Green Strategy–Based Synthesis of Silver Nanoparticles for Antibacterial Applications

Antibiotics have been the nucleus of chemotherapy since their discovery and introduction into the healthcare system in the 1940s. They are routinely used to treat bacterial infections and to prevent infections in patients with compromised immune systems and enhancing growth in livestock. However, resistance to last-resort antibiotics used in the treatment of multidrug-resistant infections has been reported worldwide. Therefore, this study aimed to evaluate green synthesized nanomaterials such as silver nanoparticles (AgNPs) as alternatives to antibiotics. UV-vis spectroscopy surface plasmon resonance peaks for AgNPs were obtained between 417 and 475 nm. An X-ray diffraction analysis generated four peaks for both Prunus africana extract (PAE) and Camellia sinensis extract (CSE) biosynthesized AgNPs positioned at 2θ angles of 38.2°, 44.4°, 64.5°, and 77.4° corresponding to crystal planes (111), (200), (220), and (311), respectively. A dynamic light-scattering analysis registered the mean zeta potential of +6.3 mV and +0.9 mV for PAE and CSE biosynthesized nanoparticles, respectively. Fourier transform infrared spectroscopy spectra exhibited bands corresponding to different organic functional groups confirming the capping of AgNPs by PAE and CSE phytochemicals. Field emission scanning electron microscopy imaging showed that AgNPs were spherical with average size distribution ranging from 10 to 19 nm. Biosynthesized AgNPs exhibited maximum growth inhibitory zones of 21 mm with minimum inhibitory concentration and minimum bactericidal concentration of 125 and 250 μg/ml, respectively, against carbapenem-resistant bacteria.

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Physiochemical properties and antibacterial activity of silver nanoparticles green synthesized by Camellia sinensis and Prunus africana extracts

10.21203/rs.3.rs-143995/v1 ◽

2021 ◽

Author(s):

Kenneth Ssekatawa ◽

Denis Byarugaba ◽

Charles Kato ◽

Eddie Wampande ◽

Francis Ejobi ◽

...

Keyword(s):

Bacterial Infections ◽

Maximum Growth ◽

Xrd Analysis ◽

Resistant Bacteria ◽

Prunus Africana ◽

Carbapenem Resistant ◽

Growth Inhibitory ◽

Vis Spectroscopy ◽

Biosynthesized Agnps ◽

Average Size

Abstract Antibiotics have been the nucleus of chemotherapy since their discovery and introduction into the healthcare system in the 1940s. They are used routinely not only to treat bacterial infections but also to prevent infections in patients with compromised immune systems and enhancing growth in livestock. However, resistance to last-resort antibiotics used in the treatment of MDR infections has been reported worldwide. Therefore, the aim of this study was to evaluate green synthesized nanomaterials such as AgNPs as alternatives to antibiotics. UV Vis Spectroscopy surface plasmon resonance peaks for AgNPs were obtained between 417 to 475nm. XRD analysis generated 4 peaks for both PAE and CSE biosynthesized AgNPs positioned at 2θ angles of 38.2˚, 44.4˚, 64.5˚, and 77.4˚ corresponding to crystal planes (111), (200), (220) and (311) respectively. DLS registered mean zeta potential of + 6.3mV and + 0.9mV for PAE and CSE biosynthesized nanoparticles respectively. FTIR spectra exhibited bands corresponding to different organic functional groups confirming capping of AgNPs by PAE and CSE phytochemicals. FESEM imaging showed that AgNPs were spherical with average size distribution ranging from 10 to 19nm. Biosynthesized AgNPs exhibited maximum growth inhibitory zones of 21mm with MIC and MBC of 125µg/ml and 250µg/ml respectively against carbapenem resistant bacteria.

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Ampicillin-augmented silver nanoparticles for synergistic antimicrobial response: A promising therapeutic approach

Current Pharmaceutical Biotechnology ◽

10.2174/1389201022666210119101522 ◽

2021 ◽

Vol 22 ◽

Author(s):

Kashan Khan ◽

Mohd Aamir Qureshi ◽

Ameer Azam ◽

Moinuddin ◽

Javed Musarrat ◽

...

Keyword(s):

Antimicrobial Activity ◽

Silver Nanoparticles ◽

Zeta Potential ◽

Bacterial Infections ◽

Colloidal Stability ◽

Resistant Bacteria ◽

Antimicrobial Drugs ◽

Vis Spectroscopy ◽

Microbial Infections ◽

Ft Ir

Aims: Globally Scientists are working to find more efficient antimicrobial drugs to treat microbial infections and kill drug-resistant bacteria. Background: Despite the availability of numerous antimicrobial drugs bacterial infections still poses a serious threat to global health. Due to a constant decline in the effectiveness of antibiotics owing to their repeated exposure as well as shortlasting antimicrobial activity, led to the demand for developing novel therapeutic agents capable of controlling microbial infections. Objective: In this study, we report antimicrobial activity of chemically synthesized silver nanoparticles (cAgNPs) augmented with ampicillin (amp) in order to increase antimicrobial response against Escherichia coli (gram –ve), Staphylococcus aureus (gram +ve) and Streptococcus mutans (gram +ve). Methods: Nanostructure, colloidal stability, morphology and size of cAgNPs before and after functionalization were explored by UV-vis spectroscopy, FT-IR, zeta potential and TEM. The formation and functionalization of cAgNPs was confirmed from UV-vis spectroscopy and FT-IR patterns. From TEM the average sizes of cAgNPs and cAgNP-amp were found to be 13 and 7.8 nm respectively, and change in colloidal stability after augmentation was confirmed from zeta potential values. The antimicrobial efficacies of cAgNP-amp and cAgNPs against E. coli S. aureus and S. mutans were studied by determining minimum inhibitory concentrations (MICs), zone of inhibition, assessment of viable and non-viable bacterial cells and quantitative assessment of biofilm. Results & Discussion: Our results revealed cAgNP-amp to be highly bactericidal compared to cAgNPs or amp alone. The nano-toxicity studies indicated cAgNP-amp to be less toxic compared to cAgNPs alone. Results: This study manifested that cAgNPs show synergistic antimicrobial effect when they get functionalized with amp suggesting their application in curing long-term bacterial infections.

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Biogenic Nanosilver against Multidrug-Resistant Bacteria (MDRB)

Antibiotics ◽

10.3390/antibiotics7030069 ◽

2018 ◽

Vol 7 (3) ◽

pp. 69 ◽

Cited By ~ 28

Author(s):

Caio Barros ◽

Stephanie Fulaz ◽

Danijela Stanisic ◽

Ljubica Tasic

Keyword(s):

Health Care ◽

Silver Nanoparticles ◽

Bacterial Infections ◽

Health Care Systems ◽

Antibiotic Use ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

New Paradigm ◽

Multidrug Resistant Bacteria ◽

Care Systems

Multidrug-resistant bacteria (MDRB) are extremely dangerous and bring a serious threat to health care systems as they can survive an attack from almost any drug. The bacteria’s adaptive way of living with the use of antimicrobials and antibiotics caused them to modify and prevail in hostile conditions by creating resistance to known antibiotics or their combinations. The emergence of nanomaterials as new antimicrobials introduces a new paradigm for antibiotic use in various fields. For example, silver nanoparticles (AgNPs) are the oldest nanomaterial used for bactericide and bacteriostatic purposes. However, for just a few decades these have been produced in a biogenic or bio-based fashion. This review brings the latest reports on biogenic AgNPs in the combat against MDRB. Some antimicrobial mechanisms and possible silver resistance traits acquired by bacteria are also presented. Hopefully, novel AgNPs-containing products might be designed against MDR bacterial infections.

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Biosynthesis of Silver Nanoparticles Using Ligustrum Ovalifolium Fruits and Their Cytotoxic Effects

Nanomaterials ◽

10.3390/nano8080627 ◽

2018 ◽

Vol 8 (8) ◽

pp. 627 ◽

Cited By ~ 13

Author(s):

Bianca Moldovan ◽

Vladislav Sincari ◽

Maria Perde-Schrepler ◽

Luminita David

Keyword(s):

Silver Nanoparticles ◽

Synthesis Method ◽

Cost Effective ◽

Bioactive Molecules ◽

Energetic Cost ◽

Fruit Extract ◽

Vis Spectroscopy ◽

Biosynthesized Agnps ◽

Average Size

The present study reports for the first time the efficacy of bioactive compounds from Ligustrum ovalifolium L. fruit extract as reducing and capping agents of silver nanoparticles (AgNPs), developing a green, zero energetic, cost effective and simple synthesis method of AgNPs. The obtained nanoparticles were characterized by UV-Vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR), confirming that nanoparticles were crystalline in nature, spherical in shape, with an average size of 7 nm. The FTIR spectroscopy analysis demonstrated that the AgNPs were capped and stabilized by bioactive molecules from the fruit extract. The cytotoxicity of the biosynthesized AgNPs was in vitro evaluated against ovarian carcinoma cells and there were found to be effective at low concentration levels.

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Anti-Bacterial and Anti-Candidal Activity of Silver Nanoparticles Biosynthesized Using Citrobacter spp. MS5 Culture Supernatant

Biomolecules ◽

10.3390/biom10060944 ◽

2020 ◽

Vol 10 (6) ◽

pp. 944

Author(s):

Aftab Hossain Mondal ◽

Dhananjay Yadav ◽

Asghar Ali ◽

Neelofar Khan ◽

Jun O Jin ◽

...

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Antifungal Activity ◽

Culture Supernatant ◽

Bacterial Isolate ◽

Multidrug Resistant ◽

Candida Spp ◽

X Ray ◽

Vis Spectroscopy ◽

Biosynthesized Agnps

The present study described the extracellular synthesis of silver nanoparticles (AgNPs) using environmental bacterial isolate Citrobacter spp. MS5 culture supernatant. To our best knowledge, no previous study reported the biosynthesis of AgNPs using this bacterial isolate. The biosynthesized AgNPs were characterized using different techniques like UV-Vis spectroscopy, fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) equipped with energy dispersive X-ray (EDX). The analysis of UV-Vis spectra revealed absorption maxima at 415 nm due to surface plasmon resonance (SPR) indicated the formation of AgNPs and FTIR spectrum confirmed the participation of proteins molecule in AgNPs synthesis. XRD and EDX spectrum confirmed the metallic and crystalline nature of AgNPs. TEM and SEM showed spherical nanoparticles with a size range of 5–15 nm. The biosynthesized AgNPs showed effective independent as well as enhanced combined antibacterial activity against extended spectrum β-lactamase (ESBL) producing multidrug resistant Gram-negative bacteria. Further, effective antifungal activity of AgNPs was observed towards pathogenic Candida spp. The present study provides evidence for eco-friendly biosynthesis of well-characterized AgNPs and their potential antibacterial as well as antifungal activity.

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Characterization and Pharmacological Efficacy of Silver Nanoparticles Biosynthesized Using the Bark Extract of Garcinia Kola

Journal of Chemistry ◽

10.1155/2020/2876019 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Sunday Adewale Akintelu ◽

Seyifunmi Charles Olugbeko ◽

Femi Adekunle Folorunso ◽

Abel Kolawole Oyebamiji ◽

Aderonke Similoluwa Folorunso

Keyword(s):

Silver Nanoparticles ◽

Bacterial Infections ◽

Diffusion Method ◽

Bark Extract ◽

Tem Analysis ◽

Garcinia Kola ◽

Antibacterial Screening ◽

Biosynthesized Agnps ◽

Average Size ◽

Promising Source

The delinquent peril of bacterial infections affecting human kind is becoming unbearable. This study was embarked on to investigate the antimicrobial activity of biosynthesized silver nanoparticles (AgNPs) using Garcinia kola bark extract against some bacteria strains. Fresh barks of Garcinia kola were obtained from the “Gbeleju” farm land in Irele town in Ondo state region of Nigeria. Exactly 0.4 g of previously pulverized bark of Garcinia kola was immersed into 20 mL of distilled water and heated at 60–70°C for 10 minutes yielding the extract. The biosynthesized nanoparticle was characterized with UV spectroscope, Fourier infrared spectroscope (FTIR), transmission electron microscope (TEM), and energy dispersive X-Ray analyzer (EDX). Then, 0.2 g of the silver nanoparticles was dissolved in 2 ml of water to yield 100 mg/ml of the stock solution which was further diluted for the antibacterial analysis via the disc diffusion method. The result obtained from the analytical characterization of the biosynthesized silver nanoparticles revealed a spherical particle shape, particle size in the range of 12.23 to 27.90 nm with an average size of 20.07 nm via TEM analysis. The FTIR analysis confirmed the presence of -OH functional group for the stabilization of the silver nanoparticles formed due to the broad peak at wavelength 3324.52 and 3344.21 cm−1. The EDX analysis revealed carbon, nitrogen, oxygen, aluminum, potassium, copper, and silver as the elements present in the nanoparticles. Results obtained from the antibacterial screening of the biosynthesized AgNPs showed inhibitory potential that are capable of obstructing the growth of the test bacteria. This investigation ascertained the biosynthesized AgNPs as a remedy for curing bacterial infections and also a promising source for novel antibacterial agent.

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Green Synthesis of Silver Nanoparticles and Evaluation of Their Antibacterial Activity against Multidrug-Resistant Bacteria and Wound Healing Efficacy Using a Murine Model

Antibiotics ◽

10.3390/antibiotics9120902 ◽

2020 ◽

Vol 9 (12) ◽

pp. 902

Author(s):

Vajravathi Lakkim ◽

Madhava C. Reddy ◽

Roja Rani Pallavali ◽

Kakarla Raghava Reddy ◽

Ch Venkata Reddy ◽

...

Keyword(s):

Electron Microscopy ◽

Wound Healing ◽

Silver Nanoparticles ◽

Multidrug Resistant ◽

Biomedical Science ◽

Resistant Bacteria ◽

Zone Of Inhibition ◽

Ag Nps ◽

Bacteriolytic Activity ◽

Vis Spectroscopy

Green nanotechnology has significant applications in various biomedical science fields. In this study, green-synthesized silver nanoparticles, prepared by using Catharanthus roseus and Azadirachta indica extracts, were characterized using UV–Vis spectroscopy, dynamic light scattering, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Silver nanoparticles (Ag NPs) synthesized from leaf extracts of C. roseus and A. indica effectively inhibited the growth of multidrug-resistant (MDR) bacteria isolated from patients with septic wound infections. The maximum bacteriolytic activity of the green-synthesized Ag NPs of C. roseus and A. indica against the MDR bacterium K. Pneumoniae was shown by a zone of inhibition of 19 and 16 mm, respectively. C. roseus Ag NPs exhibited more bacteriolytic activity than A. indica Ag NPs in terms of the zone of inhibition. Moreover, these particles were effective in healing wounds in BALB/c mice. Ag NPs of C. roseus and A. indica enhanced wound healing by 94% ± 1% and 87% ± 1%, respectively. Our data suggest that Ag NPs from C. roseus and A. indicia ameliorate excision wounds, and wound healing could be due to their effective antimicrobial activity against MDR bacteria. Hence, these Ag NPs could be potential therapeutic agents for the treatment of wounds.

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Antibacterial Effect of Silver Nanoparticles Synthesized Using Murraya koenigii (L.) against Multidrug-Resistant Pathogens

Bioinorganic Chemistry and Applications ◽

10.1155/2019/4649506 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 33

Author(s):

Faizan Abul Qais ◽

Anam Shafiq ◽

Haris M. Khan ◽

Fohad M. Husain ◽

Rais A. Khan ◽

...

Keyword(s):

Silver Nanoparticles ◽

Bacterial Infections ◽

Enteric Bacteria ◽

Multidrug Resistant ◽

Murraya Koenigii ◽

E Coli ◽

Vis Spectroscopy ◽

Zones Of Inhibition

Development of multidrug resistance among pathogens has become a global problem for chemotherapy of bacterial infections. Extended-spectrum β-lactamase- (ESβL-) producing enteric bacteria and methicillin-resistant Staphylococcus aureus (MRSA) are the two major groups of problematic MDR bacteria that have evolved rapidly in the recent past. In this study, the aqueous extract of Murraya koenigii leaves was used for synthesis of silver nanoparticles. The synthesized MK-AgNPs were characterized using UV-vis spectroscopy, FTIR, XRD, SEM, and TEM, and their antibacterial potential was evaluated on multiple ESβL-producing enteric bacteria and MRSA. The nanoparticles were predominantly found to be spheroidal with particle size distribution in the range of 5–20 nm. There was 60.86% silver content in MK-AgNPs. Evaluation of antibacterial activity by the disc-diffusion assay revealed that MK-AgNPs effectively inhibited the growth of test pathogens with varying sized zones of inhibition. The MICs of MK-AgNPs against both MRSA and methicillin-sensitive S. aureus (MSSA) strains were 32 μg/ml, while for ESβL-producing E. coli, it ranged from 32 to 64 μg/ml. The control strain of E. coli (ECS) was relatively more sensitive with an MIC of 16 μg/ml. The MBCs were in accordance with the respective MICs. Analysis of growth kinetics revealed that the growth of all tested S. aureus strains was inhibited (∼90%) in presence of 32 μg/ml of MK-AgNPs. The sensitive strain of E. coli (ECS) showed least resistance to MK-AgNPs with >81% inhibition at 16 μg/ml. The present investigation revealed an encouraging result on in vitro efficacy of green synthesized MK-AgNPs and needed further in vivo assessment for its therapeutic efficacy against MDR bacteria.

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Antibiotic-Resistant Bacteria in Clams—A Study on Mussels in the River Rhine

Antibiotics ◽

10.3390/antibiotics10050571 ◽

2021 ◽

Vol 10 (5) ◽

pp. 571

Author(s):

Nicole Zacharias ◽

Iris Löckener ◽

Sarah M. Essert ◽

Esther Sib ◽

Gabriele Bierbaum ◽

...

Keyword(s):

Bacterial Infections ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

River Rhine ◽

Antibiotic Resistant Bacteria ◽

Surrounding Water ◽

Antibiotic Resistant

Bacterial infections have been treated effectively by antibiotics since the discovery of penicillin in 1928. A worldwide increase in the use of antibiotics led to the emergence of antibiotic resistant strains in almost all bacterial pathogens, which complicates the treatment of infectious diseases. Antibiotic-resistant bacteria play an important role in increasing the risk associated with the usage of surface waters (e.g., irrigation, recreation) and the spread of the resistance genes. Many studies show that important pathogenic antibiotic-resistant bacteria can enter the environment by the discharge of sewage treatment plants and combined sewage overflow events. Mussels have successfully been used as bio-indicators of heavy metals, chemicals and parasites; they may also be efficient bio-indicators for viruses and bacteria. In this study an influence of the discharge of a sewage treatment plant could be shown in regard to the presence of E. coli in higher concentrations in the mussels downstream the treatment plant. Antibiotic-resistant bacteria, resistant against one or two classes of antibiotics and relevance for human health could be detected in the mussels at different sampling sites of the river Rhine. No multidrug-resistant bacteria could be isolated from the mussels, although they were found in samples of the surrounding water body.

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Liposomes as Antibiotic Delivery Systems: A Promising Nanotechnological Strategy against Antimicrobial Resistance

Molecules ◽

10.3390/molecules26072047 ◽

2021 ◽

Vol 26 (7) ◽

pp. 2047

Author(s):

Magda Ferreira ◽

Maria Ogren ◽

Joana N. R. Dias ◽

Marta Silva ◽

Solange Gil ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Bacterial Infections ◽

Private Investment ◽

Therapeutic Index ◽

Multidrug Resistant ◽

Current Treatment ◽

Delivery Systems ◽

Resistant Bacteria ◽

Bacterial Cells ◽

Antimicrobial Drugs

Antimicrobial drugs are key tools to prevent and treat bacterial infections. Despite the early success of antibiotics, the current treatment of bacterial infections faces serious challenges due to the emergence and spread of resistant bacteria. Moreover, the decline of research and private investment in new antibiotics further aggravates this antibiotic crisis era. Overcoming the complexity of antimicrobial resistance must go beyond the search of new classes of antibiotics and include the development of alternative solutions. The evolution of nanomedicine has allowed the design of new drug delivery systems with improved therapeutic index for the incorporated compounds. One of the most promising strategies is their association to lipid-based delivery (nano)systems. A drug’s encapsulation in liposomes has been demonstrated to increase its accumulation at the infection site, minimizing drug toxicity and protecting the antibiotic from peripheral degradation. In addition, liposomes may be designed to fuse with bacterial cells, holding the potential to overcome antimicrobial resistance and biofilm formation and constituting a promising solution for the treatment of potential fatal multidrug-resistant bacterial infections, such as methicillin resistant Staphylococcus aureus. In this review, we aim to address the applicability of antibiotic encapsulated liposomes as an effective therapeutic strategy for bacterial infections.

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