Phytoremediation of dyes using Lagerstroemia speciosa mediated silver nanoparticles and its biofilm activity against clinical strains Pseudomonas aeruginosa

Prunus persica leaves aqueous extract mediated biosynthesis of Ag nanoparticles and assessment of its anti-quorum sensing potential against Hafnia species

Hafnia sp. was one of the specific spoilage bacteria in aquatic products, and the aim of the study was to investigate the inhibition ability of the silver nanoparticles (AgNPs) biosynthesis by an aqueous extract of Prunus persica leaves toward the spoilage-related virulence factors of Hafnia sp. The synthesized P-AgNPs were spherical, with a mean particle size of 36.3 nm and zeta potential of 21.8 ± 1.33 mV. In addition, the inhibition effects of P-AgNPs on the growth of two Hafnia sp. strains and their quorum sensing regulated virulence factors, such as the formation of biofilm, secretion of N-acetyl-homoserine lactone (AHLs), proteases, and exopolysaccharides, as well as their swarming and swimming motilities were evaluated. P-AgNPs had a minimum inhibitory concentration (MIC) of 64 μg ml-1 against the two Hafnia sp. strains. When the concentration of P-AgNPs was below MIC, it could inhibit the formation of biofilms by Hafnia sp at 8-32 μg ml-1, but it promoted the formation of biofilms by Hafnia sp at 0.5-4 μg ml-1. P-AgNPs exhibited diverse inhibiting effects on AHLs and protease production, swimming, and swarming motilities at various concentrations.

Silver nanoparticle ecotoxicity and phytoremediation: a critical review of current research and future prospects

Silver nanoparticles (AgNPs) are widely used in various industries, including textiles, electronics, and biomedical fields, due to their unique optical, electronic, and antimicrobial properties. However, the extensive use of AgNPs has raised concerns about their potential ecotoxicity and adverse effects on the environment. AgNPs can enter the environment through different pathways, such as wastewater, surface runoff, and soil application and can interact with living organisms through adsorption, ingestion, and accumulation, causing toxicity and harm. The small size, high surface area-to-volume ratio, and ability to generate reactive oxygen species (ROS) make AgNPs particularly toxic. Various bioremediation strategies, such as phytoremediation, have been proposed to mitigate the toxic effects of AgNPs and minimize their impact on the environment. Further research is needed to improve these strategies and ensure their safety and efficacy in different environmental settings.

Natural waste-derived nano photocatalysts for azo dye degradation

Due to their widespread application in water purification, there is a significant interest in synthesising nanoscale photocatalysts. Nanophotocatalysts are primarily manufactured through chemical methods, which can lead to side effects like pollution, high-energy usage, and even health issues. To address these issues, "green synthesis" was developed, which involves using plant extracts as reductants or capping agents rather than industrial chemical agents. Green fabrication has the benefits of costs less, pollution reduction, environmental protection and human health safety, compared to the traditional methods. This article summarises recent advances in the environmentally friendly synthesis of various nanophotocatalysts employed in the degradation of azo dyes. This study compiles critical findings on natural and artificial methods to achieve the goal. Green synthesis is constrained by the time and place of production and issues with low purity and poor yield, reflecting the complexity of plants' geographical and seasonal distributions and their compositions. However, green photocatalyst synthesis provides additional growth opportunities and potential uses.

Efficient One-Pot Solvothermal Synthesis and Characterization of Zirconia Nanoparticle-Decorated Reduced Graphene Oxide Nanocomposites: Evaluation of Their Enhanced Anticancer Activity toward Human Cancer Cell Lines

This study mainly deals with an effective one-pot solvothermal synthetic pathway for the preparation of uniformly dispersed zirconium oxide nanoparticles on the flattened rough surface of reduced graphene oxide (ZrO₂/rGO NCs) using the aqueous leaf extract of Andrographis paniculata. After obtaining detailed information on the preparation and characterization, the anticancer activity of the synthesized ZrO₂/rGO nanocrystals (NCs) was evaluated on two human cancer cell lines (A549 and HCT116) along with one normal human cell line (hMSC). The 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide assays revealed that ZrO₂/rGO NCs exhibited a dose-dependent cytotoxicity pattern. The cell viability (%) drastically decreases up to 96-98% after exposure to an optimal concentration of 10 ppm nanocomposites. Analysis of both the reactive oxygen species generation and the Annexin V-FTIC staining assays reveal that ZrO₂/rGO NCs have the ability to induce apoptosis in A549 and HCT116 cell lines. Thus, the green synthesis of ZrO₂/rGO NCs shows potential in developing efficient therapeutic agents for cancer therapy.

Microscopic visualization of the antibiofilm potential of essential oils against Staphylococcus aureus and Klebsiella pneumoniae

Biofilms are known to pose great risks in clinical settings, drinking water systems, and food industries as they show considerable resistance to various environmental stresses. This study investigates the antibiofilm potential of different essential oils against the test organisms Staphylococcus aureus (ATCC 25923) and Klebsiella pneumoniae (ATCC 13883). Moreover, different stages of biofilm formation were also assessed using light microscopic assays. For determining the antibiofilm activity, a total of five essential oils namely cinnamon (Cinnamomum Verum), tea tree (Melaleuca alternifolia), lavender (Lavandula), peppermint (Mentha piperita), and lemongrass (Cymbopogon citratus) were tested for their ability to inhibit the initial attachment of microbial cells as well as the eradication of mature biofilm using the microtitre plate assay. For both the test strains (S. aureus and K. pneumoniae) the concentration of 30 μl/100 μl of cinnamon oil exhibited the highest antibiofilm activity followed by the activity of peppermint oil at the same concentration. These results were further validated by employing the light microscopy assay for observing the antibiofilm potential of cinnamon and peppermint essential oils.

Silver Nanoparticle's Toxicological Effects and Phytoremediation

The advancement in nanotechnology has brought numerous benefits for humans in diverse areas including industry, medicine, and agriculture. The demand in the application of nanomaterials can result in the release of these anthropogenic materials into soil and water that can potentially harm the environment by affecting water and soil properties (e.g., soil texture, pH, organic matter, and water content), plants, animals, and subsequently human health. The properties of nanoparticles including their size, surface area, and reactivity affect their fate in the environment and can potentially result in their toxicological effects in the ecosystem and on living organisms. There is extensive research on the application of nano-based materials and the consequences of their release into the environment. However, there is little information about environmentally friendly approaches for removing nanomaterials from the environment. This article provides insight into the application of silver nanoparticles (AgNPs), as one of the most commonly used nanomaterials, their toxicological effects, their impacts on plants and microorganisms, and briefly reviews the possibility of remediation of these metabolites using phytotechnology approaches. This article provides invaluable information to better understand the fate of nanomaterials in the environment and strategies in removing them from the environment.

Application potential of biogenically synthesized silver nanoparticles using Lythrum salicaria L. extracts as pharmaceuticals and catalysts for organic pollutant degradation

This study was designed to evaluate the optimal conditions for the eco-friendly synthesis of silver nanoparticles (AgNPs) using Lythrum salicaria L. (Lythraceae) aqueous extracts and their potential application and safe use. AgNPs synthesized using L. salicaria aerial parts (LSA-AgNPs) and root extract (LSR-AgNPs) were characterized by UV-Vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM/EDS), and X-ray powder diffraction (XRPD). Dynamic light scattering (DLS) was used for the determination of the size distribution profiles of the obtained nanoparticles. Both L. salicaria extracts showed high phenolic content, while the flavone C-glucosides orientin, vitexin, and isovitexin were detected in extracts using HPLC. The synthesized AgNPs displayed growth inhibition of the tested bacteria and fungi in concentrations between 0.156 and 1.25 mg mL⁻¹. The studied nanoparticles also showed antioxidant potential and gained selectivity at different concentrations on different cancer cell lines. Concentrations of LSA-AgNPs were found to be 20.5 and 12 μg mL⁻¹ towards A431 and SVT2, respectively, while LSR-AgNPs were effective only against A431 cancer cells (62 μg mL⁻¹). The hemolytic activity of LSA-AgNPs in concentrations up to 150 μg mL⁻¹ was not observed, while LSR-AgNPs in the highest applied concentration hemolyzed 2.8% of erythrocytes. The degradation possibility of Congo red and 4-nitrophenol using LSA-AgNPs and LSR-AgNPs as catalysts was also proven. The results indicate that L. salicaria may be used for the eco-friendly synthesis of AgNPs with possible applications as antimicrobial and selective cytotoxic agents towards cancer cell lines, as well as in catalytic degradation of pollutants.

This study was designed to evaluate the optimal conditions for the eco-friendly synthesis of silver nanoparticles (AgNPs) using Lythrum salicaria L. (Lythraceae) aqueous extracts and their potential application and safe use.

Antibacterial and antibiofilm potential of silver nanoparticles against antibiotic-sensitive and multidrug-resistant Pseudomonas aeruginosa strains

Due to the severity of infections caused by P. aeruginosa and the limitations in treatment, it is necessary to find new therapeutic alternatives. Thus, the use of silver nanoparticles (AgNPs) is a viable alternative because of their potential actions in the combat of microorganisms, showing efficacy against Gram-positive and Gram-negative bacteria, including multidrug-resistant microorganisms (MDR). In this sense, the aim of this work was to conduct a literature review related to the antibacterial and antibiofilm activity of AgNPs against antibiotic-sensitive and multidrug-resistant Pseudomonas aeruginosa strains. The AgNPs are promising for future applications, which may match the clinical need for effective antibiotic therapy. The size of AgNPs is a crucial element to determine the therapeutic activity of nanoparticles, since smaller particles present a larger surface area of contact with the microorganism, affecting their vital functioning. AgNPs adhere to the cytoplasmic membrane and cell wall of microorganisms, causing disruption, penetrating the cell, interacting with cellular structures and biomolecules, and inducing the generation of reactive oxygen species and free radicals. Studies describe the antimicrobial activity of AgNPs at minimum inhibitory concentration (MIC) between 1 and 200 μg/mL against susceptible and MDR P. aeruginosa strains. These studies have also shown antibiofilm activity through disruption of biofilm structure, and oxidative stress, inhibiting biofilm growth at concentrations between 1 and 600 μg/mL of AgNPs. This study evidences the advance of AgNPs as an antibacterial and antibiofilm agent against Pseudomonas aeruginosa strains, demonstrating to be an extremely promising approach to the development of new antimicrobial systems.

Biomimetic detoxifier Prunus cerasifera Ehrh. silver nanoparticles: innate green bullets for morbific pathogens and persistent pollutants

Silver nanoparticles were fabricated in the presence and absence of light with silver nitrate and aqueous extract of Prunus cerasifera leaf via facile and one-pot green method. P. cerasifera leaf extract reduced and stabilized the nanoparticles with phytometabolites expunging the need for addition of external reducing agents. Optimized silver nanoparticle syntheses was done with variations in leaf extract concentration, time, temperature, and molarity for deciphering the photocatalytic, antifungal, and antibacterial potential of synthesized nanoparticles. Optical, compositional, and morphological analyses of the synthesized nanoparticles were done by UV-visible spectrometry (UV-Vis), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Formation of silver nanoparticles was confirmed firstly through UV-Vis by exhibition of peaks with 400-450 nm. FTIR confirmed the presence of major organic groups responsible for reduction of nanoparticles. AFM confirmed the spherical morphology of the synthesized nanoparticles with remarkable dispersion without any agglomeration. Phytochemical analysis for P. cerasifera leaf metabolites was done by GC-MS. Spherical nanoparticles having a size range of 57-144 nm were obtained with face-centered cubic crystals. The average crystallite size obtained from XRD spectra was 2.34 nm. Enhanced photocatalytic first-order kinetics were obtained for persistent organic pollutants, i.e., crystal violet, methylene blue, and malachite green (R² = 0.99, 0.99, 0.98) in less than 15 min. Biomedical and agricultural significance as an antibiotic drug and utilization as a fungicides substitute was explored against nine resistant microbes. Statistically significant variations were analyzed via one-way analysis of variance (ANOVA) and Kruskal-Wallis test and specific multi comparison tests. Active to highly active inhibition zones manifested the use of biogenic silver nanoparticles as potential candidate for applications in biological arenas and as environmental remediators.

Synthesis and effect of pegylation on citric acid dendritic nano architectures anchored with cefotaxime sodium

In recent years dendrimers have fascinated the investigators towards targeted drug delivery because of their versatile framework and exhibit immense potentiality in entrapping drug moieties through host-guest interactions and serve as a promising vector in biological applications. The current investigation is focused on developing pegylated citric acid cefotaxime dendrimers through the divergent method and its characterization through spectroscopic, microscopic, thermal and microscopic techniques. Among the spectroscopic techniques, ¹H NMR and ¹³C NMR elucidated the key functional groups at various chemical shifts while ESI-MS pointed out the molecular weight of cefotaxime sodium in various generations. Similarly, FTIR, DSC, and AFM investigations detailed that the generations are devoid of incompatibilities, structural deformities and can be opted for targeted drug delivery. The drug entrapment studies and in-vitro drug release studies highlight CFTX G5 containing 92.4% entrapment efficacy and 83.8% drug release in 48 h and specifies a sustain release characteristics. In connection to the above, the in-vivo studies reveal a potent antibacterial activity against various gram-positive and gram-negative microorganisms with a decreased hemolysis and cytotoxicity effects and reflect a high margin of safety regarding pegylated CFTX dendrimers. Further, the antibacterial activities are supported through confocal microscopy that clarified the cellular uptake of dendritic molecules and their internalization.

Low temperature one-pot synthesis of Cu-doped ZnO/Al2O3 composite by a facile rout for rapid methyl orange degradation

ZnO/Al₂O₃ composite modified by 2.5-10wt% Cu were prepared using a set of wet chemical techniques (solvothermal, co-precipitation, ultrasonic and reflux) and characterized. All processes were done under the atmospheric condition and without any calcination step. The product was characterized by PXRD, FE-SEM, FT-IR and UV-Vis spectroscopy. The microscopy images clearly showed lamellar particles morphology in nano regime. X-ray diffraction studies revealed the wurtzite-type ZnO and γ-Al₂O₃ crystallinity. The Band gap varied from 3.20eV for the un-doped Al₂O₃/ZnO sample to 2.18eV for the Al₂O₃/ZnO:Cu with Cu content of 10%. Formed Al₂O₃/ZnO:Cu composite exhibited a supreme photocatalytic performance upon the degradation of methyl orange (MO) under visible-light irradiation. The optimum catalyst indicated completely remove of MO dye with the 15mgL^-1 concentration from the water after 50min photocatalytic reaction time, where for the optimum sample the removal efficiency was 77% after only 10min reaction. Results showed that the inserting of Cu in composite improves the photocatalytic activity of ZnO under visible light. The degradation rate of MO for optimum Cu-doped sample was almost 20 times the un-doped sample.

Isolation of quercetin from the methanolic extract of Lagerstroemia speciosa by HPLC technique, its cytotoxicity against MCF-7 cells and photocatalytic activity

The flavonoids present in the leaves of Lagerstroemia speciosa were extracted, characterized by spectral methods and studied for its cytotoxicity activity against MCF-cell lines and photocatalytic activity against azo dye. Direct and sequential soxhlet extraction was performed and its concentrated crude extract was subjected to high performance liquid chromatography. The yield obtained by the isolated compound (MEI-quercetin) from leaves of L. speciosa was found to be 1.8g from the methanolic extract. The phytochemical analysis and the Rf value of the isolated flavonoid was found to be 3.59. The isolated compound was characterized by Infrared Spectroscopy, NMR and Mass. Based on the characterization, the structure was elucidated as quercetin - a flavonoid. The isolated compound showed the significant in vitro cytotoxicity activity against MCF-7 cell lines at 500μg/ml when compared to the crude extract. Among the various concentrations (25, 50, 100, 250, and 500μg/ml), at higher concentration the cell viability was pronounced and also compared with that of the control. It was first time to report that the isolated flavonoid showed photocatalytic against azo dye-methyl orange. The dye degradation was monitored by UV-Vis spectrophotometry. The isolated compound showed dye degradation of 91.66% with the crude extract 82.47% at 160min. Hence in the present findings, the photocatalytic degradation of MO dye under UV irradiation was investigated over isolated compound of L. speciosa. Hence we expect that this can be used to treat the waste water in near future based on the photocatalytic technique.

Solar catalysed activity against methyl orange dye, cytotoxicity activity of MCF-7 cell lines and identification of marker compound by HPTLC of Lagerstroemia speciosa

The investigation was aimed to quantify the Gallic acid present in Lagerstroemia speciosa leaves (Lythraceae). The High-Performance Thin Layer Chromatography (HPTLC) quantification was performed for acetone (AE), methanolic (ME) and chloroform (CE) extract of leaves of L. speciosa. The pre-coated silica gel 60 F₂₅₄ was used for complete separation of compounds using the mobile phase pet. Ether: ethyl acetate: formic acid (5:5:1v/v).The validation of the extracts was carried out using ICH guidelines for precision, repeatability and accuracy showing the Rf 0.49 against standard Gallic acid. Linearity range for Gallic acid was done from 200 to 1000ng/spot (AE) and200 ng to 600ng/spot (ME), with Correlation, coefficient r=0.99 (AE) and 0.54 (ME) in the said concentrations. The composition in crude leaf extract was determined to be of 49.712mg (AE) and 20.125mg (ME), while it was not found in chloroform extract against standard Gallic acid. Hence the proposed method was very simple, precise, accurate and easy for the screening of the bioactive compounds present in the acetone and methanolic extracts of the leaves of L. speciosa. It was observed that the acetone extract subjected to cytotoxicity showed promising activity at higher concentrations (100 and 200μg/ml) showed 92.9% and 87.13% inhibition against MCF-7 cell lines respectively. The photocatalytic activity of the acetone and methanolic extracts of methyl orange was found to be 90.25% (190min) and 89.03% (180min) respectively. Therefore this can be used as an indicator of purity of herbal drugs and formulation containing L. speciosa.

Photocatalytic activity against azo dye and cytotoxicity on MCF-7 cell lines of zirconium oxide nanoparticle mediated using leaves of Lagerstroemia speciosa

Metal oxide nanoparticles are gaining interest in recent years. The present paper explains about the green synthesis of zirconium oxide nanoparticles (ZrO NPs) mediated from the leaves of Lagerstroemia speciosa. The prepared ZrO NPs were characterized by UV-vis spectroscopy, FT-IR, X-ray diffraction analysis (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX) and Thermogravimetric Analysis (TGA). The photocatalytic activity of ZrO NPs was studied for azo dye by exposing to sunlight. The azo dye was degraded up to 94.58%. Also the ZrO NPs were studied for in vitro cytotoxicity activity against breast cancer cell lines-MCF-7 and evaluated by MTT assay. The cell morphological changes were recorded by light microscope. The cells viability was seen at 500μg/mL when compared against control. Hence the research highlights, that the method was simple, eco-friendly towards environment by phytoremediation activity of the azo dye and cytotoxicity activity against MCF-7 cell lines. Hence the present paper may help to further explore the metal nanoparticle for its potential applications.