Fatty Acids as Antibiofilm and Antivirulence Agents.

https://doi.org/10.1016/j.surfin.2022.102349

Green synthesis of multifunctional ZnO/chitosan nanocomposite film using wild Mentha pulegium extract for packaging applications

Facile green synthesis of CuO- ZnO nanocomposites from Argyreia nervosa leaves extract for photocatalytic degradation of Rhodamine B dye

Groundwater pollution is mostly caused by overuse of fertilizers, pesticides, contemporary agricultural practices, anthropogenic activities, home waste disposal, and the rapid expansion of the chemical industry. Drinking tainted water on a regular basis can have detrimental consequences on human health as well on environment. Nanoparticles (NPs) based contaminants alleviation strategy found to be most efficient, cost-effective and reliable. In this study, ZnO NPs were synthesized via citrus limon leaves extract as a sustainable/cost-effective method. Diverse microscopic and spectroscopic studies confirmed the formation of spherical ZnO NPs with size range 15-25 nm. Reactive green-19 (RG-19) was degraded photocatalytically under direct solar irradiation (degradation efficiency ∼ 92%, rate constant 0.03 min -1, 80 min) in the presence of ZnO NPs. These ZnO NPs also demonstrated highly substantial antibacterial action against two pathogenic Gram-positive (Bacillus subtilis, zone of clearance: 8.6 mm) and Gram-negative (Escherichia coli, zone of clearance: 9.8 mm) bacteria. Thus, the present study demonstrates the effective/sustainable NPs based platform for water remediation. 

Sustainable synthesis of biogenic ZnO NPs for mitigation of emerging pollutants and pathogens.

There is a crucial necessity for the formulation of efficient antimicrobial agents owing to the increasing prevalence of hospital-acquired bacterial infections triggered by multidrug-resistant microbes that result in significant deaths and illnesses around the world. Hence, the current investigation examined the antibacterial proficiency of zinc oxide nanoparticles formulated utilizing the green route against bacterial strains that were resistant to multiple drugs. In addition, the synergistic antibacterial action of ZnO nanoparticles (ZnO NPs) combined with colistin was investigated against the tested microbial strains to determine the efficiency of the bioinspired ZnO nanoparticles in boosting the antibacterial proficiency of colistin antibiotic. Incidentally, the bioinspired ZnO nanoparticles were synthesized using water extract of Origanum majorana leaves and these nanomaterials were physicochemically characterized using different analytical techniques. The bioactivity of the synthesized nanomaterials against multidrug-resistant bacterial strains was appraised using the agar diffusion method. The biogenic ZnO NPs at a concentration of 100 μg/disk revealed a compelling antimicrobial efficacy against the tested strains, expressing the maximum antimicrobial action against Escherichia coli strain with clear zone diameter of 38.16 ± 0.18 mm. The remarkable antibacterial proficiency might be accredited to the tiny particle size of the bioformulated ZnO NPs of 12.467 ± 1.36 nm. The net charge of ZnO nanomaterials was −14.8 mV while XRD analysis confirmed their hexagonal wurtzite structure. Furthermore, the bioformulated ZnO NPs showed a promising synergistic potency with colistin demonstrating respective synergism proportions of 91.05, 79.07, 75.04, 75.25, 56.28 and 10.60% against E. coli, Klebsiella pneumoniae, Acinetobacter baumannii, Salmonella typhimurium, Enterobacter cloacae, and Pseudomonas aeruginosa, respectively. In conclusion, the water extract of O. majorana leaves mediated green formulation of zinc oxide nanoparticles with unique physicochemical characteristics and effective antibacterial proficiency against the examined drug-resistant bacterial strains. These nanomaterials could be used in the synthesis of effective antibacterial coatings to control hospital acquired infections caused by multidrug-resistant bacterial pathogens.

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Green Synthesis of Zinc Oxide Nanocrystals Utilizing Origanum majorana Leaf Extract and Their Synergistic Patterns with Colistin against Multidrug-Resistant Bacterial Strains

Nanoparticles (NPs) exhibit distinct features compared to traditional physico-chemical synthesis and they have many applications in a wide range of fields of life sciences such as surface coating agents, catalysts, food packaging, corrosion protection, environmental remediation, electronics, biomedical and antimicrobial. Green-synthesized metal NPs, mainly from plant sources, have gained a lot of attention due to their intrinsic characteristics like eco-friendliness, rapidity and cost-effectiveness. In this study, zinc oxide (ZnO) NPs have been synthesized employing an aqueous leaf extract of Pelargonium odoratissimum (L.) as a reducing agent; subsequently, the biosynthesized ZnO NPs were characterized by ultraviolet-visible spectroscopy (UV-Vis), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED). Moreover, aqueous plant leaf extract was subjected to both qualitative and quantitative analysis. Antioxidant activity of ZnO NPs was assessed by DPPH assay, with varying concentrations of ZnO NPs, which revealed scavenging activity with IC50 = 28.11 μg mL−1. Furthermore, the anti-bacterial efficacy of the green synthesized ZnO NPs against four foodborne pathogenic bacterial strains was examined using the disk diffusion assay, and Staphylococcus aureus (ATCC 8095), Pseudomonas aeruginosa (ATCC10662) and Escherichia coli (ATCC 25922) were found to be the most sensitive against biosynthesized ZnO NPs, whereas the least sensitivity was shown by Bacillus cereus (ATCC 13753). The anti-inflammatory effect was also evaluated for both ZnO NPs and the aqueous leaf extract of P. odoratissimum through the human red blood cells (HRBC) membrane stabilization method (MSM) in vitro models which includes hypotonicity-induced hemolysis. A maximum membrane stabilization of ZnO NPs was found to be 95.6% at a dose of 1000 μg mL−1 compared with the standard indomethacin. The results demonstrated that leaf extract of P. odoratissimum is suitable for synthesizing ZnO NPs, with antioxidant, antibacterial as well as superior anti-inflammatory activity by improving the membrane stability of lysosome cells, which have physiological properties similar to erythrocyte membrane cells and have no hemolytic activity. Overall, this study provides biosynthesized ZnO NPs that can be used as a safe alternative to synthetic substances as well as a potential candidate for antioxidants, antibacterial and anti-inflammatory uses in the biomedical and pharmaceutical industries.

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Green Synthesis and Characterization of ZnO Nanoparticles Using Pelargonium odoratissimum (L.) Aqueous Leaf Extract and Their Antioxidant, Antibacterial and Anti-inflammatory Activities

Background Drug combination is a new therapy to improve antibiotic deficiency treatment towards biofilm resistance. Objective This study was conducted to determine the potential effect of sodium oleate to inhibit established biofilms of two strains, methylotrophic bacteria Methylophilus quaylei in combination with ampicillin. Minimum inhibitory concentration (MIC) of ampicillin was determined and added in combination with sodium oleate and examined on planktonic and established biofilms of two strains M. quaylei were characterized by different properties of cell surface hydrophobicity. Methods The effect on biofilms was evaluated by the number of colony forming units (CFUs), crystal violet assay, light and scanning electron microscopy. Results The study demonstrates that sodium oleate has a promoting activity against planktonic growth of M. quaylei strains and has a slight inhibitory effect on biofilm. Addition of sodium oleate enhances the bactericidal effect of ampicillin against biofilm cells. Combination of ampicillin 0.1 mg/ml (MIC) and sodium oleate 0.03 mg/ml showed a remarkable destruction effect on established biofilms. Discussion Combination of ampicillin 0.1 mg/ml (MIC) and sodium oleate 0.03 mg/ml showed a remarkable destruction effect on established biofilms. Overall, results indicated that sodium oleate in combination with ampicillin enhances the inhibition of M. quaylei biofilms and this combination can be utilized for combating bacterial biofilm resistance. Conclusion Overall, results indicated that sodium oleate in combination with ampicillin enhances the inhibition of M. quaylei biofilms and this combination can be utilized for combating bacterial biofilm resistance.

Sodium Oleate Increases Ampicillin Sensitivity in Methylophilus quaylei Biofilms on Teflon and Polypropylene.

Objective: In this study, copper oxide nanoparticles are produced using the probiotic Saccharomyces boulardii in order to assess their biological activity. The biological method of producing nanoparticles is gaining popularity due to its benefits over chemical and physical ways of synthesis in terms of affordability and environmental friendliness. Methods: To biosynthesize CuO NPs, copper sulfate was introduced at a concentration to S. boulardii’s cell-free supernatant. Results: The color change of the reaction mixture from light to dark after 150 rpm incubation, as well as the color change and antibacterial behavior, were indicators of S. bularedii’s biosynthesis of CuO NPs. The characterization completed by UV-visible spectroscopy, Atomic force microscopy, Energy Dispersive Spectroscopy, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, and X-ray diffraction (AFM). The CuO NP absorption spectra in the reaction mixture’s UV-visible spectroscopy were (537.93 nm). The XRD showed that CuO NPs’ crystal size was (14.65 nm). The SEM was provided; the shape was uniform and spherical, and the average size (16.03 nm). EDS was used to analyze the presence of elemental CuO NPs. The CuO NPs’ three-dimensional structure was seen by the AFM, and their average diameter was (41.11 nm). The FTIR spectrum reveals a variety of functional groups that are present at various locations. Gram positive and gram negative bacteria that were isolated from diabetic foot infections were multidrug resistant (MDR), and biosynthesized CuO NPs demonstrated antibacterial action against these bacteria (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus mirabilis). In the form of biofilm using a microtiter plate and treated by nanoparticles, all of the examined bacterial isolates demonstrated their capacity to form biofilm. The harmful bacteria when treated with CuO NPs this capacity was inhibited and eradicated. The concentrations of CuO NPs (1 mg/ml, 0.5 mg/ml, 0.25 mg/ml, and 0.12 mg/ml) revealed their antioxidant activity in vitro by scavenging DPPH free radicals; the mixture of DPPH and biogenic CuO NPs at this concentration had the highest inhibition titer (72.44%).

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Biological effect of copper oxide nanoparticles synthesized by Saccharomyces boulardii against of multidrug resistant bacteria isolated from diabetic foot infections

Green approach for the synthesis of ZnO nanoparticles using Cymbopogon citratus aqueous leaf extract: characterization and evaluation of their biological activities

Objective: Saccharomyces boulardii, a probiotic, is used in the current study’s manufacture of zinc oxide nanoparticles with the aim of assessing their biological activity. Due to its advantages over the chemical and physical techniques of synthesis in terms of affordability and environmental friendliness, the biological way of creating nanoparticles is becoming increasingly relevant. Methods: Zinc acetate was added at a dose necessary to biosynthesize ZnO NPs from S. boulardii’s cellfree supernatant (1 mM). Results: An evidence that S. bularedii was responsible for the reaction mixture’s color change from light to dark after 150 rpm of incubation was the color change and antibacterial behavior. Atomic force microscopy, scanning electron microscopy, energy dispersive spectroscopy, ultraviolet-visible spectroscopy, and X-ray diffraction (XRD) all contributed to the completion of the characterisation (AFM). The spectra of the ZnO NPs produced in the reaction mixture using UV-visible spectroscopy were (343.75 nm). The XRD showed that ZnO NPs’ crystal size was (13.31 nm). The SEM was provided; the shape was uniform and spherical, and the average size (24.61 nm). EDS was used to analyze the presence of elemental ZnO NPs. ZnO NPs’ three-dimensional structure was seen using AFM, and their average diameter was (62.89 nm). The FTIR spectrum reveals a variety of functional groups that are present at various locations. Gram positive and gram negative bacteria that were isolated from diabetic foot infections were multidrug resistant (MDR), and biosynthesized ZnO NPs demonstrated antibacterial action against these bacteria. (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus mirabilis). All of the studied bacterial isolates showed the ability to produce biofilms in the form of nanoparticle-treated biofilms on microtiter plates. When pathogenic bacteria were treated with ZnO NPs, this ability was stopped and eliminated. The ZnO NPs (1 mg/ml, 0.5 mg/ml, 0.25 mg/ml, and 0.12 mg/ml) demonstrated their antioxidant ability in vitro by scavenging DPPH free radicals. The combination of DPPH and biogenic ZnONPs at concentration 1 mg/ml showed the highest inhibitory titer (73.79%).

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Abir M H A Mohamed

Papers

Green Synthesis and Characterization of ZnO Nanoparticles Using Pelargonium odoratissimum (L.) Aqueous Leaf Extract and Their Antioxidant, Antibacterial and Anti-inflammatory Activities

Sodium Oleate Increases Ampicillin Sensitivity in Methylophilus quaylei Biofilms on Teflon and Polypropylene.

Biological effect of copper oxide nanoparticles synthesized by Saccharomyces boulardii against of multidrug resistant bacteria isolated from diabetic foot infections

Green approach for the synthesis of ZnO nanoparticles using Cymbopogon citratus aqueous leaf extract: characterization and evaluation of their biological activities

Biosynthesis of zinc oxide nanoparticles using saccharomyces boulardii and study their biological activities