Graphene/nickel oxide nanocomposites against isolated ESBL producing bacteria and A549 cancer cells

Targeted Nanotherapy by Vinblastine-Loaded Chitosan-Coated PLA Nanoparticles to Improve the Chemotherapy via Reactive Oxygen Species to Hamper Hepatocellular Carcinoma

Liver cancer is a prevalent and significant cause of death in humans. The use of novel biodegradable materials for various biomedical applications is being recently recommended as complementary as well as alternative solution for traditional chemotherapy. This study focuses on the synthesis of biodegradable nanocarriers [chitosan-coated poly(lactic acid) NPs (Cht-PLA NPs)] for the delivery of an anticancer drug vinblastine (Vbx) and to evaluate its therapeutic potential in human hepatocellular carcinoma (HepG2) cells. The Cht-PLA NPs were synthesized using the nanoprecipitation method and characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering, and zeta potential techniques. The results showed that the nanoparticle sizes are in the range of 100-200 nm with positive surface charge. The release profile of the synthesized nanoformulation showed controlled release of the Vbx drug for 72 h. The anticancer efficacy of the synthesized nanoformulation was assessed on the HepG2 cell lines. The in vitro cytotoxicity study revealed that the Vbx-loaded Cht-PLA NPs showed higher toxicity with an increase in concentration as compared to the Vbx alone. Additionally, an in vitro cellular uptake study revealed higher internalization as compared to the drug alone due to the chitosan coating. Further, the ability to stimulate the reactive oxygen species (ROS) generation and variation in mitochondrial membrane potential at the IC50 concentration of Vbx-loaded Cht-PLA NPs was confirmed by using 2,7-dichlorodihydrofluorescein diacetate and rhodamine 123 dyes, respectively, and were analyzed under fluorescence microscopy. Hence, the results showed that Vbx-loaded Cht-PLA NPs possess high anticancer activity due to its higher cellular toxicity, cellular uptake, increased ROS production, and disruption in mitochondrial membrane potential. All these properties of the synthesized nanoformulation suggest it's potential applications in drug delivery systems, targeting liver cancer.

Organic acid-fractionated lignin silver nanoparticles: Antimicrobial, anticancer, and antioxidant characteristics

Bioactive substances are utilized to treat a variety of diseases. Green lignin-mediated silver nanoparticles (L-Ag-NPs) have significant promise as a building block in the production of bio-renovation materials. The work optimized organic acid extraction to remove lignin from residual fermented hybrid Napier grass byproducts. We subsequently produced L-Ag-NPs. FTIR, XRD, DLS, and STEM characterized the sample. L-Ag-NPs were tested for antioxidant activity with the DPPH, DMPD, FRAP, and ABTS assays, as well as antibacterial activities. Antimicrobial activity was evaluated using four pathogenic bacteria (Klebsiella pneumonia, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli). In contrast, cytotoxicity and ROS production assays were carried out using the HeLa cell line. The findings showed that L-Ag-NPs had high antioxidant efficiency. For each bacteria isolate, the antimicrobial activity showed favorable growth inhibition, with significant variations in L-Ag-NPs. L-Ag-NPs were reported to have an IC50 of 43.61 g/mL in the cytotoxicity test, and a significant increase in ROS generation was seen. In conclusion, L-Ag NPs have an excellent prospect in the pharmaceutical and biomedical industries and can be a dependable and environmentally safe material for their potential use.

Selective Tumor Inhibition Effect of Drug-Free Layered Double Hydroxide-Based Films via Responding to Acidic Microenvironment

Nickel-titanium alloy stents are widely used in the interventional treatment of various malignant tumors, and it is important to develop nickel-titanium alloy stents with selective cancer-inhibiting and antibacterial functions to avoid malignant obstruction caused by tumor invasion and bacterial colonization. In this work, an acid-responsive layered double hydroxide (LDH) film was constructed on the surface of a nickel-titanium alloy by hydrothermal treatment. The release of nickel ions from the film in the acidic tumor microenvironment induces an intracellular oxidative stress response that leads to cell death. In addition, the specific surface area of LDH nanosheets could be further regulated by heat treatment to modulate the release of nickel ions in the acidic microenvironment, allowing the antitumor effect to be further enhanced. This acid-responsive LDH film also shows a good antibacterial effect against S. aureus and E. coli. Besides, the LDH film prepared without the introduction of additional elements maintains low toxicity to normal cells in a normal physiological environment. This work offers some guidance for the design of a practical nickel-titanium alloy stent for the interventional treatment of tumors.

Nanomaterial in controlling biofilms and virulence of microbial pathogens

The escalating threat of antimicrobial resistance (AMR) poses a grave concern to global public health, exacerbated by the alarming shortage of effective antibiotics in the pipeline. Biofilms, intricate populations of bacteria encased in self-produced matrices, pose a significant challenge to treatment, as they enhance resistance to antibiotics and contribute to the persistence of organisms. Amid these challenges, nanotechnology emerges as a promising domain in the fight against biofilms. Nanomaterials, with their unique properties at the nanoscale, offer innovative antibacterial modalities not present in traditional defensive mechanisms. This comprehensive review focuses on the potential of nanotechnology in combating biofilms, focusing on green-synthesized nanoparticles and their associated anti-biofilm potential. The review encompasses various aspects of nanoparticle-mediated biofilm inhibition, including mechanisms of action. The diverse mechanisms of action of green-synthesized nanoparticles offer valuable insights into their potential applications in addressing AMR and improving treatment outcomes, highlighting novel strategies in the ongoing battle against infectious diseases.

Fungus-mediated synthesis of Se-BiO-CuO multimetallic nanoparticles as a potential alternative antimicrobial against ESBL-producing Escherichia coli of veterinary origin

Bacterial infections emerge as a significant contributor to mortality and morbidity worldwide. Emerging extended-spectrum β-lactamase (ESBL) Escherichia coli strains provide a greater risk of bacteremia and mortality, are increasingly resistant to antibiotics, and are a major producer of ESBLs. E. coli bacteremia-linked mastitis is one of the most common bacterial diseases in animals, which can affect the quality of the milk and damage organ functions. There is an elevated menace of treatment failure and recurrence of E. coli bacteremia necessitating the adoption of rigorous alternative treatment approaches. In this study, Se-Boil-CuO multimetallic nanoparticles (MMNPs) were synthesized as an alternate treatment from Talaromyces haitouensis extract, and their efficiency in treating ESBL E. coli was confirmed using standard antimicrobial assays. Scanning electron microscopy, UV-visible spectroscopy, and dynamic light scattering were used to validate and characterize the mycosynthesized Se-BiO-CuO MMNPs. UV-visible spectra of Se-BiO-CuO MMNPs showed absorption peak bands at 570, 376, and 290 nm, respectively. The average diameters of the amorphous-shaped Se-BiO-CuO MMNPs synthesized by T. haitouensis extract were approximately 66-80 nm, respectively. Se-BiO-CuO MMNPs (100 μg/mL) showed a maximal inhibition zone of 18.33 ± 0.57 mm against E. coli. Se-BiO-CuO MMNPs also exhibited a deleterious impact on E. coli killing kinetics, biofilm formation, swimming motility, efflux of cellular components, and membrane integrity. The hemolysis assay also confirms the biocompatibility of Se-BiO-CuO MMNPs at the minimum inhibitory concentration (MIC) range. Our findings suggest that Se-BiO-CuO MMNPs may serve as a potential substitute for ESBL E. coli bacteremia.

Apoptosis induction capability of silver nanoparticles capped with Acorus calamus L. and Dalbergia sissoo Roxb. Ex DC. against lung carcinoma cells

Silver nanoparticles (AgNPs) were prepared using a one-step reduction of silver nitrate (AgNO3) with sodium borohydride (NaBH4) in the presence of polyvinylpyrrolidone (PVP) as a capping agent. Plant extracts from D. sissoo (DS) and A. calamus L. (AC) leaves were incorporated during the synthesis process. The crystalline nature of the AgNPs was confirmed through X-ray diffraction (XRD), confirming the face-centered cubic structure, with a lattice constant of 4.08 Å and a crystallite size of 18 nm. Field Emission Gun Transmission Electron Microscopy (FEG-TEM) revealed spherical AgNPs (10-20 nm) with evident PVP adsorption, leading to size changes and agglomeration. UV-Vis spectra showed a surface plasmon resonance (SPR) band at 417 nm for AgNPs and a redshift to 420 nm for PVP-coated AgNPs, indicating successful synthesis. Fourier Transform Infrared Spectroscopy (FTIR) identified functional groups and drug-loaded samples exhibited characteristic peaks, confirming effective drug loading. The anti-cancer potential of synthesized NPs was assessed by MTT assay in human adenocarcinoma lung cancer (A549) and lung normal cells (WI-38) cells. IC50 values for all three NPs (AgPVP NPs, DS@AgPVP NPs, and AC@AgPVP NPs) were 41.60 ± 2.35, 14.25 ± 1.85, and 21.75 ± 0.498 μg/ml on A549 cells, and 420.69 ± 2.87, 408.20 ± 3.41, and 391.80 ± 1.55 μg/ml respectively. Furthermore, the NPs generated Reactive Oxygen Species (ROS) and altered the mitochondrial membrane potential (MMP). Differential staining techniques were used to investigate the apoptosis-inducing properties of the three synthesized NPs. The colony formation assay indicated that nanoparticle therapy prevented cancer cell invasion. Finally, Real-Time PCR (RT-PCR) analysis predicted the expression pattern of many apoptosis-related genes (Caspase 3, 9, and 8).

Respiratory Toxicology of Graphene-Based Nanomaterials: A Review

Graphene-based nanomaterials (GBNs) consist of a single or few layers of graphene sheets or modified graphene including pristine graphene, graphene nanosheets (GNS), graphene oxide (GO), reduced graphene oxide (rGO), as well as graphene modified with various functional groups or chemicals (e.g., hydroxyl, carboxyl, and polyethylene glycol), which are frequently used in industrial and biomedical applications owing to their exceptional physicochemical properties. Given the widespread production and extensive application of GBNs, they can be disseminated in a wide range of environmental mediums, such as air, water, food, and soil. GBNs can enter the human body through various routes such as inhalation, ingestion, dermal penetration, injection, and implantation in biomedical applications, and the majority of GBNs tend to accumulate in the respiratory system. GBNs inhaled and substantially deposited in the human respiratory tract may impair lung defenses and clearance, resulting in the formation of granulomas and pulmonary fibrosis. However, the specific toxicity of the respiratory system caused by different GBNs, their influencing factors, and the underlying mechanisms remain relatively scarce. This review summarizes recent advances in the exposure, metabolism, toxicity and potential mechanisms, current limitations, and future perspectives of various GBNs in the respiratory system.

Seven lower toxicity celastrol derivatives by biotransformation of Pestalotiopsis sp. LGT-1

Biotransformation of toxic components by plant endophytes has become an effective method to reduce the toxicity of target compounds and discover lead compounds. In this context, an endophytic fungus, Pestalotiopsis sp. LGT-1, from Tripterygium wilfordii Hook F. (TwHF), was used to reduce the toxicity of celastrol which is also produced by TwHF and is considered an attractive molecule with a variety of biological activities. Seven celastrol derivatives (1-7) were isolated from the coculture fermentation broth of LGT-1 and celastrol. Their structures were elucidated by spectroscopic data analysis including 1D and 2D NMR, as well as HRESIMS. Their absolute configurations were determined by analysis of NOESY, ECD data and NMR calculations. In cell proliferation experiments, the toxicity of seven compounds was 10.11- to 1.24-fold lower in normal cells than the prototype compound celastrol. These derivatives serve as potential candidates for future pharmaceutical applications.

Extracellular biosynthesis, OVAT/statistical optimization, and characterization of silver nanoparticles (AgNPs) using Leclercia adecarboxylata THHM and its antimicrobial activity

BACKGROUND

The biosynthesis of silver nanoparticles (AgNPs) is an area of interest for researchers due to its eco-friendly approach. The use of biological approaches provides a clean and promising alternative process for the synthesis of AgNPs. We used for the first time the supernatant of Leclercia adecarboxylata THHM under optimal conditions to produce AgNPs with an acceptable antimicrobial activity against important clinical pathogens.

RESULTS

In this study, soil bacteria from different locations were isolated and screened for their potential to form AgNPs. The selected isolate, which was found to have the ability to biosynthesize AgNPs, was identified by molecular methods as Leclercia adecarboxylata THHM and its 16S rRNA gene was deposited in GenBank under the accession number OK605882. Different conditions were screened for the maximum production of AgNPs by the selected bacteria. Five independent variables were investigated through optimizations using one variable at a time (OVAT) and the Plackett-Burman experimental design (PBD). The overall optimal parameters for enhancing the biosynthesis of AgNPs using the supernatant of Leclercia adecarboxylata THHM as a novel organism were at an incubation time of 72.0 h, a concentration of 1.5 mM silver nitrate, a temperature of 40.0 °C, a pH of 7.0, and a supernatant concentration of 30% (v/v) under illumination conditions. The biosynthesized AgNPs have been characterized by UV-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR). The biosynthesized AgNPs showed an absorption peak at 423 nm, spherical shape, and an average particle size of 17.43 nm. FTIR shows the bands at 3321.50, 2160.15, and 1636.33 cm^-1 corresponding to the binding vibrations of amine, alkyne nitrile, and primary amine bands, respectively. The biosynthesized AgNPs showed antimicrobial activity against a variety of microbial pathogens of medical importance. Using resazurin-based microtiter dilution, the minimum inhibitory concentration (MIC) values for AgNPs were 500 µg/mL for all microbial pathogens except for Klebsiella pneumoniae ATCC13883, which has a higher MIC value of 1000 µg/mL.

CONCLUSIONS

The obtained data revealed the successful green production of AgNPs using the supernatant of Leclercia adecarboxylata THHM that can be effectively used as an antimicrobial agent against most human pathogenic microbes.

Physical Characterization and Cellular Toxicity Studies of Commercial NiO Nanoparticles

Nickel oxide (NiO) nanoparticles from several manufacturers with different reported sizes and surface coatings were characterized prior to assessing their cellular toxicity. The physical characterization of these particles revealed that sizes often varied from those reported by the supplier, and that particles were heavily agglomerated when dispersed in water, resulting in a smaller surface area and larger hydrodynamic diameter upon dispersion. Cytotoxicity testing of these materials showed differences between samples; however, correlation of these differences with the physical properties of the materials was not conclusive. Generally, particles with higher surface area and smaller hydrodynamic diameter were more cytotoxic. While all samples produced an increase in reactive oxygen species (ROS), there was no correlation between the magnitude of the increase in ROS and the difference in cytotoxicity between different materials.

Hybrid nanoparticles from chitosan and nickel for enhanced biocidal activities

Cs/Ni/NiO hybrid nanomaterials were prepared by using the precipitation method, The HNPs displayed a nanoflake-like structure and showed high biocidal activity against S. aureus and E. coli strains and breast cancer cell lines.

Anti-ESBL derivatives of marine endophytic Streptomyces xiamenensis GRG 5 (KY457709) against ESBLs producing bacteria

The emerging threat of extended spectrum beta lactamases (ESBLs) producing gram negative bacteria still remains an important worldwide concern. Due to insufficient drug choice and treatment failure of existing drugs,...

Facile synthesis of reduced graphene oxide using Acalypha indica and Raphanus sativus extracts and their in vitro cytotoxicity activity against human breast (MCF-7) and lung (A549) cancer cell lines

In the present study, an eco-friendly approach is adapted for the synthesis of reduced graphene oxide (rGO's) by a simple hydrothermal reaction using two plant extracts namely Acalypha indica and Raphanus sativus. After the hydrothermal reaction, GO turns into a black color from brown color, which indicates the successful reduction of graphene oxide. Further, various characterization techniques such as UV-Vis spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction is used to confirm the physicochemical properties of synthesized rGO's. Raman analysis confirms the reduction of GO by noticing an increase in the I_D/I_G ratio significantly. Field emission scanning electron microscopy and transmission electron microscopy clearly show the morphology and crystalline nature of rGO's. FT-IR spectrum confirms that the bioactive molecules of the plant extract (i.e. polyphenols, flavonoids, terpenoids, etc.) playing a key role in the elimination of oxygen groups from the GO surface. Further, the synthesized rGO's are tested for their potential against human lung and breast cancer cell lines. A significant cancer cell inhibition activity is obtained even in the less concentration of rGO's with IC₅₀ values for lung cancer cell lines are 38.46 µg/mL and 26.69 µg/mL for AIrGO and RSrGO, respectively. Similarly, IC₅₀ values for breast cancer cell lines are 35.97 µg/mL and 33.22 µg/mL for AIrGO and RSrGO, respectively.

Nickel carcinogenesis mechanism: cell cycle dysregulation

Nickel (Ni) is a widely distributed metal in the environment and an important pollutant due to its widespread industrial applications. Ni has various toxicity in humans and experimental animals, including carcinogenicity. However, the carcinogenic effects of Ni remain troublesome. Cell cycle dysregulation may be an important carcinogenic mechanism and is also a potential molecular mechanism for Ni complexes anti-cancerous effects. Therefore, we conducted a literature review to summarize the effects of Ni on cell cycle. Up to now, there were three different reports on Ni-induced cell cycle arrest: (i) Ni can induce cell cycle arrest in G0/G1 phase, phosphorylation and degradation of IkappaB kinase-alpha (IKKα)-dependent cyclin D1 and phosphoinositide-3-kinase (PI3K)/serine-threonine kinase (Akt) pathway-mediated down-regulation of expressions of cyclin-dependent kinases 4 (CDK4) play important role in it; (ii) Ni can induce cell cycle arrest in S phase, but the molecular mechanism is not known; (iii) G2/M phase is the target of Ni toxicity, and Ni compounds cause G2/M cell cycle phase arrest by reducing cyclinB1/Cdc2 interaction through the activation of the ataxia telangiectasia mutated (ATM)-p53-p21 and ATM-checkpoint kinase inhibitor 1 (Chk1)/Chk2-cell division cycle 25 (Cdc25) pathways. Revealing the mechanisms of cell cycle dysregulation associated with Ni exposure may help in the prevention and treatment of Ni-related carcinogenicity and toxicology.

Biosynthesized silver nanoparticles using Caulerpa taxifolia against A549 lung cancer cell line through cytotoxicity effect/morphological damage

The Caulerpa taxifolia is excellent marine green algae, which produced enormous bioactive compounds with more biological activities. Also, it is an excellent source for synthesis of Ag NPs with increased bioactivity against various infections. In our study, the marine algae marine algae Caulerpa taxifolia mediated Ag NPs was synthesized effectively. The synthesized Ag NPs was characterized well using UV-spectrometer and X-ray powder diffraction (XRD) and confirmed as synthesized particle was Ag NPs. The available structure of the Ag NPs was morphologically identified by scanning electron microscope (SEM), and exact minimum size, polydispersive spherical shape of the entire Ag NPs structure was confirmed by Transmission electron microscope (TEM). Further, the anti-cancer efficiency of biosynthesized Ag NPs against A549 lung cancer cells was found at 40 µg/mL concentration by cytotoxicity experiment. In addition, the phase contrast images of the result were supported the Ag NPs, which damaged the A549 morphologically clearly. Finally, florescence microscopic images were effectively proved the anti-cancerous effect against A549 lung cancer cells due to the condensed morphology of increased death cells. All the confirmed in-vitro results were clearly stated that the Caulerpa taxifolia mediated Ag NPs has superior anti-cancer agent against A549 lung cancer cells.

Anti-cancer activity of biosynthesized silver nanoparticles using Avicennia marina against A549 lung cancer cells through ROS/mitochondrial damages

The biosynthesized Ag NPs was synthesized by using marine mangrove plant extract Avicennia marina. The synthesized Ag NPs was confirmed by various physiochemical characterization including UV-spectrometer and XRD analysis. In addition, the shape and of the synthesized Ag NPs was morphologically identified by SEM initially and TEM finally. After confirmation, the anti-cancer property of synthesized Ag NPs was confirmed at 50 µg/mL concentration against A549 lung cancer cells by MTT assay. Further, the ability to stimulate the ROS generation and mitochondrial membrane at the IC50 concentration of Ag NPs was confirmed by fluorescence microscopy using DCFH-DA and rhodamine 123 dyes respectively. Finally, the result was concluded that the synthesized Ag NPs has improved anti-cancer activity against A549 cells at lowest concentration.

Anti-bacterial activity of chitosan loaded plant essential oil against multi drug resistant K. pneumoniae

The development of antibiotic resistant in K. pneumoniae is an emerging thread worldwide due to the poor antimicrobial drugs. To overcome this issue, researchers are focused on plant material and their essential oils to fight against multi drug resistant bacteria. In this context, the current study was concentrated in medicinal plant of guva leaves and their essential oils to combat multi drug resistant bacterial infections. The essential oils were successfully screened and confirmed by HRLC-MS analysis. The anti-bacterial ability of the compounds were loaded into the chitosan nanoparticles and proved by FT-IR analysis. In addition, the chitosan loaded essential oils morphology was compared with chitosan alone in SEM analysis and suggested that the material was loaded successfully. Further, the anti-bacterial ability of the chitosan loaded essential oils were primarily confirmed by agar well diffusion method. At the 100 µg/mL of lowest concentration of chitosan loaded essential oils, the multi-drug resistant K. pneumoniae was inhibited with 96% and confirmed by minimum inhibition concentration experiment. Hence, all the experiments were proved that the essential oils were successfully loaded into the chitosan nanoparticles, and it has more anti-bacterial activity against multi-drug resistant K. pneumoniae.

Impact of ROS Generated by Chemical, Physical, and Plasma Techniques on Cancer Attenuation

For the last few decades, while significant improvements have been achieved in cancer therapy, this family of diseases is still considered one of the deadliest threats to human health. Thus, there is an urgent need to find novel strategies in order to tackle this vital medical issue. One of the most pivotal causes of cancer initiation is the presence of reactive oxygen species (ROS) inside the body. Interestingly, on the other hand, high doses of ROS possess the capability to damage malignant cells. Moreover, several important intracellular mechanisms occur during the production of ROS. For these reasons, inducing ROS inside the biological system by utilizing external physical or chemical methods is a promising approach to inhibit the growth of cancer cells. Beside conventional technologies, cold atmospheric plasmas are now receiving much attention as an emerging therapeutic tool for cancer treatment due to their unique biophysical behavior, including the ability to generate considerable amounts of ROS. This review summarizes the important mechanisms of ROS generated by chemical, physical, and plasma approaches. We also emphasize the biological effects and cancer inhibition capabilities of ROS.