scholarly journals Carbon Nanomaterials and LED Irradiation as Antibacterial Strategies against Gram-Positive Multidrug-Resistant Pathogens

2019 ◽  
Vol 20 (14) ◽  
pp. 3603 ◽  
Author(s):  
Lisa Elias ◽  
Rafael Taengua ◽  
Belén Frígols ◽  
Beatriz Salesa ◽  
Ángel Serrano-Aroca
Keyword(s):  
Antibacterial Activity ◽  
Carbon Nanomaterials ◽  
Multidrug Resistant ◽  
Gram Positive ◽  
Methicillin Resistant ◽  
Light Emitting ◽  
High Antibacterial Activity ◽  
Wide Range ◽  
Multidrug Resistant Pathogens ◽  
Led Irradiation

Background: Due to current antibiotic resistance worldwide, there is an urgent need to find new alternative antibacterial approaches capable of dealing with multidrug-resistant pathogens. Most recent studies have demonstrated the antibacterial activity and non-cytotoxicity of carbon nanomaterials such as graphene oxide (GO) and carbon nanofibers (CNFs). On the other hand, light-emitting diodes (LEDs) have shown great potential in a wide range of biomedical applications. Methods: We investigated a nanotechnological strategy consisting of GO or CNFs combined with light-emitting diod (LED) irradiation as novel nanoweapons against two clinically relevant Gram-positive multidrug-resistant pathogens: methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE). The cytotoxicity of GO and CNFs was studied in the presence of human keratinocyte HaCaT cells. Results: GO or CNFs exhibited no cytotoxicity and high antibacterial activity in direct contact with MRSE and MRSA cells. Furthermore, when GO or CNFs were illuminated with LED light, the MRSE and MRSA cells lost viability. The rate of decrease in colony forming units from 0 to 3 h, measured per mL, increased to 98.5 ± 1.6% and 95.8 ± 1.4% for GO and 99.5 ± 0.6% and 99.7 ± 0.2% for CNFs. Conclusions: This combined antimicrobial approach opens up many biomedical research opportunities and provides an enhanced strategy for the prevention and treatment of Gram-positive multidrug-resistant infections.

scholarly journals Crude extract from a hardcoral-associated bacterium Virgibacillus salarius PHC-44-04 inhibiting growth of Multidrug-Resistant Enterobacter aerogenes human pathogen

2020 ◽  
Vol 18 (2) ◽  
Author(s):  
D. Ayuningrum ◽  
SAKTI IMAM MUCHLISSIN ◽  
AGUS TRIANTO ◽  
OCKY KARNA RADJASA ◽  
AGUS SABDONO
Keyword(s):  
Antibacterial Activity ◽  
Liquid Medium ◽  
Crude Extract ◽  
Enterobacter Aerogenes ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Human Pathogen ◽  
Antibacterial Test ◽  
High Antibacterial Activity ◽  
Wide Range

Abstract. Ayuningrum D, Muchlissin SI, Trianto A, Radjasa OK, Sabdono A. 2018. Crude extract from a hardcoral-associated bacterium Virgibacillus salarius PHC-44-04 inhibiting growth of Multidrug-Resistant Enterobacter aerogenes human pathogen. Biofarmasi J Nat Prod Biochem 18: 78-83. Hardcoral-associated bacteria are potential sources of natural product compounds with wide range of activities, i.e. antibacterial activity, antiviral, anticancer, antifungal, etc. Virgibacillus salarius PHC-44-04 is a gram-positive bacterium that was isolated in prior research from hard coral Pavona sp. collected from Panjang Island, Jepara, Indonesia. This bacterium at the screening phase was showing high antibacterial activity against Multidrug-Resistant Enterobacter aerogenes (MDR-EA). Therefore, this paper has aim to deliver the result of crude extract antibacterial test from V. salarius PHC-44-04 after being cultivated in liquid medium, to know the efficiency of using supernatant and pellet extract and to determine in which concentration was the minimum for antibacterial activity. The cultivation of bacterial isolates was using liquid medium Nutrient Broth, and the production of crude extract was using liquid-liquid extraction method. The liquid medium containing bacterial cell was separated using centrifuge with 8000 rpm became supernatant and pellet. The supernatant was extracted using ethyl acetate, while the pellet was extracted using methanol. The antibacterial test from both crude extract from supernatant and pellet was using disk diffusion method with several concentration as follows: 15 µg/mL, 30 µg/mL, 60 µg/mL, 90 µg/mL, 180 µg/mL, 250 µg/mL, 350 µg/mL, and 500 µg/mL. Each concentration was repeated in three replicates. The crude extract produced from 700 mL supernatant was 0.0667 g and from 50mL pellet was 0.0320. The pellet crude extract has higher mass but not having antibacterial activity against MDR-EA. The result showed only supernatant crude extract of V. salarius showed antibacterial activity against MDR-EA bacterium. The minimal crude extract concentration to inhibit the growth of MDR-EA was 60 µg/mL, meanwhile, the best concentration for exhibiting antibacterial activity was at 500 µg/mL with zone of inhibition (ZOI) diameter of 11.77 ± 0.8730 mm. Thus, supernatant should be the main source of crude extract production rather than the pellet to get high antibacterial activity.

scholarly journals Membrane-Targeting Triphenylphosphonium Functionalized Ciprofloxacin for Methicillin-Resistant Staphylococcus aureus (MRSA)

Antibiotics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 758
Author(s):  
Sangrim Kang ◽  
Kyoung Sunwoo ◽  
Yuna Jung ◽  
Junho K. Hur ◽  
Ki-Ho Park ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Morphological Changes ◽  
Antibacterial Activities ◽  
Multidrug Resistant ◽  
Severe Problem ◽  
Methicillin Resistant ◽  
Bacterial Membranes ◽  
High Antibacterial Activity ◽  
New Antibiotics

Multidrug-resistant (MDR) bacteria have become a severe problem for public health. Developing new antibiotics for MDR bacteria is difficult, from inception to the clinically approved stage. Here, we have used a new approach, modification of an antibiotic, ciprofloxacin (CFX), with triphenylphosphonium (TPP, PPh3) moiety via ester- (CFX-ester-PPh3) and amide-coupling (CFX-amide-PPh3) to target bacterial membranes. In this study, we have evaluated the antibacterial activities of CFX and its derivatives against 16 species of bacteria, including MDR bacteria, using minimum inhibitory concentration (MIC) assay, morphological monitoring, and expression of resistance-related genes. TPP-conjugated CFX, CFX-ester-PPh3, and CFX-amide-PPh3 showed significantly improved antibacterial activity against Gram-positive bacteria, Staphylococcus aureus, including MDR S. aureus (methicillin-resistant S. aureus (MRSA)) strains. The MRSA ST5 5016 strain showed high antibacterial activity, with MIC values of 11.12 µg/mL for CFX-ester-PPh3 and 2.78 µg/mL for CFX-amide-PPh3. The CFX derivatives inhibited biofilm formation in MRSA by more than 74.9% of CFX-amide-PPh3. In the sub-MIC, CFX derivatives induced significant morphological changes in MRSA, including irregular deformation and membrane disruption, accompanied by a decrease in the level of resistance-related gene expression. With these promising results, this method is very likely to combat MDR bacteria through a simple TPP moiety modification of known antibiotics, which can be readily prepared at clinical sites.

scholarly journals Cyathea gigantea (Cyatheaceae) as an antimicrobial agent against multidrug resistant organisms

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Kathakali Nath ◽  
Anupam Das Talukdar ◽  
Mrinal Kanti Bhattacharya ◽  
Deepshikha Bhowmik ◽  
Shiela Chetri ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Antibacterial Property ◽  
Treatment Options ◽  
Multidrug Resistant ◽  
Diffusion Method ◽  
Synergistic Activity ◽  
Gram Positive ◽  
Traditional Use ◽  
Gram Negative ◽  
Multidrug Resistant Organisms

Abstract Background Rapid emergence of multidrug resistant (MDR) organisms in hospital and community settings often result into treatment failure, thus leading the clinicians with fewer treatment options. Cyathea gigantea, an ethnomedicinally important fern used in cuts and wound infections. So, if this medicinal plant is used in treating the MDR infections then it might bring certain relief in future treatment options. Methods Antibacterial activity of C. gigantea against MDR bacteria was assed using well diffusion and broth microdilution methods to determine the diameters of growth inhibition zones, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Synergistic activity was also determined with the conventional antibiotics by disc diffusion method followed by FIC index of each of the tested antibiotic was calculated. The active extract was then subjected to fractionation by column chromatography and antibacterial activity was done with each of the collected fractions. Results Crude extract of C. gigantea was found to be active against all the tested organisms. The MIC was 200 μg/ml against Gram-positive i.e., Staphylococcus aureus ATCC 25923 and 400 μg/ml against Gram-negative i.e., Escherichia coli ATCC 25922 and Pseudomonas aeruginosa PAO1, while the MBC was 400 μg/ml in case of Gram-positive and 800 μg/ml for Gram-negative. The synergistic activity revealed that the plant extract increased the antibacterial property of the studied antibiotics and the FIC index showed that significant synergistic activity was shown by ciprofloxacin followed by tetracycline, ampicillin and oxacillin. Antibacterial activity with the fractionated extract showed that the FR II, FR III and FR IV were active against both Gram-positive and Gram-negative bacteria, whereas FR I, FR V and FR VI did not show antibacterial property against any of the tested bacteria. Conclusions Extracts of C. gigantea was found active against both selected Gram-positive and Gram-negative organisms and thus offers the scientific basis for the traditional use of the fern. The present study also provides the basis for future study to validate the possible use against multidrug resistant organisms.

scholarly journals Comparative In Vitro Activities of Daptomycin and Vancomycin against Resistant Gram-Positive Pathogens

2000 ◽  
Vol 44 (12) ◽  
pp. 3447-3450 ◽  
Author(s):  
D. R. Snydman ◽  
N. V. Jacobus ◽  
L. A. McDermott ◽  
J. R. Lonks ◽  
J. M. Boyce
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Streptococcus Pneumoniae ◽  
Calcium Concentration ◽  
In Vitro Activity ◽  
Gram Positive ◽  
Methicillin Resistant ◽  
Vancomycin Resistant ◽  
Gram Positive Cocci

ABSTRACT The in vitro activity of daptomycin against 224 current gram-positive clinical isolates including vancomycin-resistantEnterococcus faecium (VREF), methicillin-resistantStaphylococcus aureus (MRSA), methicillin-resistantStaphylococcus spp. (MRSS), and penicillin-resistantStreptococcus pneumoniae (PRSP) was evaluated. The MICs at which 90% of isolates are inhibited for daptomycin and vancomycin, respectively, were as follows: MRSA, 1 and 2 μg/ml; MRSS, 1 and 4 μg/ml; PRSP, 1 and 0.5 μg/ml; and VREF, 2 and >64 μg/ml. Daptomycin was bactericidal against 82% of 17 VREF isolates. The antibacterial activity of daptomycin was strongly dependent on the calcium concentration of the medium. Daptomycin was active against all gram-positive cocci tested.

scholarly journals Quercetin as a Precursor for the Synthesis of Novel Nanoscale Cu (II) Complex as a Catalyst for Alcohol Oxidation with High Antibacterial Activity

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Zahra Moodi ◽  
Ghodsieh Bagherzade ◽  
Janny Peters
Keyword(s):  
Antibacterial Activity ◽  
Schiff Base ◽  
Biological Activities ◽  
Schiff Base Complex ◽  
13C Nmr Spectroscopy ◽  
Inhibition Zone ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
High Antibacterial Activity

Quercetin (3,3′,4′,5,7-pentahydroxyflavone) is one of the dietary flavonoids, distributed in medicinal plants, vegetables, and fruits. Quercetin has the ability to bind with several metal ions to increase its biological activities. In the last two decades, quercetin has attracted considerable attention due to the biological and pharmaceutical activities such as antioxidant, antibacterial, and anticancer. In the present study, quercetin and ethanolamine were used for the synthesis Schiff base complex, which was characterized by IR, 1H NMR, and 13C NMR spectroscopy. The Schiff base has been employed as a ligand for the synthesis of novel nanoscale Cu (II) complex. The product was characterized by FT-IR spectroscopy, FESEM, and XRD. Significantly, the product showed remarkable catalytic activity towards the oxidation of primary and secondary alcohols. The antibacterial activity of the final product was assessed against Staphylococcus aureus (Gram‐positive) and Escherichia coli (Gram‐negative) bacteria using an inhibition zone test. The synthesized nanoscale Cu (II) complex exhibited a strong antibacterial activity against both Gram-positive and Gram-negative bacteria.

scholarly journals Antibacterial Components of Levisticum officinale Koch against Multidrug-resistant Mycobacterium tuberculosis

2020 ◽  
Vol 26 (4) ◽  
pp. 441-447
Author(s):  
Hamidreza Monsef Esfahani ◽  
Mahdi Moridi Farimani ◽  
Samad Nejad Ebrahimi ◽  
Jee Hyung Jung ◽  
Atousa Aliahmadi ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Mycobacterium Tuberculosis ◽  
Molecular Docking ◽  
Multidrug Resistant ◽  
Dilution Method ◽  
Phytochemical Analysis ◽  
Moderate Activity ◽  
Active Compounds ◽  
Methicillin Resistant ◽  
Mycobacterial Cell Wall

Background: A bioassay-guided fractionation technique was used to evaluate the active constituents of the perennial plant L. officinale W.D.J. Koch (Apiaceae) against multidrug resistant (MDR) Mycobacterium tuberculosis. Methods: Column chromatography was used to isolation of compounds from L. officinale and spectroscopic methods including 1D and 2D NMR (Nuclear magnetic resonance) and HRMS (high resolution mass spectrometry) were used to identification of the isolated compounds. Also, to evaluate antibacterial activity, minimum inhibitory concentration (MIC) was carried out by broth micro-dilution method. Finally, molecular docking (MD) was performed using the Schrödinger package to evaluate interactions between the active compounds and InhA protein. Results: Phytochemical analysis of the ethyl acetate extract of the plant roots led to isolation of bergapten (1), isogosferol (2), oxypeucedanin (3), oxypeucedanin hydrate (4), imperatorin (5), ferulic acid (6) and falcarindiol (7). Falcarindiol and oxypeucedanin indicated a moderate activity on MDR M. tuberculosis with MIC values of = 32 and 64 μg/mL, respectively. Antibacterial activity of falcarindiol was also observed against S. aureus and methicillin-resistant S. aureus strains with the MIC values of 7.8 and 15.6 μg/mL, respectively. The results of docking analysis showed a good affinity of oxypeucedanin (3) and falcarindiol (7) to InhA enzyme with docking score values of -7.764 and -7.703 kcal/mol, respectively. Conclusion: Finally, 7 compounds were isolated from L. officinale that compounds 2-6 report for the first time from this plant. On the basis of the molecular docking (MD) study, oxypeucedanin (3) and falcarindiol (7) as active compounds against M. tuberculosis may be proposed as potential inhibitors of 2-trans-enoyl-ACP reductase (InhA), a key enzyme involved in the biosynthesis of the mycobacterial cell wall. Moreover, antibacterial activity of falcarindiol against methicillin-resistant S. aureus (MRSA) was remarkable.

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