant antibacterial activity was observed with 19.00 (±7.07) mm diameter zone of inhibition. The biofilm inhibition assay was performed by microtiter plate method indicated 92.89% inhibition of bacteria at the concentration of 100 mg/mL of aqueous extract. Conclusion: The results indicated the efficacy of Q. infectoria gall extracts that could be explored as an alternative to current treatment.

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Muhammad Hussnain Siddique ◽  
Bilal Aslam ◽  
Muhammad Imran ◽  
Asma Ashraf ◽  
Habibullah Nadeem ◽  
...  

Antibiotic resistance against present antibiotics is rising at an alarming rate with need for discovery of advanced methods to treat infections caused by resistant pathogens. Silver nanoparticles are known to exhibit satisfactory antibacterial and antibiofilm activity against different pathogens. In the present study, the AgNPs were synthesized chemically and characterized by UV-Visible spectroscopy, scanning electron microscopy, and X-ray diffraction. Antibacterial activity against MDR K. pneumoniae strains was evaluated by agar diffusion and broth microdilution assay. Cellular protein leakage was determined by the Bradford assay. The effect of AgNPs on production on extracellular polymeric substances was evaluated. Biofilm formation was assessed by tube method qualitatively and quantitatively by the microtiter plate assay. The cytotoxic potential of AgNPs on HeLa cell lines was also determined. AgNPs exhibited an MIC of 62.5 and 125 μg/ml, while their MBC is 250 and 500 μg/ml. The production of extracellular polymeric substance decreased after AgNP treatment while cellular protein leakage increased due to higher rates of cellular membrane disruption by AgNPs. The percentage biofilm inhibition was evaluated to be 64% for K. pneumoniae strain MF953600 and 86% for MF953599 at AgNP concentration of 100 μg/ml. AgNPs were evaluated to be minimally cytotoxic and safe at concentrations of 15-120 μg/ml. The data evaluated by this study provided evidence of AgNPs being safe antibacterial and antibiofilm compounds against MDR K. pneumoniae.


2021 ◽  
Vol 9 (09) ◽  
pp. 165-173
Author(s):  
Gujjari Sreehitha Pratap ◽  

The Aegle marmelos commonly known as BAEL belongs to family Rutaceae plays a role in traditional culture and medication from ancient periods. This plant lacks sufficient evidences regarding the values and components it has. Therefore, we framed out our studies to evaluate the phytochemical analysis, antibacterial activity, antibiofilm activity. These studies are evaluated using different solvents like methanol, acetone, chloroform, toluene leaf extracts of Aegle marmelos. We evaluated the potency of different solvents leaf extracts using Agar well diffusion method. Antibacterial activity was also evaluated using ELISA plate assay. The potency of different solvents extracts to inhibit biofilm of selected microbial strains. In accordance to results, the leaf extracts revealed the presence of several biologically active phytochemicals with highest quantities of carbohydrates, phenols, alkaloids, flavonoids, tannins, saponins, steroids, aminoacids etc. The antibacterial activity was found significant against microbial strains of both gram positive and gram negative bacteria. These strains showed susceptibility nature towards the different solvents extracts with zone of inhibitions (mm). On the other hand, the inhibition of biofilm was also significant at all tested concentrations. The biofilm inhibition of microbial strains was found significant at 1 XMIC, 2 XMIC, 3 XMIC. Based on our studies here we conclude that the different solvents leaf extracts possessed inhibitory activity against selected human pathogenic organisms.


2021 ◽  
Author(s):  
Ewa Jasińska ◽  
Agnieszka Bogut ◽  
Agnieszka Magryś ◽  
Alina Olender

Abstract Purpose: Determination of the association between ica genes and phenotypic biofilm formation in staphylococcal isolates involved in conjunctivitis, their antibiotic resistance as well as detection of selected virulence characteristics: adhesion to epithelial cells and in vitro cytotoxicity.Methods: The study included 26 Staphylococcus aureus (SA) and 26 Staphylococcus epidermidis (SE) isolates. The presence of icaAD genes and ica operon was determined by the PCR assay. Phenotypic biofilm formation was verified using the microtiter plate assay. Antibiotic resistance was performed using the disc diffusion method. Staphylococcal ability to attach to host cells was assessed by flow cytometry. Cytotoxicity on epithelial cells was evaluated by LDH assay.Results: The ica genes were detected in 26.9% of SE and in 42.3% of SA isolates. Only 15.3% of isolates (SE) were positive for both the icaAD and the ica operon. Phenotypically, 19.2% of SE isolates were strong biofilm producers, among which three were both icaAD- and ica operon-positive. 26.9% of SA isolates were strong biofilm producers. Methicillin resistance (MR) was detected in 34.6% of SE and 26.9% of SA isolates. 75% of MR isolates were multidrug resistant. SA isolates adhered to host cells more extensively than SE. SA isolates released higher level of LDH than SE.Conclusions: Adherence abilities were commonly observed in staphylococci associated with conjunctivitis. However, low prevalence of isolates positive for a complete and functional ica locus and low prevalence of strong biofilm producers was detected. SA adhered to a greater extent to eukaryotic cells than SE and were more cytotoxic.


2020 ◽  
Vol 10 (2) ◽  
pp. 48
Author(s):  
Sri Kunarti ◽  
Aulia Ramadhani ◽  
Laskmiari Setyowati

Background: Dental caries is one of the most common infectious diseases and often occurs in the community caused by bacteria. Attached bacteria in the tooth surface for a long time will form a biofilm and will lead to demineralization characterized by damage in the structure of the tooth enamel. The bacteria that cause dental caries and can form biofilms is Streptococcus mutans. The bacteria inside biofilms are more resistant to antibacterial agents. Flavonoids in mangosteen pericarp extract can be a cleaner alternative for the anti-biofilm cavity that has properties against Streptococcus mutans. Purpose: To determine the activity of flavonoids in mangosteen pericarp extract at a certain concentration against Streptococcus mutans bacteria. Methods: This study was a laboratory experimental study with a post-test only control group design. Streptococcus mutans were diluted according to the Mc Farland dilution standard 106 in Tryptic Soy Broth (TSB) medium and put in a flexible U-bottom microtiter plate. Then it was incubated for 5x24 hours and checked using crystal violet simple staining to see the formation of biofilms. Flavonoid extract of mangosteen pericarp performed serial dilution in a concentration of 100%, 50%, 25%, 12.5%, 6.25%, 3.125%, 1.56%, and 0.78% was added, and the incubation process were conducted for 1x24 hours. OD (Optical Density) readings were done with a wavelength of 595 nm. Results: There was a significant difference between the test groups and the positive control group. The concentration of 100% had the anti-biofilm activity and showed the value of the highest percentage of inhibition, whilst the concentration of 0.78% showed a minimum biofilm inhibition concentration. The results were demonstrated by a statistical analysis test. Conclusion: Flavonoid extract of mangosteen pericarp at a certain concentration has anti-biofilm activity against Streptococcus mutans biofilm.


Author(s):  
S. Mabel Parimala ◽  
A. Antilin Salomi

People use plants to treat infections, and this has led to search of antimicrobials from medicinal plants. In this work, we evaluated the ethanol extract of Syzygium cumini seeds for their antibacterial and antifungal activities. Extraction was performed by maceration method using ethanol. The antimicrobial efficacy of the extract was assessed by agar well diffusion method against ten bacterial species, Bacillus cereus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Serratia marcescens, Staphylococcus aureus and Streptococcus mutans, and five fungal species, Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Candida albicans and Mucor sp. Minimum inhibitory concentrations (MICs) of the extract were determined by resazurin microtiter plate assay.  Phytochemicals in the extract was identified by gas chromatography mass spectrometry (GC-MS) information.  In agar well diffusion method, Gram-negative bacteria such as P. aeruginosa and S. marcescens, Gram-positive bacteria such as B. subtilis and E. faecalis and fungi A. fumigatus were more susceptible showing larger zones of inhibition.  In resazurin method, low MICs were recorded for bacteria, B. cereus (<7.8 µg) and P. aeruginosa (15.6 µg) and fungi, A. fumigatus (31.2 µg).  Fifteen compounds were identified by GC-MS profiling of the extract.  The antimicrobial activity of the extract can be rightly related to the secondary metabolites in the ethanol extract of Syzygium cumini seeds.


2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Edward Ntim Gasu ◽  
Hubert Senanu Ahor ◽  
Lawrence Sheringham Borquaye

Bacteria in biofilms are encased in an extracellular polymeric matrix that limits exposure of microbial cells to lethal doses of antimicrobial agents, leading to resistance. In Pseudomonas aeruginosa, biofilm formation is regulated by cell-to-cell communication, called quorum sensing. Quorum sensing facilitates a variety of bacterial physiological functions such as swarming motility and protease, pyoverdine, and pyocyanin productions. Peptide mix from the marine mollusc, Olivancillaria hiatula, has been studied for its antibiofilm activity against Pseudomonas aeruginosa. Microscopy and microtiter plate-based assays were used to evaluate biofilm inhibitory activities. Effect of the peptide mix on quorum sensing-mediated processes was also evaluated. Peptide mix proved to be a good antibiofilm agent, requiring less than 39 μg/mL to inhibit 50% biofilm formation. Micrographs obtained confirmed biofilm inhibition at 1/2 MIC whereas 2.5 mg/mL was required to degrade preformed biofilm. There was a marked attenuation in quorum sensing-mediated phenotypes as well. At 1/2 MIC of peptide, the expression of pyocyanin, pyoverdine, and protease was inhibited by 60%, 72%, and 54%, respectively. Additionally, swarming motility was repressed by peptide in a dose-dependent manner. These results suggest that the peptide mix from Olivancillaria hiatula probably inhibits biofilm formation by interfering with cell-to-cell communication in Pseudomonas aeruginosa.


2020 ◽  
Vol 11 (1) ◽  
pp. 386-396
Author(s):  
Challaraj Emmanuel E S ◽  
Vinni Biji ◽  
Gayathri N. Krishna

A number of phytochemicals or secondary metabolites were produced by herbs and spices. These were used as food preservatives and also as traditional medicines from long back. These were having various pharmacological benefits which included antioxidant, analgesic, anticancer, anti-inflammatory and anti-pyretic properties. In the present study two different plant species (Zingiber officinale, Myristica fragrans) were used for studying their antimicrobial and antibiofilm activity. The phytochemical analysis of the plant extracts was done by using standard methodology. FTIR analysis of the ginger and nutmeg extracts were carried out to study the functional groups present in the respective plant extracts. The extracts were also subjected to NMR spectroscopy. Two different bacteria were used for the studies which are good biofilm producers, Pseudomonas and E.coli. The antimicrobial activity of the methanolic and choloroform extracts of ginger and nutmeg were studied using air liquid interphase coverslip assay and biofilm assay. The results suggest that the ginger and nutmeg extracts have biofilm inhibition activity. The reduction in biofilm was observed in all the 3 concentrations of the nutmeg chloroform extract with maximum biofilm reduction in 100% and was compared with the control. Both Pseudomonas aeruginosa and Escherichia coli, biofilm inhibition was observed in all 3 concentrations of ginger and nutmeg.


2021 ◽  
Vol 12 ◽  
Author(s):  
Renato Dantas-Medeiros ◽  
Ana Caroline Zanatta ◽  
Luanda Bárbara Ferreira Canário de Souza ◽  
Júlia Morais Fernandes ◽  
Bruno Amorim-Carmo ◽  
...  

Commiphora leptophloeos (Burseraceae) is a medicinal plant native to Brazil which is popularly used for treating oral and vaginal infections. There has been no scientific evidence pointing to its efficacy in the treatment of these infections. Thus, this study sought to investigate the cytotoxic, antifungal, and antibiofilm activity of C. leptophloeos against Candida spp. and to isolate, identify, and quantify the content of B-type oligomeric procyanidins (BDP) in the extract of C. leptophloeos stem bark. The extract and the n-butanol fraction were obtained by maceration and liquid-liquid partition, respectively. Phytochemical analysis performed by HPLC-PDA/ELSD and FIA-ESI-IT-MS/MS allowed the identification and quantification of BDP in the samples. The application of centrifugal partition chromatography helped isolate BDP, which was identified by 1H NMR and MS analyses. Candida spp. reference strains and clinical isolates (including fluconazole-resistant strains) derived from the blood cultures of candidemic patients and the vaginal secretion of patients with vulvovaginal candidiasis were used for evaluating the antifungal and antibiofilm effects. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) were determined by the microdilution technique, and biofilm inhibition was evaluated through crystal violet and XTT assays. The combined action of BDP with fluconazole was determined by the checkerboard method. The extract, the n-butanol fraction, and the BDP exhibited antifungal activity with MIC values ranging from 312.5 to 2500 μg/mL and were found to significantly reduce the biofilm formed in all the Candida strains investigated. BDP showed a fungicidal potential against strains of Candida spp. (especially against fluconazole-resistant strains), with MIC and MFC values ranging from 156.2 to 2500 μg/mL. In addition, the combined application of BDP and fluconazole produced synergistic antifungal effects against resistant Candida spp. (FICI = 0.31–1.5). The cytotoxic properties of the samples evaluated in human erythrocytes through hemolytic test did not show hemolytic activity under active concentrations. The findings of the study show that C. leptophloeos has antifungal and antibiofilm potential but does not cause toxicity in human erythrocytes. Finally, BDP, which was isolated for the first time in C. leptophloeos, was found to exhibit antifungal effect against Candida spp. either when applied alone or in combination with fluconazole.


2021 ◽  
Vol 22 (5) ◽  
Author(s):  
Elnaz Ahmadnejad ◽  
Samaneh Dolatabadi

Background: Probiotic bacteria are one of the useful dietary supplements for human health. The main reason for selecting probiotics is the lack of prolonged side effects. Objectives: This study aimed to isolate lactobacilli from traditional yogurt and cheese samples collected in Neyshabur city, Khorasan Razavi, Iran, and to characterize them using specific biochemical and molecular assays. Methods: The probiotic potency of bacteria was tested by resistance to acid, bile, NaCl, and organic acid production. Moreover, the antagonistic effects of the isolates were investigated against enteric pathogenic bacteria using the well diffusion method. Bacteriocin production was also investigated using the microtiter plate assay. Results: Four Lactobacillus spp. with > 99% homology to L. reuteri, L. plantarum, and L. acidophilus, were isolated with probiotic potency. The quantitative measurements used in the study with the statistical analysis resulted in the interpretation of good effects against Clostridium perfringens, Salmonella typhi, Staphylococcus aureus, and Listeria monocytogenes. Our isolates exhibited bile salt hydrolase activity, excellent NaCl and acid tolerance (pH = 3), and bacteriocin production. Conclusions: Our results showed that Lactobacillus strains isolated from Neyshabur traditional cheese could be considered good potential probiotic strains and had more antagonistic activity against human pathogens when compared to other samples. Their antibacterial activity was associated with both bacteriocin and organic acids production, but they should be further investigated for their human health benefits.


2021 ◽  
Author(s):  
Safar Ali Alizadeh ◽  
Amir Javadi ◽  
Farhad Nikkhahi ◽  
Mohammad Rostamani ◽  
Mehdi Bakht ◽  
...  

Background: The overused of biocides in healthcare-facilities poses risk for emergence and spread of antibiotic resistance among nosocomial pathogens. Hospital-acquired infections due to S. maltophilia particularly in the immunocompromised patients have been increased. The objective of this study was to evaluate the susceptibility of S. maltophilia clinical isolates to commonly used biocides in hospitals, as well the frequency of biocides resistance gene among them. This study also intended to assess the effect of exposure of S. maltophilia isolates to sub-inhibitory concentrations of sodium hypochlorite upon the antimicrobial susceptibility patterns. Methods: This study included 97 S. maltophilia isolates. Biofilm formation was determined by microtiter plate assay. The susceptibility tests of five biocides were studied against all S. maltophilia isolates by microbroth dilution method. Susceptibility of isolates to antibiotics by disk diffusion method were compared before and after exposure to sub-inhibitory concentrations of sodium hypochlorite. Presence of qacE, qacEΔ1, SugE genes was screened by PCR. Results: Based on minimum inhibitory and bactericidal concentrations of biocides sodium hypochlorite 5% and ethyl alcohol 70% were the strongest and weakest against S. maltophilia isolates, respectively. The frequency of sugE gene resistance genes was found to be high (90.7%) in our clinical S. maltophilia isolates. None of the isolates carried qacE and qacEΔ1 gene. Exposure to sub-inhibitory concentration of sodium hypochlorite showed significantly change the susceptibility of isolates towards ceftazidime (P = .019), ticarcillin/clavulanate (P = .009). and chloramphenicol (P = .028). Conclusions: This study demonstrated that exposure to sub-inhibitory concentration of sodium hypochlorite leads to reduced antibiotic susceptibility and development of multidrug-resistant S. maltophilia strains.


Sign in / Sign up

Export Citation Format

Share Document