Synthesis of silver nanoparticles using Nigella sativa seed extracts and assessment of their antibacterial activity

Silver nanoparticles were biosynthesized from Nigella sativa seed extracts using ethanol and chloroform. The antibacterial activity of silver nanoparticles against some drug-resistant bacteria has been established, but further study is needed to assess whether these particles could be an option for the treatment and prevention of drug-resistant microbial infections. Synthesized nanoparticles were characterized and screened for their antibacterial properties on resistant strains. The biosynthesized silver nanoparticles were characterized by UV-Visible, FTIR, Dynamic light scattering and Scanning Electron Microscope (SEM) analysis. The antibacterial action of biosynthesized silver nanoparticles was assessed by Microtitre Broth dilution process using Ciprofloxacin as standard, against resistant strains like Pseudomonas aeruginosa, Clostridium difficile, Klebsiella pneumoniae and Streptococcus pyogenes. The Silver nanoparticles obtained from chloroform extract of Nigella sativa seeds were more effective against Pseudomonas aeuruginosa, Clostridium difficile and Streptococcus pyogenes; than ethanolic seed extracts at 120 µL. Our data propose that the silver nanoparticles are effective against a variety of drug-resistant bacteria, which makes them a potential candidate for use in pharmaceutical products that may help to treat drug-resistant pathogens in different clinical environments. The present study focuses on the ability of phytoconstituents capped with silver nitrate can be used to treat infections caused by resistant bacteria

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The interplay between size and valence state on the antibacterial activity of sub-10 nm silver nanoparticles

Nanoscale Advances ◽

10.1039/c9na00017h ◽

2019 ◽

Vol 1 (6) ◽

pp. 2365-2371 ◽

Cited By ~ 6

Author(s):

Hanif Haidari ◽

Nirmal Goswami ◽

Richard Bright ◽

Zlatko Kopecki ◽

Allison J. Cowin ◽

...

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Valence State ◽

Antibacterial Effect ◽

Resistant Bacteria ◽

Drug Resistant ◽

Drug Resistant Bacteria

The interplay between size and valence state in ∼3 nm silver nanoparticles resulted in the highest antibacterial effect against multi-drug resistant bacteria.

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Silver nanoparticles-decorated and mesoporous silica coated single-walled carbon nanotubes with an enhanced antibacterial activity for killing drug-resistant bacteria

Nano Research ◽

10.1007/s12274-020-2621-3 ◽

2020 ◽

Vol 13 (2) ◽

pp. 389-400 ◽

Cited By ~ 4

Author(s):

Yu Zhu ◽

Jia Xu ◽

Yanmao Wang ◽

Cang Chen ◽

Hongchen Gu ◽

...

Keyword(s):

Carbon Nanotubes ◽

Silver Nanoparticles ◽

Antibacterial Activity ◽

Mesoporous Silica ◽

Single Walled Carbon Nanotubes ◽

Resistant Bacteria ◽

Drug Resistant ◽

Single Walled Carbon ◽

Drug Resistant Bacteria ◽

Walled Carbon Nanotubes

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Novel Seleno- and Thio-Urea Containing Dihydropyrrol-2-One Analogues as Antibacterial Agents

Antibiotics ◽

10.3390/antibiotics10030321 ◽

2021 ◽

Vol 10 (3) ◽

pp. 321

Author(s):

Shekh Sabir ◽

Tsz Tin Yu ◽

Rajesh Kuppusamy ◽

Basmah Almohaywi ◽

George Iskander ◽

...

Keyword(s):

Antibacterial Activity ◽

Antibiotic Resistance ◽

Quorum Sensing ◽

Antibacterial Agents ◽

Inhibitory Concentration ◽

Resistant Bacteria ◽

Drug Resistant ◽

Positive Bacterium ◽

Quorum Sensing Inhibition ◽

Drug Resistant Bacteria

The quorum sensing (QS) system in multi-drug-resistant bacteria such as P. aeruginosa is primarily responsible for the development of antibiotic resistance and is considered an attractive target for antimicrobial drug discovery. In this study, we synthesised a series of novel selenourea and thiourea-containing dihydropyrrol-2-one (DHP) analogues as LasR antagonists. The selenium DHP derivatives displayed significantly better quorum-sensing inhibition (QSI) activities than the corresponding sulphur analogues. The most potent analogue 3e efficiently inhibited the las QS system by 81% at 125 µM and 53% at 31 µM. Additionally, all the compounds were screened for their minimum inhibitory concentration (MIC) against the Gram-positive bacterium S. aureus, and interestingly, only the selenium analogues showed antibacterial activity, with 3c and 3e being the most potent with a MIC of 15.6 µM.

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Synergistic Antibacterial Activity of Lantana camara L., Parthenium hysterophorus L., Cannabis sativa L. and Justicia adhatoda L. Leaves Extract against Procured Multi-drug Resistant Bacteria In Vitro

European Journal of Medicinal Plants ◽

10.9734/ejmp/2021/v32i330379 ◽

2021 ◽

pp. 34-40

Author(s):

Jyoti Chandola ◽

Pooja Singh ◽

Rishabh Garg ◽

Narotam Sharma

Keyword(s):

Antibacterial Activity ◽

Medicinal Plants ◽

Cannabis Sativa ◽

Lantana Camara ◽

Parthenium Hysterophorus ◽

Resistant Bacteria ◽

Drug Resistant ◽

Drug Resistant Bacteria ◽

Weed Plants ◽

Justicia Adhatoda

The scientific study of this research has been focused on synergistic antibacterial activity of two weed plants, Lantana camara L., Parthenium hysterophorus L. alongwith two medicinal plants, Cannabis sativa L., Justicia adhatoda L. against multi- drug resistant (MDR) bacteria. Dried leaf powders of the plants were extracted using air-dried method followed by the ethanol- solvent extraction method for the crude extract of the leaves. The crude extracts were tested for antibacterial activity against three MDR bacteria, that is, one Gram positive bacteria- Staphylococcus aureus and two Gram negative bacteria- Escherichia coli and Proteus mirabilis. Out of 18 antibiotics tested against procured bacteria, Staphylococcus aureus was resistant to 10 out of 10 tested antibiotics, Escherichia coli was resistant to 4 out of 12 tested antibiotics and Proteus mirabilis was resistant to 9 out of 10 tested antibiotics. The tested weed plants and the medicinal plants when combined together showed more zone of inhibition against multidrug resistant bacteria ( Two combinations of phytochemicals Lantana camara, Cannabis sativa and Lantana camara, Cannabis sativa, Justicia adhatoda, Parthenium hysterophorus showed maximum zones of inhibition, that is, 30 mm) as compared to when these plants were tested solitarily, showing pronounced antibacterial activity. These findings showed that the antibacterial activity enhanced when they were combined together and this potential could be used against various infectious diseases with more research and modification in this area. Weed plants also holds as much importance as the medicinal plants although not to that extent, but they clearly inhibit the growth of bacteria and this property of weeds along with the medicinal plants holds a promising future in treating many diseases caused by multi-drug resistant bacteria on the pharmaceutical level.

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Quorum Sensing Inhibition in Chromobacterium violaceum, Antibacterial Activity and GC-MS Analysis of Centaurea praecox (Oliv. & Hiern) Extracts

Letters in Applied NanoBioScience ◽

10.33263/lianbs94.15691577 ◽

2020 ◽

Vol 9 (4) ◽

pp. 1569-1577

Keyword(s):

Antibacterial Activity ◽

Quorum Sensing ◽

Research Strategy ◽

Chromobacterium Violaceum ◽

Resistant Bacteria ◽

Drug Resistant ◽

Control Drug ◽

Ms Analysis ◽

Drug Resistant Bacteria

The quorum sensing (QS) mechanism has become a viable research strategy for the discovery of plant-derived anti-virulent agents to control drug-resistant bacteria. The increasing incidences of drug-resistant bacteria and the effort to curb it necessitate this study. We investigated the QS inhibitory potential of Centaurea praecox extracts on Chromobacterium violaceum (CV), antibacterial activity, and determination of chemical composition using GC-MS. C. praecox was subjected to sequential extraction using hexane (HEX), dichloromethane (DCM), ethyl acetate (EA), ethanol (ET), and aqueous (AQ) solvents. The extracts were subsequently evaluated for antibacterial activity using disc diffusion and QS violacein inhibition using spectrophotometry. The antibacterial effects of the extracts were moderate on gram-positive bacteria at 4 mg/mL in the order: HEX >EA >DCM >ET =AQ. However, the DCM extract demonstrated the most effective violacein inhibition of ≥80% at 0.3 mg/mL. QS violacein inhibitions were generally found to be concentration-dependent in the order: DCM >EA >HEX >ET =AQ with efficacies of ≥ 90% inhibition at ≥ 0.6 mg/mL. GC-MS analysis on the most potent DCM extract revealed N-vinylmethanimine, N-ethyl formamide, and propanamide among components identified. We concluded that C. praecox DCM extract contains bioactive chemicals as QS inhibitors and potential anti-virulent agents capable of combating the pathogenicity of drug-resistant bacteria in vivo.

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Vacancy‐Induced Antibacterial Activity of XS 2– y Quantum Dots against Drug‐Resistant Bacteria for Treatment of Bacterial Keratitis

Small ◽

10.1002/smll.202004677 ◽

2020 ◽

Vol 16 (42) ◽

pp. 2004677

Author(s):

Huiyuan Li ◽

Xiao Wang ◽

Xiaofei Zhao ◽

Guanhua Li ◽

Fengyan Pei ◽

...

Keyword(s):

Quantum Dots ◽

Antibacterial Activity ◽

Resistant Bacteria ◽

Bacterial Keratitis ◽

Drug Resistant ◽

Drug Resistant Bacteria

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Recombinant HNP-1 Produced by Escherichia coli Triggers Bacterial Apoptosis and Exhibits Antibacterial Activity against Drug-Resistant Bacteria

Microbiology Spectrum ◽

10.1128/spectrum.00860-21 ◽

2022 ◽

Author(s):

Qi Xie ◽

Yin Wang ◽

Mengmeng Zhang ◽

Shujia Wu ◽

Wei Wei ◽

...

Keyword(s):

Escherichia Coli ◽

Antibacterial Activity ◽

Mass Production ◽

Recombinant Protein Expression ◽

Cost Effective ◽

Resistant Bacteria ◽

Drug Resistant ◽

Effective Solution ◽

Drug Resistant Bacteria ◽

Human Neutrophil Peptide

Human neutrophil peptide-1 (HNP-1) is a promising antibiotic candidate, but its clinical application has been hampered by the difficulty of mass production and an inadequate understanding of its bactericidal mechanisms. In this study, we demonstrated that recombinant protein expression combined with ultrafiltration may be a simple and cost-effective solution to HNP-1 production.

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