scholarly journals Anin vitrostudy of the antimicrobial activity of some endodontic medicaments and their bases using an agar well diffusion assay

2009 ◽  
Vol 54 (2) ◽  
pp. 141-146 ◽  
Author(s):  
B Athanassiadis ◽  
PV Abbott ◽  
N George ◽  
LJ Walsh
Author(s):  
Pooja Suryawanshi ◽  
G.M. Vidyasagar

In the present study the antimicrobial activity of chloroform and methanolic extracts of Opuntiacochenillifera for both cladode and fruits was investigated. Methanolic extract was found to be an effective against the microbes namely, E. coli,Bacillus subtilis,Staphylococcus aureus, Pseudomonas aeruginosaCandidaalbicanC.glabrataC.haemuloniiC.Tropicalis. Maximum activity was observed against E. coli, B. Subtilisand,C.albican and C.glabrata at 40mg/ml. Agar well diffusion assay was used to determine minimum inhibitory concentration of all test microorganisms.


2021 ◽  
pp. 10-15
Author(s):  
Miloud M. Miloud ◽  
Najma A. Senussi

The present study was aimed to investigate the antimicrobial potential of leaf extracts of Euphorbia paralias and Melilotus sulcatus against four bacterial species Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Klebsiella sp. and two fungal species Asperigillus niger and Aspergillus flavus. The agar well diffusion assay was used to evaluate the antimicrobial activity. The effect of these extracts was most effective against the bacterial species compared to the fungal species at a used concentration (100 mg/ml). Methanolic extracts of selected plants displayed good antimicrobial activity against all tested microorganisms species, while, no activity for aqueous extracts against tested fungal species. Methanolic extracts were the most effective plant extracts against all tested bacterial species, with MIC and MBC reached 6.2 and 12.5 mg/ml, except Klebsiella sp. which was less sensitive to M. sulcatus methanolic extract and its MIC and MBC reached 12.5 and 25 mg/ml, respectively. These plant extracts which proved to be potentially effective can be used as bioactive agents to control microorganisms caused for diseases and they can be used naturally in the human and veterinary healthcare systems.


2020 ◽  
Vol 51 (2) ◽  
pp. 500-507 ◽  
Author(s):  
Kadhum & Hussein

This study was aimed to biosynthesized silver nanoparticles by Streptococcus pyogenes bacteria and its antimicrobial activity against (S.aureus ,P. aeruginosa, E.coli, and C. albicans yeast) at different  concentrations (20, 40, 60 ,80 and 100)  μg/ml by agar  well  diffusion  assay. Fifty sample was collected from Wounds and burns, from Baghdad Teaching City Medicine Laboratories. Samples identified by culture, VITEK 2 Compact system ID-YST kit. The sensitivity of bacterial isolates to antibiotics ware tested and the microbes were more  sensitive,  resistant  and  moderate  range to antibiotics. Several techniques where used to characterize AgNPs: X-ray Diffraction (XRD), UV–Visible Spectroscopy(UV) and Scanning electron microscope (SEM).The results show that biosynthesized silver nanoparticles are more effective than bacterial supernatant on human pathogenic microbes.


Antibiotics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 181 ◽  
Author(s):  
Doaa Safwat Mohamed ◽  
Rehab Mahmoud Abd El-Baky ◽  
Tim Sandle ◽  
Sahar A. Mandour ◽  
Eman Farouk Ahmed

Silver is a potent antimicrobial agent against a variety of microorganisms and once the element has entered the bacterial cell, it accumulates as silver nanoparticles with large surface area causing cell death. At the same time, the bacterial cell becomes a reservoir for silver. This study aims to test the microcidal effect of silver-killed E. coli O104: H4 and its supernatant against fresh viable cells of the same bacterium and some other species, including E. coli O157: H7, Multidrug Resistant (MDR) Pseudomonas aeruginosa and Methicillin Resistant Staphylococcus aureus (MRSA). Silver-killed bacteria were examined by Transmission Electron Microscopy (TEM). Agar well diffusion assay was used to test the antimicrobial efficacy and durability of both pellet suspension and supernatant of silver-killed E. coli O104:H4 against other bacteria. Both silver-killed bacteria and supernatant showed prolonged antimicrobial activity against the tested strains that extended to 40 days. The presence of adsorbed silver nanoparticles on the bacterial cell and inside the cells was verified by TEM. Silver-killed bacteria serve as an efficient sustained release reservoir for exporting the lethal silver cations. This promotes its use as a powerful disinfectant for polluted water and as an effective antibacterial which can be included in wound and burn dressings to overcome the problem of wound contamination.


Author(s):  
Savan Donga ◽  
Pooja Moteriya ◽  
Sumitra Chanda

Objectives: The aim of the present study was to evaluate antibacterial and synergistic antimicrobial properties of leaf, stem and bark of Pterocarpus santalinus. Methods: The extraction was done by decoction method. The antimicrobial activity was done by agar well diffusion assay and the synergistic antimicrobial activity was done by agar disc diffusion assay.  Results: The synergistic activity was studied with plant extracts plus antibiotics viz. Ampicillin , Polymyxin-B,  Clotrimazole and  Fluconazole.  Conclusions: Amongst the three parts, the best antimicrobial activity was shown by bark extract. All the three parts showed synergistic antimicrobial activity with antibiotics but their level varied.  The results suggest that all the three parts phytochemicals that enhance the antimicrobial efficacy of the antibiotics against some microorganisms and hence can be developed as a new therapeutic weapon against infectious diseases.


2020 ◽  
Vol 9 (4) ◽  
pp. e27942662
Author(s):  
Patrícia Capellato ◽  
Cláudia Eliana Bruno Marino ◽  
Gilbert Silva ◽  
Lucas Victor Benjamim Vasconcelos ◽  
Rodrigo Perito Cardoso ◽  
...  

During the last decades, researchers have been growing the interest in surface treatment with an antimicrobial agent. Silver nanoparticles (AgNPs) are widely used in biomedical fields due to their potent antimicrobial activity. So, in this study was investigated silver particles (isles) coated on titanium surface for dental and orthopedic application. Silver particles coating process on titanium surface were performed via sputtering that is a plasma-assisted deposition technique with and titanium without treatment was applied as comparing standard. Plasma treatment parameters were optimized so that the result was not a thin film of Ag but dispersed particles of Ag on the Ti-cp surface. The alloy surfaces were investigated using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). In order to investigate antibacterial potential Staphylococcus aureus and Escherichia coli have been used at Agar diffusion assay. The results were analyzed by analysis of variance (ANOVA) in order to verify significant difference antimicrobial activity between samples that have shown no difference between the surfaces studied treatments. For silver deposition scattered particles (isles) over titanium surface for a 10-minute treatment, EDS revealed by silver clusters that the particles were not properly scattered onto surface, hence, the low effectiveness in antibacterial activity.


2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Mashooq Ahmad Bhat ◽  
Mohamed A. Al-Omar ◽  
Ahmed M. Naglah ◽  
Abdul Arif Khan

A series of pyrazoles derived from the substituted enaminones were synthesized and were evaluated for antimicrobial activity. All the compounds were characterized by the spectral data and elemental analysis. The synthesized compounds were initially screened for their antimicrobial activity against ATCC 6538, NCTC 10400, NCTC 10418, and ATCC 27853. During initial screening, compounds (P1, P6, and P11) presented significant antimicrobial activity through disc diffusion assay. These compounds were further evaluated for antimicrobial activity at different time points against Gram-positive and Gram-negative bacteria and presented significant activity for 6 hours. The activity was found to be greater against Gram-positive bacteria. In contrast at 24 hours, the activity was found only against Gram-positive bacteria except compound (P11), showing activity against both types of bacteria. Compound (P11) was found to have highest activity against both Gram-positive and Gram-negative bacteria.


Molecules ◽  
2018 ◽  
Vol 23 (8) ◽  
pp. 2077 ◽  
Author(s):  
Ilioara Oniga ◽  
Cristina Pușcaș ◽  
Radu Silaghi-Dumitrescu ◽  
Neli-Kinga Olah ◽  
Bogdan Sevastre ◽  
...  

The biological properties and main phenolic compounds of the O. vulgare L. ssp. vulgare extract are described in the present paper. The polyphenolic compounds were analyzed by chromatographic and spectrophotometric techniques. The antioxidant potential was evaluated using several methods: CUPRAC (cupric ion reducing antioxidant capacity), FRAP (ferric reducing ability of plasma), inhibition of lipid peroxidation catalyzed by cytochrome c, and superoxide (SO) scavenging assays. The antimicrobial activity of the oregano extract was evaluated by means of agar-well diffusion assay. The hepatoprotective effect of the O. vulgare extract on CCl4-induced hepatotoxicity was evaluated in rats. Liver injury was estimated by determination of alanine aminotransaminase (ALT), aspartate aminotransaminase (AST), gamma-glutamyl transferase GGT, total protein and albumin concentrations, glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD) and malondialdehyde (MDA). These values were improved by the administration of oregano extract. A specific phenolic profile was evidenced by these data, with large amounts of rosmarinic and chlorogenic acids. The oregano extract showed very strong antioxidant activity in good agreement with the phenolic content. Antimicrobial activity was good, especially against Salmonella enteritidis and Aspergillus niger strains. The high hepatoprotective, antioxidant and antimicrobial activity, along with polyphenol-rich content, can support the use of O. vulgare in therapy. We also expect our results to open new research directions for designing important new drug products, using indigenous plant material.


2001 ◽  
Vol 64 (2) ◽  
pp. 189-194 ◽  
Author(s):  
R. UNAL ◽  
H. P. FLEMING ◽  
R. F. McFEETERS ◽  
R. L. THOMPSON ◽  
F. BREIDT ◽  
...  

Novel agar diffusion and broth dilution assays were developed for quantitatively estimating the antimicrobial activity of fresh garlic juice. Bacteria found to be inhibited by garlic juice in agar diffusion assay included two gram-positive and five gram-negative species. Leuconostoc mesenteroides was not inhibited. Escherichia coli B-103 (HB101, with pJH101, ampicillin resistant, 100 μg ml−1) was inhibited and chosen as the standard culture for quantitative assays. The agar diffusion assay was based on the slope ratio method, where the slope of dose response for garlic juice was divided by the slope of dose response for methylmethane thiosulfonate (MMTSO2). Juice from fresh garlic varied in activity between 1.76 and 2.31 μg of MMTSO2 per mg of garlic juice. The activity of juice decreased during 11 months of storage of garlic cloves at 5°C from 2.31 to less than 0.1 μg of MMTSO2 per mg of juice. The broth dilution assay also used the E. coli B-103 culture, which permitted selective enumeration of this bacterium when 100 μg ml−1 of ampicillin was incorporated into the enumerating agar. Selective enumeration was essential since the garlic juice was not sterile and, thus, contained natural flora. Growth of E. coli was unaffected by 0.1%, delayed by 0.25%, and completely inhibited at 0.5 and 2% garlic juice in broth during 24 h of incubation at 37°C. The minimum inhibition concentration of garlic juice by broth dilution assay was, thus, estimated to be 0.5%, which is equivalent to 3.46 μg of MMTSO2 per mg of garlic juice by the agar diffusion assay.


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