Green synthesis, characterization, antibacterial and biofilm inhibitory activity of silver nanoparticles compared to commercial silver nanoparticles

Antibiofilm and Anticancer Activity of Multi-Walled Carbon Nanotubes Fabricated with Hot-Melt Extruded Astaxanthin-Mediated Synthesized Silver Nanoparticles

Purpose

Multi-walled carbon nanotubes (MWCNTs) were used as carriers for silver nanoparticles (AgNPs). In this process, MWCNTs were coated with mesoporous silica (MWCNT-Silica) for uniform and regular loading of AgNPs on the MWCNTs. In addition, astaxanthin (AST) extract was used as a reducing agent for silver ions to enhance the antioxidant, antibiofilm, and anticancer activities of AgNPs. In this process, AST was extracted from Haematococcus pluvialis (H. pluvialis) and processed by hot melt extrusion (HME) to enhance the AST content of H. pluvialis. AST has strong antioxidative properties, which leads to anticancer activity. In addition, AgNPs are well known for their strong antibacterial properties. The antibiofilm and anticancer effects were studied comprehensively by loading the AST AgNPs onto MWCNT-Silica.

Methods

AgNPs-loaded MWCNT-silica (MWCNT-Ag) was prepared through the binding reaction of TSD and silanol groups and the aggregation interaction of Ag and TSD. To enhance the antioxidant, antibiofilm, and anticancer activities of AgNPs, HME-treated H. pluvialis extract (HME-AST) was used as a reducing solution of silver ions. The increased AST content of HME-AST was confirmed by high-performance liquid chromatography (HPLC) analysis, and the total phenol and flavonoid content analysis confirmed that HME enhanced the active components of H. pluvialis. The antibiofilm activity of MWCNT-AST was investigated by biofilm inhibition and destruction test, SEM, and CLSM analysis, and the anticancer activity was investigated by WST assay, fluorescent staining analysis, and flow cytometry analysis.

Results

MWCNT-AST showed higher antioxidant activity and antibiofilm activity than MWCNT-Ag against E. coli, S. aureus, and methicillin-resistant S. aureus (MRSA). MWCNT-AST showed higher anticancer activity against breast cancer cells (MDA-MB-231) than MWCNT-Ag, and lower toxicity in normal cells HaCaT and NIH3T3.

Conclusion

MWCNT-AST exhibits higher antioxidant, antibiofilm, and anticancer activities than MWCNT-Ag, and exhibits lower toxicity to normal cells.

Antifungal potential of silver nanoparticles stabilized with the flavonoid naringenin

Introduction. Fungal infections caused by yeast have increased in recent decades, becoming a major threat to public health.Hypothesis/Gap Statement. Antifungal therapy represents a challenging problem because, in addition to presenting many side effects, fungal resistance has been increasing in recent years. As a result, the search for new therapeutic agents has advanced with the use of new technologies such as nanoparticles (NPs).Aim. Synthesize, characterize and evaluate the antifungal potential of naringenin (NAR)-stabilized silver NPs.Methodology. The biosynthesis of NPs was stabilized using the NAR molecule and an aqueous solution of silver nitrate. The characterization of silver nanoparticles (AgNPs) was performed using different methods, which include UV-visible spectroscopy, powder X-ray diffraction (XRD), transmission electron microscopy, zeta potential measurements and Fourier transform infrared (FTIR) spectroscopy. Antifungal activity was evaluated against clinical isolates of Candida albicans by determining the MIC and the minimum fungicidal concentration (MFC).Results. The AgNP NAR showed a colloidal appearance with an average size of 14.71 nm and zeta potential measured at -33.3 mV, indicating a highly stable suspension. XRD analysis confirmed the crystal structure. FTIR spectra showed the presence of several functional groups of plant compounds, which play an important role in the coating and bioreduction processes. The antifungal activity against C. albicans showed an MIC of 3.55 µg ml-1 and an MFC of 7.1 µg ml-1. According to the growth kinetic assay in 12 h, there was a reduction of ~50% (<3 log10). Furthermore, AgNP NAR did not show mutagenic potential.Conclusion. The AgNP NAR obtained presented ideal characteristics for biomedical applications, good stability and promising antimicrobial activity.

Green Silver Nanoparticles: An Antibacterial Mechanism

Silver nanoparticles (AgNPs) are a promising tool in the fight against pathogenic microorganisms. "Green" nanoparticles are especially valuable due to their environmental friendliness and lower energy consumption during production, as well as their ability to minimize the number of toxic by-products. This review focuses on the features of AgNP synthesis using living organisms (bacteria, fungi, plants) and the involvement of various biological compounds in this process. The mechanism of antibacterial activity is also discussed in detail with special attention given to anti-biofilm and anti-quorum sensing activities. The toxicity of silver nanoparticles is considered in light of their further biomedical applications.

Antimicrobial and Antibiofilm Activity of Green Synthesized Silver Nanoparticles by Using In Vitro Grown Aloe vera L

In this study, in vitro grown Aloe vera L. tissues were used for AgNP synthesis. Adventitious root and callus tissues were grown in MS medium containing 1 mg/L IAA and 1 mg/L NAA. Using A. vera L. leaf, in vitro grown callus, and adventitious roots tissue extracts, AgNPs were synthesized. According to DLS analysis, PDI values and zeta potential values showed that AgNPs from adventitious root were more suitable in terms of size and surface charge. Characterization of adventitious root-derived AgNPs was performed by UV-Vis absorption spectrum, ICP/MS, SEM, FTIR, and XRD. According to HPLC results, catechin, gentisic acid, caffeic acid, coumaric acid, polydatin, coumarin, and ellagic acid were found in adventitious roots. Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC2 7853), MRSA (ATCC 33951) and Staphylococcus aureus (ATCC 6538) strains were used to determine the antibacterial and antibiofilm activity of AgNPs. The highest antibacterial activity was determined against P. aeruginosa. Lower concentrations of AgNPs caused changes in the structure of the biofilm formed by P. aeruginosa, which produced particularly strong biofilms, resulting in failure of biofilm maturation. Accordingly, AgNPs synthesized from Aloe vera L. adventitious roots had antibacterial and antibiofilm activity even at low concentrations against the tested bacterial strains.

Analysis of Eremostachys hyoscyamoides essential oil composition and assessing the antibacterial and antioxidant properties of the ethanol extract

The increasing issue of antibiotic resistance in bacterial infections has led to challenging and costly treatments. Free radicals significantly contribute to the progression of several diseases, such as cardiometabolic disorders, neurodegenerative conditions, and cancers. Antioxidants can help alleviate or prevent these health problems. This research aimed to assess the antibacterial and antioxidant effects of Eremostachys hyoscyamoides ethanol extract. Additionally, the chemical profile of the essential oil obtained from the aerial parts of E. hyoscyamoides was characterized through gas chromatography-mass spectrometry (GC-MS). The extract's antibacterial effect was tested against three Gram-positive bacteria (Micrococcus luteus, Staphylococcus epidermidis, and S. aureus), in addition to three Gram-negative bacteria (Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli). The cup-plate method was employed to assess the antibacterial activity, which was subsequently followed by the determination of the minimum inhibitory concentration through the agar dilution method. To evaluate the antioxidant effects, the DPPH radical scavenging assay was used. The total phenolic content (TPC) and flavonoid content (TFC) of the extract were quantified using the Folin Ciocalteu and Aluminum Chloride methods as spectrophotometric-based techniques, respectively. The essential oil of E. hyoscyamoides was extracted via hydrodistillation and subjected to GC-MS analysis. The findings demonstrated that the ethanol extract of E. hyoscyamoides effectively inhibited the growth of the bacterial strains examined. The IC50 value measured in the DPPH test was 48.194 ± 0.61 μg/mL. The TPC was found to be 84.15 ± 2.5 mg GAE/g, while the TFC was determined to be 19.35 ± 1.3 mg RE/g. A total of 50 components, accounting for 93.6 % of the essential oil composition, were identified. High concentrations of elemol (6.8 %), 2,4-di-tert-butylphenol (10.7 %), and linalyl acetate (4.2 %) were putatively identified in the essential oil. In conclusion, the ethanol extract of E. hyoscyamoides exhibited hopeful potential as a natural source of antioxidants and antibacterial agents.

Sustainable and facile fabrication of chitosan-coated silver-doped zinc oxide nanocomposites exploiting Bergera koenigii foliage for enhanced photocatalysis and antibacterial activity

Industrial and academic chemical pollutants such as Eriochrome Black-T (EBT) and murexide dyes are widely used in academic institution as well as industries, when eluted into rivers, delineate the ill effect on human and aquatic life. Herein, green and ecofriendly synthesis of silver doped-Zinc oxide nanoparticles (Ag/ZnO NPs) and chitosan coated Ag/ZnO nanoparticles (CS/Ag/ZnO NPs) using Bergera koenigii extract to solve environmental issues have been reported for the first time. Spherical and agglomerated particles with crystalline flakes like morphology of Ag/ZnO NPs and CS/Ag/ZnO NPs respectively have been ascertained by Scanning electron morphology (SEM) analyses and XRD. XRD analysis revealed the average crystallite size of 42.16 nm and 48.45 nm for Ag/ZnO NPs with 5 % and 10 % Ag concentration respectively, lesser than crystallite size of 47.394 nm and 52.38 nm for CS-5 % Ag/ZnO NC and CS-10 % Ag/ZnO NC respectively. All the synthesized NPs and NC demonstrated remarkable antibacterial potential against both gram +ve and gram -ve bacteria. Additionally, all the materials showed very high time-dependent photocatalytic degradation activity (>98 %) of EBT and murexide in 12 min. Remarkably, all active nano-catalysts exhibit high durability, and displayed recyclability for >8 cycles. In nutshell, chitosan coated nano-catalyst showed drastic improvement in photocatalytic and antibacterial activities.

Recent Progress in Terrestrial Biota Derived Antibacterial Agents for Medical Applications

Conventional antibiotic and multidrug treatments are becoming less and less effective and the discovery of new effective and safe antibacterial agents is becoming a global priority. Returning to a natural antibacterial product is a relatively new current trend. Terrestrial biota is a rich source of biologically active substances whose antibacterial potential has not been fully utilized. The aim of this review is to present the current state-of-the-art terrestrial biota-derived antibacterial agents inspired by natural treatments. It summarizes the most important sources and newly identified or modified antibacterial agents and treatments from the last five years. It focuses on the significance of plant- animal- and bacteria-derived biologically active agents as powerful alternatives to antibiotics, as well as the advantages of utilizing natural antibacterial molecules alone or in combination with antibiotics. The main conclusion is that terrestrial biota-derived antibacterial products and substances open a variety of new ways for modern improved therapeutic strategies. New terrestrial sources of known antibacterial agents and new antibacterial agents from terrestrial biota were discovered during the last 5 years, which are under investigation together with some long-ago known but now experiencing their renaissance for the development of new medical treatments. The use of natural antibacterial peptides as well as combinational therapy by commercial antibiotics and natural products is outlined as the most promising method for treating bacterial infections. In vivo testing and clinical trials are necessary to reach clinical application.

Silver Nanoparticles in Therapeutics and Beyond: A Review of Mechanism Insights and Applications

Silver nanoparticles (NPs) have become highly promising agents in the field of biomedical science, offering wide therapeutic potential due to their unique physicochemical properties. The unique characteristics of silver NPs, such as their higher surface-area-to-volume ratio, make them ideal for a variety of biological applications. They are easily processed thanks to their large surface area, strong surface plasmon resonance (SPR), stable nature, and multifunctionality. With an emphasis on the mechanisms of action, efficacy, and prospective advantages of silver NPs, this review attempts to give a thorough overview of the numerous biological applications of these particles. The utilization of silver NPs in diagnostics, such as bioimaging and biosensing, as well as their functions in therapeutic interventions such as antimicrobial therapies, cancer therapy, diabetes treatment, bone repair, and wound healing, are investigated. The underlying processes by which silver NPs exercise their effects, such as oxidative stress induction, apoptosis, and microbial cell membrane rupture, are explored. Furthermore, toxicological concerns and regulatory issues are discussed, as well as the present difficulties and restrictions related to the application of silver NPs in medicine.

Combating bacterial biofilms and related drug resistance: Role of phyto-derived adjuvant and nanomaterials

The emergence of antimicrobial resistance (AMR) in clinical microbes has led to a search for novel antibiotics for combating bacterial infections. The treatment of bacterial infections becomes more challenging with the onset of biofilm formation. AMR is further accelerated by biofilm physiology and differential gene expression in bacteria with an inherent resistance to conventional antibiotics. In the search for innovative strategies to control the spread of AMR in clinical isolates, plant-derived therapeutic metabolites can be repurposed to control biofilm-associated drug resistance. Unlike antibiotics, designed to act on a single cellular process, phytochemicals can simultaneously target multiple cellular components. Furthermore, they can disrupt biofilm formation and inhibit quorum sensing, offering a comprehensive approach to combat bacterial infections. In bacterial biofilms, the first line of AMR is due to biofilms associated with the extracellular matrix, diffusion barriers, quorum sensing, and persister cells. These extracellular barriers can be overcome using phytochemical-based antibiotic adjuvants to increase the efficacy of antibiotic treatment and restrict the spread of AMR. Furthermore, phytochemicals can be used to target bacterial intracellular machinery such as DNA replication, protein synthesis, efflux pumps, and degrading enzymes. In parallel with pristine phytochemicals, phyto-derived nanomaterials have emerged as an effective means of fighting bacterial biofilms. These nanomaterials can be formulated to cross the biofilm barriers and function on cellular targets. This review focuses on the synergistic effects of phytochemicals and phyto-derived nanomaterials in controlling the progression of biofilm-related AMR. IT provides comprehensive insights into recent advancements and the underlying mechanisms of the use of phyto-derived adjuvants and nanomaterials.

Phytosynthesis of Silver Nanoparticles Using Mansoa alliacea (Lam.) A.H. Gentry (Bignoniaceae) Leaf Extract: Characterization and Their Biological Activities

Background. Mansoa alliacea is a native plant renowned for its medicinal properties in traditional healing in the Amazon Region. This plant is rich in polyphenols, flavonoids, anthocyanins, phenolic acids, tannins, ketones, triterpenes, as well as other bioactive compounds. Objectives. This study aims to develop an innovative, eco-friendly method for synthesizing silver nanoparticles using an aqueous extract of M. alliacea (Ma-AgNPs), enhancing the biological activities of AgNPs by leveraging the therapeutic potential of the plant's bioactive compounds. Methods. Silver nanoparticles were synthesized using the aqueous extract of M. alliacea. The biological activities of Ma-AgNPs were assessed, including antibacterial, anti-inflammatory, antioxidant, antitumor, and anti-biofilm effects, along with evaluating their hemolytic activity. Results. Quantitative analysis revealed that Ma-AgNPs exhibit potent antibacterial activity against multidrug and non-multidrug-resistant bacteria, with MIC values ranging from 1.3 to 10.0 µg/mL. The Ma-AgNPs significantly reduced NO production by 86.9% at 4 µg/mL, indicating strong anti-inflammatory effects. They demonstrated robust antioxidant activity with an IC50 of 5.54 ± 1.48 µg/mL and minimal hemolytic activity, with no hemolysis observed up to 20 µg/mL and only 4.5% at 40 µg/mL. Their antitumor properties were notable, with IC50 values between 2.9 and 5.4 µg/mL across various cell lines, and they achieved over 50% biofilm inhibition at concentrations of 30-40 µg/mL. Conclusions. These findings underscore the potential of Ma-AgNPs for biomedical applications, particularly in developing new antimicrobial agents and bioactive coatings with reduced toxicity. This research highlights a sustainable approach that not only preserves but also amplifies the inherent biological activities of plant extracts, paving the way for innovative therapeutic solutions.

Bactericidal behavior of silver nanoparticle decorated nano-sized magnetic hydroxyapatite

Methicillin-resistant Staphylococcus aureus (MRSA) is the most common cause of acute bacterial arthritis. Due to the increase in antibiotic resistance in these bacteria, the discovery of new antibacterial agents has become one of the hot topics in the scientific community. Here, we prepared a nano-sized porous biocompatible magnetic hydroxyapatite through a solvothermal method. Then, we adopted a post-synthesis modification strategy to modify its surface for the stabilization of Ag NPs through a green reduction by the euphorbia plant extract. Moreover, the results show that the prepared composite perfectly prevents the aggregation of Ag NPs. This composite was used as a bactericidal and antibiofilm agent against MRSA bacteria in an in vitro environment, which showed excellent results. Also, the cell viability assay indicates that the prepared composite has low cytotoxicity, making it a perfect antibacterial agent for in vivo experiments.

Inorganic nanoparticles: An effective antibiofilm strategy

Biofilm is a common problem associated with human health. Pathogenicity and increase in resistance of bacteria require urgent development of effective ways for the treatment of bacterial diseases. Different strategies have been developed for the treatment of bacterial infections among which nanoparticles have shown greater prospects in battling with infections. Biofilms are resistant microbial colonies that possess resistance and, hence, cannot be killed by conventional drugs. Nanoparticles offer new avenues for treating biofilm-related infections involving multi-drug resistant organisms. They possess great antibiofilm properties, disrupting cell architecture and preventing colony formation. Green-synthesised nanoparticles are more effective and less toxic to human cells than commercially available or chemically synthesised antibiofilm nanoparticles. This review summarises the antibiofilm efficiency of plant-mediated nanoparticles and knowledge about biofilm inhibition.

Application of nanoparticles in breast cancer treatment: a systematic review

It is estimated that cancer is the second leading cause of death worldwide. The primary or secondary cause of cancer-related mortality for women is breast cancer. The main treatment method for different types of cancer is chemotherapy with drugs. Because of less water solubility of chemotherapy drugs or their inability to pass through membranes, their body absorbs them inadequately, which lowers the treatment's effectiveness. Drug specificity and pharmacokinetics can be changed by nanotechnology using nanoparticles. Instead, targeted drug delivery allows medications to be delivered to the targeted sites. In this review, we focused on nanoparticles as carriers in targeted drug delivery, their characteristics, structure, and the previous studies related to breast cancer. It was shown that nanoparticles could reduce the negative effects of chemotherapy drugs while increasing their effectiveness. Lipid-based nanocarriers demonstrated notable results in this instance, and some products that are undergoing various stages of clinical trials are among the examples. Nanoparticles based on metal or polymers demonstrated a comparable level of efficacy. With the number of cancer cases rising globally, many researchers are now looking into novel treatment approaches, particularly the use of nanotechnology and nanoparticles in the treatment of cancer. In order to help clinicians, this article aimed to gather more information about various areas of nanoparticle application in breast cancer therapy, such as modifying their synthesis and physicochemical characterization. It also sought to gain a deeper understanding of the mechanisms underlying the interactions between nanoparticles and biologically normal or infected tissues.

Advances in silver nanoparticles: a comprehensive review on their potential as antimicrobial agents and their mechanisms of action elucidated by proteomics

Nanoparticles play a crucial role in the field of nanotechnology, offering different properties due to their surface area attributed to their small size. Among them, silver nanoparticles (AgNPs) have attracted significant attention due to their antimicrobial properties, with applications that date back from ancient medicinal practices to contemporary commercial products containing ions or silver nanoparticles. AgNPs possess broad-spectrum biocidal potential against bacteria, fungi, viruses, and Mycobacterium, in addition to exhibiting synergistic effects when combined with certain antibiotics. The mechanisms underlying its antimicrobial action include the generation of oxygen-reactive species, damage to DNA, rupture of bacterial cell membranes and inhibition of protein synthesis. Recent studies have highlighted the effectiveness of AgNPs against various clinically relevant bacterial strains through their potential to combat antibiotic-resistant pathogens. This review investigates the proteomic mechanisms by which AgNPs exert their antimicrobial effects, with a special focus on their activity against planktonic bacteria and in biofilms. Furthermore, it discusses the biomedical applications of AgNPs and their potential non-preparation of antibiotic formulations, also addressing the issue of resistance to antibiotics.

Study on the inhibitory activity and mechanism of Mentha haplocalyx essential oil nanoemulsion against Fusarium oxysporum growth

Mentha haplocalyx essential oil (MEO) has demonstrated inhibitory effects on Fusarium oxysporum. Despite its environmentally friendly properties as a natural product, the limited water solubility of MEO restricts its practical application in the field. The use of nanoemulsion can improve bioavailability and provide an eco-friendly approach to prevent and control Panax notoginseng root rot. In this study, Tween 80 and anhydrous ethanol (at a mass ratio of 3) were selected as carriers, and the ultrasonic method was utilized to produce a nanoemulsion of MEO (MNEO) with an average particle size of 26.07 nm. Compared to MTEO (MEO dissolved in an aqueous solution of 2% DMSO and 0.1% Tween 80), MNEO exhibited superior inhibition against F. oxysporum in terms of spore germination and hyphal growth. Transcriptomics and metabolomics results revealed that after MNEO treatment, the expression levels of certain genes related to glycolysis/gluconeogenesis, starch and sucrose metabolism were significantly suppressed along with the accumulation of metabolites, leading to energy metabolism disorder and growth stagnation in F. oxysporum. In contrast, the inhibitory effect from MTEO treatment was less pronounced. Furthermore, MNEO also demonstrated inhibition on meiosis, ribosome function, and ribosome biogenesis in F. oxysporum growth process. These findings suggest that MNEO possesses enhanced stability and antifungal activity, which effectively hinders F. oxysporum through inducing energy metabolism disorder, meiotic stagnation, as well as ribosome dysfunction, thus indicating its potential for development as a green pesticide for prevention and control P. notoginseng root rot caused by F.oxyosporum.

Insight into the molecular mechanism, cytotoxic, and anticancer activities of phyto-reduced silver nanoparticles in MCF-7 breast cancer cell lines

This contribution insight on the cytotoxic and anticancer activities and molecular mechanism of phyto-reduced silver nanoparticles (AgNPs) in MCF-7 breast cancer cell lines. A simple, entirely green synthesis process was optimized for the phyto-reduction of AgNP (~12.7 nm) using aqueous leaf extracts of Indigofera heterantha. The structural and vibrational properties of biosynthesized AgNPs were extensively characterized using UV-Vis spectrophotometer, x-ray diffraction (XRD), dynamic light scattering (DLS), and Fourier transform Infrared spectroscopy (FTIR), while their shape and morphology was studied through scanning electron microscopy (SEM). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay indicates concentration dependent inhibition with IC50, 27.93 ± 2.10 μg/mL against MCF-7 cells and 294.38 ± 3.87 μg/mL against L929 cells. The manifested anticancer mechanism in MCF-7 cells was extensively studied using Acridine orange/ethidium bromide (AO/EB), 4',6-diamidino-2-phenylindole (DAPI) and Annexin-V/propedium iodide fluorescence microscopic assays. The level of reactive oxygen species (ROS) was measured using DCFH-DA fluorescent spectroscopy. Overall, the results show that AgNPs exhibit cytotoxic and apoptotic effect on breast cancer MCF-7 cells by damaging membrane integrity and nuclear fragmentation due to oxidative stress generated by elevated level of ROS. RESEARCH HIGHLIGHTS: Biomimetic synthesis of nano dimension size silver nanoparticles (AgNPs). Characterization of AgNPs through UV-Vis, DLS, XRD, FTIR, and SEM. Cytotoxic and anticancer effects of the biosynthesized AgNPs in L929 fibroblast cells and MCF7 breast cancer respectively. Determination of morphological, and nuclear changes triggered by AgNPs in MCF 7 breast cancer cells using fluorescent microscopy and flow cytometry. Apoptosis induction by AgNPs in cancer cells through oxidative stress generated by reactive oxygen species (ROS).

UPLC-qTOF-MS phytochemical profile of Commiphora gileadensis leaf extract via integrated ultrasonic-microwave-assisted technique and synthesis of silver nanoparticles for enhanced antibacterial properties

The utilization of metallic nanoparticles in bio-nanofabrication holds significant potential in the field of applied research. The current study applied and compared integrated ultrasonic-microwave-assisted extraction (US/MICE), ultrasonic extraction (USE), microwave-assisted extraction (MICE), and maceration (MAE) to extract total phenolic content (TPC). In addition, the study examined the antioxidant activity of Commiphora gileadensis (Cg) leaf. The results demonstrated that the TPC of US/MICE exhibited the maximum value at 59.34 ± 0.007 mg GAE/g DM. Furthermore, at a concentration of 10 μg/mL, TPC displayed a significant scavenging effect on DPPH (56.69 %), with an EC50 (6.48 μg/mL). Comprehensive metabolite profiling of the extract using UPLC-qTOF-MS/MS was performed to identify active agents. A total of 64 chromatographic peaks were found, out of which 60 were annotated. The most prevalent classes of metabolites found were polyphenols (including flavonoids and lignans), organic compounds and their derivatives, amides and amines, terpenes, and fatty acid derivatives. Transmission electron microscopy (TEM) revealed the aggregate size of the synthesized nanoparticles and the spherical shape of C. gileadensis-mediated silver nanoparticles (Cg-AgNPs). The nanoparticles had a particle size ranging from 7.7 to 42.9 nm. The Cg-AgNPs exhibited more inhibition zones against S. aureus and E. coli. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Cg-extract, AgNPs, and Cg-AgNPs were also tested. This study demonstrated the feasibility of using combined ultrasonic-microwave-assisted extraction to separate and extract chemicals from C. gileadensis on a large scale. These compounds have potential use in the pharmaceutical industry. Combining antibacterial and biocompatible properties in materials is vital for designing new materials for biomedical applications. Additionally, the results showed that the biocompatibility of the Ag-NPs using C. gileadensis extracts demonstrated outstanding antibacterial properties.

The effect of classroom-based assessment (CBA) on Chinese EFL learners' speaking performance, engagement, and willingness to communicate: Undergraduate students' perceptions

CBA has emerged as a prominent pedagogical approach aimed at intertwining assessment within the instructional process, effectively fostering student learning. In English as a Foreign Language (EFL) education, CBA has garnered considerable attention, given its potential to enhance language learners' engagement, speaking proficiency, and willingness to communicate. This mixed-method research study delves into the impact of Classroom-Based Assessment (CBA) on the speaking performance, engagement, and willingness to communicate of undergraduate Chinese EFL learners. The study involved 90 Chinese EFL learners in the quantitative phase and 25 in the qualitative phase. Data collection comprised three questionnaires and an interview checklist. The data analysis employed inferential statistics (t-tests) for the quantitative data and thematic analysis for the qualitative insights. The findings of this study reveal that CBA exerts a significant influence on language learners' engagement, speaking abilities, and willingness to communicate. The quantitative results, as indicated by t-tests, indicate noteworthy improvements in these key aspects when CBA is integrated into the classroom environment. Moreover, the qualitative phase of the study, employing thematic analysis, uncovered five distinct ways through which CBA impacts the main variables under investigation. This research elucidates the multifaceted influence of CBA on undergraduate Chinese EFL learners. It not only demonstrates the quantitative impact on engagement, speaking skills, and willingness to communicate but also offers valuable qualitative insights into the diverse ways through which CBA enhances the language learning experience. These findings underscore the significance of integrating CBA into EFL classrooms as a potent tool for optimizing learner outcomes.

Comparative investigation on chemical and green synthesized titanium dioxide nanoparticles against chromium (VI) stress eliciting differential physiological, biochemical, and cellular attributes in Helianthus annuus L

Nanotechnology is a new scientific area that promotes unique concepts to comprehend the optimal mechanics of nanoparticles (NPs) in plants under heavy metal stress. The present investigation focuses on effects of synthetic and green synthesized titanium dioxide nanoparticles (TiO2 NPs and gTiO2 NPs) against Cr(VI). Green TiO2 NPs have been produced from plant leaf extract (Ricinus communis L.). Synthesis was confirmed employing an array of optical spectroscopic and electron microscopic techniques. Chromium strongly accelerated H2O2 and MDA productions by 227 % and 266 % at highest chromium concentration (60 mg/kg of soil), respectively, and also caused DNA damage, and decline in photosynthesis. Additionally, anomalies were observed in stomatal cells with gradual increment in chromium concentrations. Conversely, foliar applications of TiO2 NPs and gTiO2 NPs considerably mitigated chromium stress. Sunflower plants treated with modest amounts of green TiO2 NPs had significantly better growth index compared to chemically synthesized ones. Principal component analysis highlighted the variations among photosynthetic attributes, oxidative stress markers, and antioxidant defense systems. Notably, gTiO2 supplementation to the Cr(VI) strained plants minimized PC3 production which is a rare report so far. Conclusively, gTiO2 NPs have been identified to be promising nano-based nutrition resource for farming applications.

Green synthesis of silver nanoparticles and evaluation of their effects on the Porphyromonas gingivalis bacterial biofilm formation

OBJECTIVE

This study aimed to evaluate the impact of silver nanoparticles (AgNPs) synthesized from propolis on the formation of Porphyromonas gingivalis biofilms.

MATERIAL AND METHODS

AgNPs were synthesized from propolis, and their inhibitory effect on P. gingivalis biofilm formation was assessed. Different concentrations of AgNPs (0.1%, 0.3%, and 0.5%) were tested to determine the dose-dependent antibacterial activity.

RESULTS

The results of this study indicated that AgNPs exhibited an inhibitory effect on P. gingivalis biofilm formation. The antibacterial activity of AgNPs was dose-dependent, with concentrations of 0.1%, 0.3%, and 0.5% showing effectiveness. Notably, the concentration of 0.5% demonstrated the most significant anti-biofilm formation activity.

CONCLUSION

The results of this study suggest that AgNPs synthesized from propolis have potential as an effective option for enhancing periodontal treatment outcomes. The inhibitory effect of AgNPs on P. gingivalis biofilm formation highlights their potential as alternative antimicrobial agents in the management of periodontal diseases.

Exploring the Biofilm Inhibition Potential of a Novel Phytic Acid-Crosslinked Chitosan Nanoparticle: In Vitro and In Vivo Investigations

The primary factor underlying the virulence of Candida albicans is its capacity to form biofilms, which in turn leads to recurrent complications. Over-the-counter antifungal treatments have proven ineffective in eliminating fungal biofilms and the inflammatory cytokines produced during fungal infections. Chitosan nanoparticles offer broad and versatile therapeutic potential as both antifungal agents and carriers for antifungal drugs to combat biofilm-associated Candida infections. In our study, we endeavoured to develop chitosan nanoparticles utilising chitosan and the antifungal crosslinker phytic acid targeting C. albicans. Phytic acid, known for its potent antifungal and anti-inflammatory properties, efficiently crosslinks with chitosan. The nanoparticles were synthesised using the ionic gelation technique and subjected to analyses including Fourier transform infrared spectroscopy, dynamic light scattering, and zeta potential analysis. The synthesised nanoparticles exhibited dimensions with a diameter (Dh) of 103 ± 3.9 nm, polydispersity index (PDI) of 0.33, and zeta potential (ZP) of 37 ± 2.5 mV. These nanoparticles demonstrated an antifungal effect with a minimum inhibitory concentration (MIC) of 140 ± 2.2 µg/mL, maintaining cell viability at approximately 90% of the MIC value and reducing cytokine levels. Additionally, the nanoparticles reduced ergosterol content and exhibited a 62% ± 1.2 reduction in biofilm susceptibility, as supported by colony-forming unit (CFU) and XTT assays-furthermore, treatment with nanoparticles reduced exopolysaccharide production and decreased secretion of aspartyl protease by C. albicans. Our findings suggest that the synthesised nanoparticles effectively combat Candida albicans infections. In vivo studies conducted on a mouse model of vaginal candidiasis confirmed the efficacy of the nanoparticles in combating fungal infections in vivo.

Exploring the antibiofilm and toxicity of tin oxide nanoparticles: Insights from in vitro and in vivo investigations

BACKGROUND INFORMATION

The advancement of biological-mediated nanoscience towards higher levels and novel benchmarks is readily apparent, owing to the use of non-toxic synthesis processes and the incorporation of various additional benefits. This study aimed to synthesize stable tin oxide nanoparticles (SnO2-NPs) using S. rhizophila as a mediator.

METHODS

The nanoparticles that were created by biosynthesis was examined using several analytical techniques, including Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), UV-visible (UV-vis) spectroscopy, and energy dispersive X-ray spectroscopy (EDS).

RESULTS

The results obtained from the characterization techniques suggest that S. rhizophila effectively catalyzed the reduction of SnCl2 to SnO2-NPs duration of 90 min at ambient temperature with the ƛmax of 328 nm. The size of the nano crystallite formations was measured to be 23 nm. The present study investigates nanoscale applications' antibacterial efficacy against four bacterial strains, including Klebsiella Sp, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The observed zone of inhibition for the nanoparticles (NPs) varied from 10 to 25 mm. The research findings demonstrate that the nanoparticles (NPs) are effective as antibacterial, phytotoxic, and cytotoxic agents.

Recent updates and feasibility of nanodrugs in the prevention and eradication of dental biofilm and its associated pathogens-A review

OBJECTIVES

Dental biofilm is one of the most prevalent diseases in humans, which is mediated by multiple microorganisms. Globally, half of the human population suffers from dental biofilm and its associated diseases. In recent trends, nano-formulated drugs are highly attractive in the treatment of dental biofilms. However, the impact of different types of nanodrugs on the dental biofilm and its associated pathogens have not been published till date. Thus, this review focuses on the recent updates, feasibility, mechanisms, limitations, and regulations of nanodrugs applications in the prevention and eradication of dental biofilm.

STUDY SELECTION, DATA AND SOURCES

A systematic search was conducted in PubMed/Google Scholar/Scopus over the past five years covering the major keywords "nanodrugs, metallic nanoparticles, metal oxide nanoparticles, natural polymers, synthetic polymers, biomaterials, dental biofilm, antibiofilm mechanism, dental pathogens", are reviewed in this study. Nearly, 100 scientific articles are selected in this relevant topic published between 2019 and 2023. Data from the selected studies dealing with nanodrugs used for biofilm treatment was qualitatively analyzed.

CONCLUSIONS

The nanodrugs such as silver nanoparticles, gold nanoparticles, selenium nanoparticles, zinc oxide nanoparticles, copper oxide nanoparticles, titanium oxide nanoparticles, hydroxyapatite nanoparticles and these inorganic nanoparticles incorporated polymer-based nanocomposites, organic/inorganic nanoparticles mediated antimicrobial photodynamic therapy exhibits an excellent antibacterial and antibiofilm activity towards dental pathogens. Finally, this review highlights that bioinspired nanodrugs will be very useful to control the dental biofilm and its associated diseases.

CLINICAL SIGNIFICANCE

Microbial influence on the oral environment is unavoidable; therefore, curing such dental biofilms and pathogens is essential for the impactful reflection of applying biocompatible treatments. In this direction, the current review explains the demand for the nanodrug in inhibiting biofilms for the effective exploration of employing treatments.

Process optimization for green synthesis of silver nanoparticles using Rubus discolor leaves extract and its biological activities against multi-drug resistant bacteria and cancer cells

Multi-drug resistant (MDR) bacteria are considered a serious public health threat. Also, increasing rate of resistance to anticancer drugs, as well as their toxicity, is another point of concern. Therefore, the new antibacterial and anticancer agents are always needed. The synthesizing silver nanoparticles (AgNPs) using medicinal plants, is an effective approach for developing novel antibacterial and anticancer agents. Rubus discolor, a native species of the Caucasus region, produces leaves that are typically discarded as a by-product of raspberry production. The present study has focused on optimizing the green synthesis of AgNPs using R. discolor leaves extract through response surface methodology. The optimal values for AgNPs synthesis were an AgNO3 concentration of 7.11 mM, a time of 17.83 h, a temperature of 56.51 °C, and an extract percentage of 29.22. The production of AgNPs was confirmed using UV-visible spectroscopy (λmax at 456.01 nm). TEM analysis revealed well-dispersed AgNPs (an average size of 37 nm). The XRD analysis confirmed the crystalline structure. The EDX detected a strong peak at 3 keV corresponded to Ag. The zeta potential value (- 44.2 mV) indicated the stability of nanoparticles. FT-IR spectra showed the presence of various functional groups from plant compounds, which play an important role in the capping and bio-reduction processes. The AgNPs revealed impressive antibacterial activities against MDR Escherichia coli and Pseudomonas aeruginosa (MIC ranging from 0.93 to 3.75 mg ml-1). The phytochemical analysis indicated the presence of phenolics, tannins, and flavonoids on the surface of AgNPs. They also showed significant cytotoxic effects on A431, MCF-7, and HepG2 cells (IC50 values ranging from 11 to 49.1 µg ml-l).

Digital communication activities and EFL learners' willingness to communicate and engagement: Exploring the intermediate language learners' perceptions

EFL/ESL teachers have used digital communication activities to teach language skills. However, the effect of digital communication activities on EFL learners' Willingness to Communicate (WTC) in classrooms and learner engagement has yet to be well investigated. This study examined the influence of digital communication activities on the engagement and willingness to communicate of intermediate English as a Foreign Language (EFL) learners. It also assessed the potential advantages of integrating digital communication into language learning contexts. A mixed-methods approach involving pretest-posttest comparisons and qualitative interviews was employed. In the quantitative phase, four intact classes of 80 intermediate Chinese EFL learners were recruited and assigned to control and experimental groups. They attempted the scales (WTC and engagement) before and after treatment. However, 20 EFL learners exposed to digital communication activities were interviewed. The research revealed notable enhancements in affective, cognitive, and behavioral engagement among the experimental group. Moreover, a substantial positive effect on EFL learners' willingness to communicate was observed, particularly in speaking, writing, reading, and comprehension activities. Findings have practical implications for EFL teachers and learners to use digital communication activities to enhance the learners' WTC in the classroom and different aspects of engagement.

Açaí (Euterpe oleracea Mart.) green synthesis of silver nanoparticles: antimicrobial efficacy and ecotoxicological assessment

The synthesis of silver nanoparticles (AgNPs) is usually based on expensive methods that use or generate chemicals that can negatively impact the environment. Our study presents a simple one-step synthesis process for obtaining AgNP using an aqueous extract of Amazonian fruit açai (Euterpe oleracea Mart.) as the reducing and stabilizing agents. The bio-synthesized AgNP (bio-AgNP) were comprehensively characterized by diverse techniques, and as a result, 20-nm spherical particles (transmission electron microscopy) were obtained. X-ray diffraction analysis (XRD) confirmed the presence of crystalline AgNP, and Fourier-transform infrared spectroscopy (FT-IR) suggested that polyphenolic compounds of açaí were present on the surface. The bio-AgNP showed antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii. In Caenorhabditis elegans exposed to 10 μg/L bio-AgNP for 96 h, there were no significant effects on growth, reproduction, or reactive oxygen species (ROS) concentration; however, there was an increase in superoxide dismutase (SOD) and glutathione-S-transferase (GST) enzymatic activity. In contrast, when worms were exposed to chemically synthesized AgNP (PVP-AgNP), an increase in ROS, SOD, and GST activity and a reduction in oxidative stress resistance were observed. In conclusion, our study not only showcased the potential of açaí in the simple and rapid production of AgNP but also highlighted the broad-spectrum antimicrobial activity of the synthesized nanoparticles using our protocol. Moreover, our findings revealed that these AgNPs exhibited reduced toxicity to C. elegans at environmentally realistic concentrations compared with PVP-AgNP.

Antibacterial, antioxidant, and anticancer potential of green fabricated silver nanoparticles made from Viburnum grandiflorum leaf extract

BACKGROUND

Recently, researchers are focusing on creating new tools to combat the antibiotic resistant bacteria and malignancy issues, which pose significant threats to humanity. Biosynthesized silver nanoparticles (AgNPs) are thought to be a potential solution to these issues. The biosynthesis method, known for its environmentally friendly and cost-effective characteristics, can produce small-sized AgNPs with antimicrobial and anticancer properties. In this study, AgNPs were bio-fabricated from the distilled water and methanolic extracts of Viburnum grandiflorum leaves. Physio-chemical characterization of the bio-fabricated AgNPs was conducted using UV-visible spectroscopy, scanning electron microscopy, energy dispersive X-ray, and X-ray diffraction analysis.

RESULTS

AgNPs produced from the methanol extract were smaller in size (12.28 nm) compared to those from the aqueous extract (17.77 nm). The bioengineered AgNPs exhibited a circular shape with a crystalline nature. These biosynthesized AgNPs demonstrated excellent bactericidal activity against both gram-negative (Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria. Highest antibacterial activity was observed with the methanol extract against P. aeruginosa (14.66 ± 0.74 mm). AgNPs from the methanol extract also displayed the highest antioxidant activity, with an IC50 value of 188.00 ± 2.67 μg/mL against 2,2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, AgNPs exhibited notable cytotoxic activity against Rhabdomyosarcoma cell line (RD cell) of human muscle cancer cell. The IC50 values calculated from the MTT assay were 26.28 ± 1.58 and 21.49 ± 1.44 μg/mL for AgNPs synthesized from aqueous and methanol extracts, respectively.

CONCLUSION

The methanol extract of V. grandiflorum leaves demonstrates significant potential for synthesizing AgNPs with effective antibacterial, antioxidant, and anticancer actions, making them applicable in various biomedical applications.

Plant-mediated synthesis of silver nanoparticles: unlocking their pharmacological potential-a comprehensive review

In recent times, nanoparticles have experienced a significant upsurge in popularity, primarily owing to their minute size and their remarkable ability to modify physical, chemical, and biological properties. This burgeoning interest can be attributed to the expanding array of biomedical applications where nanoparticles find utility. These nanoparticles, typically ranging in size from 10 to 100 nm, exhibit diverse shapes, such as spherical, discoidal, and cylindrical configurations. These variations are not solely influenced by the manufacturing processes but are also intricately linked to interactions with surrounding stabilizing agents and initiators. Nanoparticles can be synthesized through physical or chemical methods, yet the biological approach emerges as the most sustainable and eco-friendly alternative among the three. Among the various nanoparticle types, silver nanoparticles have emerged as the most encountered and widely utilized due to their exceptional properties. What makes the synthesis of silver nanoparticles even more appealing is the application of plant-derived sources as reducing agents. This approach not only proves to be cost-effective but also significantly reduces the synthesis time. Notably, silver nanoparticles produced through plant-mediated processes have garnered considerable attention in recent years due to their notable medicinal capabilities. This comprehensive review primarily delves into the diverse medicinal attributes of silver nanoparticles synthesized using plant-mediated techniques. Encompassing antimicrobial properties, cytotoxicity, wound healing, larvicidal effects, anti-angiogenesis activity, antioxidant potential, and antiplasmodial activity, the paper extensively covers these multifaceted roles. Additionally, an endeavor is made to provide an elucidated summary of the operational mechanisms underlying the pharmacological actions of silver nanoparticles.

Evaluation of Antibacterial, Antioxidant, Anti-inflammatory and Anticancer Efficacy of Titanium-Doped Graphene Oxide Nanoparticles

INTRODUCTION

The current development of nanoparticles (NPs) with significant antibacterial properties, low cost and low toxicity has made it possible to develop novel techniques for treatments in the medical field. The titanium metal oxide, when combined with a carbonaceous material like graphene, which has excellent absorbing capacity, is efficient in loading drugs and thus helps in drug delivery and also in biomedical applications like anticancer, anti-inflammatory, antioxidant, and antibacterial activities.

MATERIALS AND METHODS

Titanium-doped graphene oxide nanoparticles (Ti/GO-NPs) were processed by the one-pot synthesis method; further characterization was performed by using UV-visible spectroscopy, Fourier transform-infrared spectroscopy (FT-IR), field emission electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDX) analysis and biomedical applications like anticancer, anti-inflammatory, antioxidant and antibacterial activities.

RESULTS

The synthesized end product of Ti/GO-NPs showed a creamy white appearance. Subsequent characterization studies of UV-Vis spectroscopy revealed a peak level of 373 nm at 24 hours and 404 nm after 48 hours. FT-IR analysis exhibited a broad absorption band within the range of 1000-3500 cm-1, which was attributed to various chemical compounds of C-Br, C-I stretching, C=C bending, S=O stretching, O=H stretching, C=C stretching, H bonded and OH stretching to different absorbance wavelength ranges. SEM analysis exhibited quasi-spherical-shaped Ti/GO-NPs with an average particle size of 50- 100 nm and EDX analysis showed the elemental composition of 32.3% titanium 43.9% oxygen and 2.5% carbon. The antibacterial activity showed moderate activity against Staphylococcus aureus and no activity against Pseudomonas aeruginosa, Enterococcus faecalis and E. coli. The antioxidant activity exhibited 88% at 50 µg/mL concentration, the anti-inflammatory activity revealed 80% at 80 µg/mL concentration and the anticancer activity showed 21% at 150 µg/mL concentration.

CONCLUSION

The characterization and biomedical application conclude that a combination of Ti/GO-NPs will be efficient in drug delivery. The study showed moderate antibacterial activity and significant antioxidant, anti-inflammatory and anticancer activities. Considering their physiochemical properties, absorption capacity and mechanism of drug delivery, Ti/GO-NPs can be incorporated into various applications in the medical field.

Attenuation of biofilm and quorum sensing regulated virulence factors of an opportunistic pathogen Pseudomonas aeruginosa by phytofabricated silver nanoparticles

Green-synthesized nanoparticles provide an effective strategy for inhibiting microbial pathogenesis by affecting biofilm formation, quorum sensing (QS), and other surface properties of microorganisms. QS is a density-dependent communication signaling cascade that regulates biofilm formation and other pathogenic factors of Pseudomonas aeruginosa. In this context, the effect of phytofabricated silver nanoparticles (CC-AgNPs) synthesized using Cuphea carthagenensis extract on biofilm, QS, and QS-dependent virulence factors of P. aeruginosa were evaluated in this study. CC-AgNPs demonstrated significant attenuation of biofilm, QS, and QS-dependent virulence factors at sub-MICs. A significant inhibition of 88.39 ± 4.32 %, 79.64 ± 3.31 %, 73.07 ± 3.0 %, and 61.67 ± 1.5 % of biofilm formation, quorum sensing, pyocyanin, and LasB elastase, respectively was reported in the study at 20 μg/mL. The study also demonstrated a significant reduction of LasA Staphylolytic activity and 91.37 ± 1.05 % exoprotease production in comparison to untreated control. The lower concentrations of CC-AgNPs also demonstrated significant attenuation of biofilm and other virulence factors suggesting the strong potency of NPs against P. aeruginosa. XTT analysis reported the effect of CC-AgNPs on sessile cells of P. aeruginosa without impacting growth of planktonic cells at sub-MICs. Cell-proliferation study in human cell lines (HEK 293 and Caco-2 cells) demonstrated the safe nature of CC-AgNPs at tested concentrations. This study is novel in a way that environmentally friendly CC-AgNPs were used to inhibit QS at sub-MICs without killing the tested strains, therefore, could be developed as an anti-virulent drug to overcome biofilm and antimicrobial resistance problems.

Bactericidal and Antioxidant Potential of Moringa oleifera Capped Silver Nanoparticles under Varied Conditions

Microbial infections have consistently been identified as one of the major threats to global health. In this regard, the current study was designed to synthesize and evaluate the antibacterial activity of Mo‐AgNPs at various concentrations (2, 4, and 8 mg/mL), temperatures (4 °C, 25 °C, 37 °C, and 85 °C) and pH (4, 7, and 11) against Gram‐negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Aeromonas veronii) and Gram‐positive bacteria (Staphylococcus aureus, Bacillus subtilis) by the well diffusion method as well as antioxidant potential using DPPH assay at 2 mg/mL and 4 mg/mL. Fabrication of Mo‐AgNPs was authenticated by UV–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and X‐ray diffraction (XRD). Mo‐AgNPs produced a significant zone of growth inhibition (21.0±0.3 mm) against B. subtilis at 8 mg/mL. At 25 °C, a significant zone of growth inhibition (21.0±0.8 mm) was measured against E. coli. Similarly, at pH 4, Mo‐AgNPs showed significantly highest growth inhibition zones of 12.0±7.5 mm, 12.0±6.3 mm, and 12.0±9.8 mm against P. aeruginosa, K. pneumoniae, and A. veronii, respectively. The present study results indicated that Mo‐AgNPs are stable under varied conditions. Significant free radical scavenging activity (82±0.5 %) of Mo‐AgNPs at 4 mg/mL was observed, which revealed the antioxidant potential of the Mo‐AgNPs.

Visible light-driven photocatalysts, quantum chemical calculations, ADMET-SAR parameters, and DNA binding studies of nickel complex of sulfadiazine

A 3D-supramolecular nickel integrated Ni-SDZ complex was synthesized using sodium salt of sulfadiazine as the ligand and nickel(II) acetate as the metal salt using a condensation process and slow evaporation approach to growing the single crystal. The metal complex was characterized for its composition, functional groups, surface morphology as well as complex 3D structure, by resorting to various analytical techniques. The interacting surface and stability as well as reactivity of the complex were carried out using the DFT platform. From ADMET parameters, human Intestinal Absorbance data revealed that the compound has the potential to be well absorbed, and also Ni-SDZ complex cannot cross the blood-brain barrier (BBB). Additionally, the complex's DNA binding affinity and in-vivo and in-vitro cytotoxic studies were explored utilizing UV-Vis absorbance titration, viscosity measurements, and S. pombe cells and brine shrimp lethality tests. In visible light radiation, the Ni-SDZ complex displayed exceptional photo-degradation characteristics of approximately 70.19% within 70 min against methylene blue (MB).

Characterization and Evaluation of Silver Concentrations in Hydroxyapatite Powders

The goal of this study is to evaluate the influence of the concentration of silver on the structural and antimicrobial in vitro properties of silver-doped hydroxyapatite powders obtained using the precipitation method. Different concentrations of silver were evaluated to assess the antimicrobial properties. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), and dispersive energy spectroscopy (EDS) were used to characterize the powders. XRD and FTIR showed that the hydroxyapatite structure is not affected by the incorporation of silver; on the other hand, EDS showed the presence of silver in the powders. Antibacterial studies showed the efficiency of hydroxyapatite powders in inhibiting bacterial growth as silver concentration increases. According to the results, silver-doped hydroxyapatite powders are suggested for use in the prevention and treatment of infections in bone and dental tissues.

The Antibacterial Effectiveness of Citrullus lanatus-Mediated Stannous Nanoparticles on Streptococcus mutans

Introduction Dental caries is a prevalent oral health issue caused by the colonization of Streptococcus mutans in the oral cavity. Citrullus lanatus, commonly known as watermelon, is rich in bioactive compounds that possess antibacterial potential. In this study, we aimed to synthesize stannous chloride (SnCl2) nanoparticles (NPs) mediated by Citrullus lanatus extract and investigate their antibacterial effectiveness against Streptococcus mutans. Materials and method Stannous nanoparticles (SnNPs) synthesized by the green method were achieved by using the watermelon extract. Dilute stannous chloride solution was obtained by adding 0.45 g of stannous (Sn) chloride (Cl) powder to 60 mL of water, which was subjected to an orbital shaker with the watermelon extract. The nanoparticles obtained were subjected to characterization using antimicrobial testing, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray (EDAX) analysis, and scanning electron microscopy (SEM). Agar well diffusion method was used against specific strains of S. aureus, S. mutans, and Escherichia coli. Results The novel nanoparticles demonstrated promising antibacterial activity against S. mutans providing 10 mm of inhibitory action. Conclusion Due to its abundance of naturally occurring bioactive chemicals and improved efficacy against S. mutans, watermelon extract can be utilized to create stannous nanoparticles as opposed to the use of toxic chemicals. They can also be employed as oral administration systems.

Antibacterial and Antibiofilm Activity of Chemically and Biologically Synthesized Silver Nanoparticles

Bacterial biofilms are a significant problem in the food industry, as they are difficult to eradicate and represent a threat to consumer health. Currently, nanoparticles as an alternative to traditional chemical disinfectants have garnered much attention due to their broad-spectrum antibacterial activity and low toxicity. In this study, silver nanoparticles (AgNPs) were synthesized by a biological method using a Jacaranda mimosifolia flower aqueous extract and by a chemical method, and the factors affecting both syntheses were optimized. The nanoparticles were characterized by Ultraviolet-visible (UV-Vis) spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), Dynamic light scattering (DLS), X-ray diffraction (XRD), and Transmission electron microscopy (TEM) with a spherical and uniform shape. The antibacterial and antibiofilm formation activity was carried out on bacterial species of Pseudomonas aeruginosa and Staphylococcus aureus with the capacity to form biofilm. The minimum inhibitory concentration was 117.5 μg/mL for the chemical and 5.3 μg/mL for the biological nanoparticles. Both types of nanoparticles showed antibiofilm activity in the qualitative Congo red test and in the quantitative microplate test. Antibiofilm activity tests on fresh lettuce showed that biological nanoparticles decreased the population of S. aureus and P. aeruginosa by 0.63 and 2.38 logarithms, respectively, while chemical nanoparticles had little microbial reduction. In conclusion, the biologically synthesized nanoparticles showed greater antibiofilm activity. Therefore, these results suggest their potential application in the formulation of sanitizing products for the food and healthcare industries.

Green synthesis of silver nanoparticles mediated Diospyros kaki L. (Persimmon): determination of chemical composition and evaluation of their antimicrobials and anticancer activities

The eco-friendly synthesis of metallic nanoparticles (MNPs) using biological materials is an encouraging and innovativeness approach to nanotechnology. Among other synthesizing methods, biological methods are chosen because of their high efficiency and purity in many aspects. In this work, using the aqueous extract obtained from the green leaves of the D. kaki L. (DK); silver nanoparticles were synthesized in a short time and simply with an eco-friendly approach. The properties of the synthesized silver nanoparticles (AgNPs) were characterized using various techniques and measurements. In the characterization data of AgNPs, Maximum absorbance at 453.34 nm wavelengths, the average size distribution of 27.12 nm, the surface charge of -22.4 mV, and spherical appearance were observed. LC-ESI-MS/MS analysis was used to assess the compound composition of D. kaki leaf extract. The chemical profiling of the crude extract of D. kaki leaves revealed the presence of a variety of phytochemicals, predominantly phenolics, resulting in the identification of five major high-feature compounds: two major phenolic acids (Chlorogenic acid and Cynarin), and tree flavonol glucosides (hyperoside, quercetin-3-glucoside, and quercetin-3- D-xyloside). The components with the highest concentrations were cynarin, chlorogenic acid, quercetin-3- D-xyloside, hyperoside, and quercetin-3-glucoside, respectively. Antimicrobial results were determined by a MIC assay. The biosynthesized AgNPs exhibited strong antibacterial activity against the human and food pathogen Gram (+ and -) bacteria and good antifungal activity against pathogenic yeast. It was determined that 0.03-0.050 μg/mL concentrations ranges of DK-AgNPs were growth suppressive concentrations on all pathogen microorganisms. The MTT technique was used to study the cytotoxic effects of produced AgNPs on cancer cell lines (Glioblastoma (U118), Human Colorectal Adenocarcinoma (Caco-2), Human Ovarian Sarcoma (Skov-3) cancer cell lines, and Human Dermal Fibroblast (HDF) healthy cell line). It has been observed that they have a suppressive effect on the proliferation of cancerous cell lines. After 48 h of treatment with Ag-NPs, the DK-AgNPs were found to be extremely cytotoxic to the CaCo-2 cell line, inhibiting cell viability by up to 59.49% at a concentration of 50 g mL^-1. It was found that the viability was inversely related to the DK-AgNP concentration. The biosynthesized AgNPs had dose-dependent anticancer efficacy. Because of the high concentration of bioactive chemicals in Diospyros kaki, it may be employed as a biological resource in medicinal applications. DK-AgNPs were shown to be an effective antibacterial agent as well as a prospective anticancer agent. The results provide a potential approach for the biogenic production of DK-AgNPs utilizing D. kaki aqueous leaf extract.

Green synthesis, characterization, and biological evaluation of gold and silver nanoparticles using Mentha spicata essential oil

Green synthesis of bioactive nanoparticles (NPs) is getting more attractive in various fields of science including the food industry. This study investigates the green synthesizing and characterization of gold NPs (AuNPs) and silver NPs (AgNPs) produced using Mentha spicata L. (M. spicata) essential oil as well as their antibacterial, antioxidant, and in vitro cytotoxic effects. The essential oil was mixed with both Chloroauric acid (HAuCl₄) and aqueous silver nitrate (AgNO₃) solutions separately and incubated at room temperature for 24 h. The chemical composition of the essential oil was identified by gas chromatography coupled with a mass spectrometer detector (GC-MS). Au and Ag nanoparticles were characterized using UV-Vis spectroscopy, transmission electron microscopy, scanning electron microscopy, dynamic light scattering (DLS), X-ray diffraction (XRD) and Fourier transform infrared (FTIR). The cytotoxicity of both types of nanoparticles was evaluated using MTT assay on cancerous HEPG-2cell line by exposing them to various concentrations of both NPs for 24 h. The antimicrobial effect was evaluated by the well-diffusion technique. The antioxidant effect was determined by DPPH and ABTS tests. According to the results of GC-MS analysis, 18 components were identified, including carvone (78.76%) and limonene (11.50%). UV-visible spectroscopy showed a strong absorption peak of 563 nm and 485 nm, indicating the formation of Au NPs and Ag NPs, respectively. TEM and DLS demonstrated that AuNPs and AgNPs were predominantly spherical shaped with average sizes of 19.61 nm and 24 nm, respectively. FTIR analysis showed that biologically active compounds such as monoterpenes could assist in the formation and stabilization of both types of NPs. Additionally, XRD provided more accurate results, revealing a nano-metal structure. Silver nanoparticles exhibited better antimicrobial activity against the bacteria than AuNPs. Zones of inhibition ranging 9.0-16.0 mm were recorded for the AgNPs, while zones of 8.0-10.33 mm were observed AuNPs. In the ABTS assay, the AuNPs and AgNPs showed a dose-dependent activity and synthesized nanoparticles exhibited higher antioxidant activity than MSEO in both assays. Mentha spicata essential oil can be successfully used for the green production of Au NPs and Ag NPs. Both green synthesized NPs show antibacterial, antioxidant, and in vitro cytotoxic activity.

Green Biofabrication of Silver Nanoparticles of Potential Synergistic Activity with Antibacterial and Antifungal Agents against Some Nosocomial Pathogens

Nosocomial bacterial and fungal infections are one of the main causes of high morbidity and mortality worldwide, owing to the high prevalence of multidrug-resistant microbial strains. Hence, the study aims to synthesize, characterize, and investigate the antifungal and antibacterial activity of silver nanoparticles (AgNPs) fabricated using Camellia sinensis leaves against nosocomial pathogens. The biogenic AgNPs revealed a small particle diameter of 35.761 ± 3.18 nm based on transmission electron microscope (TEM) graphs and a negative surface charge of −14.1 mV, revealing the repulsive forces between nanoparticles, which in turn indicated their colloidal stability. The disk diffusion assay confirmed that Escherichia coli was the most susceptible bacterial strain to the biogenic AgNPs (200 g/disk), while the lowest sensitive strain was found to be the Acinetobacter baumannii strain with relative inhibition zones of 36.14 ± 0.67 and 21.04 ± 0.19 mm, respectively. On the other hand, the biogenic AgNPs (200 µg/disk) exposed antifungal efficacy against Candida albicans strain with a relative inhibition zone of 18.16 ± 0.14 mm in diameter. The biogenic AgNPs exposed synergistic activity with both tigecycline and clotrimazole against A. baumannii and C. albicans, respectively. In conclusion, the biogenic AgNPs demonstrated distinct physicochemical properties and potential synergistic bioactivity with tigecycline, linezolid, and clotrimazole against gram-negative, gram-positive, and fungal strains, respectively. This is paving the way for the development of effective antimicrobial combinations for the effective management of nosocomial pathogens in intensive care units (ICUs) and health care settings.

Molecular docking analysis of oxazole compounds with the heme-binding protein from Porphyromonas gingivalis

Porphyromonas gingivalis, a peripathogen, has several methods to impede or modify the protective mechanisms of the teeth. Targeting the inhibition of the heme protein will prevent the organism from multiplying and inhibit the virulence mechanism. The literature derived oxazole compounds (1-5) were docked against the protein's active site, and the results show that the selected oxazole derivatives exhibit better interaction compared to clinically proven drugs.

Development of Decellularized Fish Skin Scaffold Decorated with Biosynthesized Silver Nanoparticles for Accelerated Burn Wound Healing

In this study, decellularized fish skin (DFS) scaffold decorated with silver nanoparticles was prepared for accelerating burn wound healing. The silver nanoparticles (AgNPs) synthesized by the green and facile method using Aloe vera leaf at different incubating times were characterized by using X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) Spectroscopy, and Ultraviolet-Visible Spectroscopy (UV-Vis spectroscopy). The different characterizations confirmed that the sizes of AgNPs prepared by incubating for 6 hours and 12 hours were 29.1 nm and 35.2 nm, respectively. After that, the different concentrations of the smallest AgNPs were used to dope the DFS scaffold to determine the cell viability. Additionally, an agar well diffusion method was used to screen for antimicrobial activity. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were used to correlate the concentration of AgNPs with its bactericidal effect which was seen from 50 μg/ml. Then, the toxicity with human cells was investigated using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay with no significant cell viability from the concentration of 50 μg/ml to 200 μg/ml compared to the cocultured and commercial treatments.

Molecular docking analysis of Indole based diaza-sulphonamides with JAK-3 protein

JAK-3 gene is a part of an important signalling pathway in oral cancer. Therefore, it is of interest to evaluate the inhibitory properties of new indole based diaza-sulphonamides compounds against JAK3 gene. Molecular docking analysis showed that among the selected compounds (1-9), the compounds 1-4 turned out to be the most potentially capable ones to be used as ant-cancer drugs. Also, they are proved to be non-toxic.

Green Synthesis and Antimicrobial Study on Functionalized Chestnut-Shell-Extract Ag Nanoparticles

The chestnut shell is usually discarded as agricultural waste and the random deposition of it can cause environmental problems. In this study, monodisperse crystalline Ag nanoparticles (AgNPs) were synthesized by a hydrothermal approach, in which the chestnut shell extract served as both reducing agent and stabilizer. The synthesized Ag nanoparticles were characterized by ultraviolet-visible (UV) spectrophotometry, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) measurements. The TEM, XRD and XPS results revealed that the synthesized product was spherical Ag nanoparticles with a face-centered cubic crystal structure. The antimicrobial activity test indicated that the Ag nanoparticles modified by the chestnut shell extract had an obvious inhibitory effect on Escherichia coli, Staphylococcus aureus and Candida albicans. The measured MIC and MBC of functionalized chestnut-shell-extract AgNPs against E. coli, S. aureus and C. albicans is relatively low, which indicated that the present functionalized chestnut-shell-extract AgNPs are an efficient antimicrobial agent.

Molecular docking analysis of thiazo inhibitors with the virulent factor cystalysin from Treponema denticola

Treponema Denticola has a virulent protein called cystalysin, which causes periodontitis. Therefore, it is of interest to design efficient drug that may have fewer side effects than the present clinical drugs, considering most of them are multidrug resistant. The molecular docking analysis show that the selected thiazo derivatives (1-6) show better binding energies and amino acid interactions compared to the clinically proven drugs proving to be potential inhibitors against the protein.

Molecular docking analysis of protein filamin-A with thioazo compounds

It is of interest to document the molecular docking analysis of protein Filamin-A with thioazo compounds. The compounds 1, 3, 5, and 6 showed best molecular docking interaction as compared to the drug doxorubicin. Among the selected ligands (1-6), compound 3 shows better interaction score than doxorubicin and follows Lipinski's rule of five. Hence, it could be considered as a potential lead molecule for inhibiting protein filamin A in the treatment of oral cancer.

Molecular docking analysis of the oral tumor target JAK STAT 3 with oxo-azo compounds

It is of interest to identify the JAK STAT 3 signaling inhibitors to abrogate tumorigenesis in oral cancer. Hence, molecular docking was performed with known oxazole compounds (1-5) and the 3D crystal structure of JAK-1 protein from Homo sapiens (PDB ID: 3EYG). The results show that the oxo-azo derivatives showed better interactions within the binding site of proteins. We report that compounds 1, 4 and 5 optimal binding features with JAK STAT 3.

Evaluating the effects of zeolitic imidazolate framework and Eremostachys binalodensis extract on Candida albicans and Streptococcus mutans biofilms

Biofilms represent longstanding challenges to oral health care. Candida albicans and Streptococcus mutans are the common pathogens forming biofilms. The growing resistance to and the adverse effects of antibiotics limit their usage and raise the need for novel approaches. Herbal extracts have emerged as efficient choices with lower costs and fewer adverse effects. Metal frameworks have captivated interest due to their high surface area, special biocompatibility, and non-toxicity. The effects of zeolitic imidazolate frameworks/layered double hydroxide (ZIF/LDH) on fungal infections and the potential effects of Eremostachys binalodensis on bacteria encouraged the researchers to evaluate the effect of ZIF/LDH, E. binalodensis, and their combination on C. albicans and S. mutans biofilms. ZIF/LDH nanocomposite was synthesized and characterized using scanning electron microscopy, Fourier transform infrared spectra, and X-ray diffraction to assess morphology and chemical structure. Methanol extracts of the areal parts of E. binalodensis were obtained by Soxhlet extraction. The microdilution tests and biofilm crystal violet staining were applied. Concentrations of 2.048 and 4.096 mg/ml E. binalodensis prevented C. albicans and S. mutans biofilm formation. The combination of ZIF/LDH + E. binalodensis prevented C. albicans and S. mutans biofilm formation. This research suggests the use of E. binalodensis-loaded ZIF/LDH nanocomposites for removing biofilms.

Eco-Friendly Green Synthesis of Rubropunctatin Functionalized Silver Nanoparticles and Evaluation of Antibacterial Activity

In order to solve the problems of rubropunctatin insoluble in water and its low bioavailability, and explore the synthesis method of green silver nanoparticles, rubropunctatin was used as reducing agent and blocking agent, rubropunctatin-functionalized silver nanoparticles (R-AgNPs) were successfully synthesized. The distinctive absorption peak at 410 nm confirmed the formation of R-AgNPs. Zeta potential measurement showed excellent stability of R-AgNPs with negative values of -29.81 ± 0.37 mV. The results of TEM and XRD showed that the prepared R-AgNPs were round, well dispersed and crystallized with average particle size of 13.54 ± 0.42 nm. FT-IR and XPS studies show that functional groups are involved in R-AgNPs synthesis. The antibacterial activity of R-AgNPs was compared with commercial silver nanoparticles (AgNPs) by microdilution method. The results showed that R-AgNPs (MIC 7.81 μg/mL) has stronger antibacterial activity than commercial AgNPs. The bacteria morphology was observed by the live and dead (SYTO 9/PI) staining assay and SEM showed that the antibacterial effect of R-AgNPs was caused by the destruction of the bacterial cell membrane. Cytotoxicity of rubropunctatin-functionalized silver nanoparticles and commercial silver nanoparticles on mouse fibroblast 3T3 cells was assessed by CCK-8 assay. The results showed that the toxicity of rubropunctatin-functionalized silver nanoparticles to 3T3 cells was lower than that of commercial silver nanoparticles. In summary, synthesis of silver nanoparticles using rubropunctatin is a green synthesis method, and R-AgNPs is a potential antibacterial agent.

Synergistic and antibiofilm potential of Curcuma aromatica derived silver nanoparticles in combination with antibiotics against multidrug-resistant pathogens

Hospital acquired infections caused due to ESKAPE pathogens pose a challenge for treatment due to their growing antimicrobial resistance. Curcuma aromatica (CA) is traditionally known for its antibacterial, wound healing and anti-inflammatory properties. The present study highlights the biogenic synthesis of silver nanoparticles (CAAgNPs) capped and stabilized by the compounds from CA rhizome extract, also further demonstrating their antibacterial, antibiofilm and synergistic effects against multidrug-resistant (MDR) pathogens. CAAgNPs were synthesized using aqueous rhizome extract of CA (5 mg/ml) and AgNO3 (0.8 mM) incubated at 60°C up to 144 h. UV-vis spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) revealed CAAgNPs with characteristic peak at 430 nm, 13 ± 5 nm size of spherical shape, showing presence of silver and crystalline nature, respectively. Dynamic light scattering (DLS) and zeta potential confirmed their monodispersed nature with average diameter of 77.88 ± 48.60 nm and stability. Fourier transform infrared spectroscopic (FTIR) analysis demonstrated the presence of phenolic -OH and carbonyl groups possibly involved in the reduction and stabilization of CAAgNPs. The minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs) and minimum biofilm inhibitory concentrations (MBICs) of CAAgNPs against Pseudomonas aeruginosa, NCIM 5029 and PAW1, and, Staphylococcus aureus, NCIM 5021 and S8 were in range from 8 to 128 μg/ml. Almost 50% disruption of pre-formed biofilms at concentrations 8-1,024 μg/ml was observed. Fluorescence microscopy and FESEM analysis confirmed cell death and disruption of pre-formed biofilms of P. aeruginosa PAW1 and S. aureus S8. Checkerboard assay demonstrated the synergistic effect of CAAgNPs (0.125-4 μg/ml) in combination with various antibiotics (0.063-1,024 μg/ml) against planktonic and biofilm forms of P. aeruginosa PAW1. The study confirms the antibacterial and antibiofilm activity of CAAgNPs alone and in combination with antibiotics against MDR pathogens, thus, reducing the dose as well as toxicity of both. CAAgNPs have the potential to be used in wound dressings and ointments, and to improve the performances of medical devices and surgical implants. In vivo toxicity of CAAgNPs however needs to be tested further using mice models.