Fibroblast Cell Line L929 Research Articles

Synthesis and Characterization of Chitosan/Sericin Composite Blend Membranes Containing Silver Nanoparticles for Effective Antibacterial Applications

AbstractDue to drug‐resistant bacteria, antimicrobial composite materials that will replace antibiotics are among the current research topics. In this study, environmentally‐friendly, low‐cost, easy‐to‐synthesize chitosan/silk sericin/silver nanoparticles (Cht/SS/AgNPs) membranes were obtained for use in antibacterial applications. For material synthesis, firstly, AgNPs were obtained by mixing solution of 2 % sericin (at pH 11)‐10 mM AgNO3 at 100 °C with hydrothermal method and AgNPs formation was confirmed by UV‐Vis measurements. Then, sericin/AgNPs solution was added to chitosan solutions at different ratios and Cht/SS/AgNPs composites were obtained by solvent casting method. The final forms of the membranes were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM)‐energy dispersive X‐ray spectroscopy (EDS), and thermogravimetric analysis (TGA). Water retention capacities and mechanical properties of the membranes were also determined. Finally, antibacterial and biocompatibility properties were evaluated by disc diffusion test method on Escherichia coli and Staphylococcus aureus and MTT on L929 fibroblast cell line, respectively. The obtained membranes had homogeneous appearance, high swelling ratios, good mechanical properties. The composites also showed excellent antibacterial activity, especially on S. aureus and good biocompatibility. In summary, Cht/SS/AgNPs composites can be used as an alternative polymeric antibacterial materials especially as the wound‐dressing materials or functional packaging materials.

Antiviral respiratory masks with plasma-functionalized polypropylene textiles for optimal adsorption of antiviral substance

During the COVID-19 pandemic, face masks were the first line of defense against the spread of infection. However, infectious viruses may remain on medical textiles, potentially serving as an additional source of infection. Due to their chemical inertness, many textiles cannot be enhanced with antiviral functionalities. Through treatment with low-pressure gaseous plasma, we have activated the surface of a medical-grade melt-blown, non-woven polypropylene textile so that it can absorb sodium dodecyl sulfate, an antimicrobial surfactant. Within two hours of contact time, the functionalized textile has been able to inactivate over 7 log10 PFU mL−1 of bacteriophage phi6, a surrogate of enveloped viruses such as SARS-CoV-2, and it has retained its antiviral properties for over 100 days. The functionalized material has not disrupted facial mask filtration efficiency or breathability. In addition, the in vitro biocompatibility testing in accordance with ISO 10993-5 for testing of medical devices has demonstrated that the selected formulation causes no adverse effects on the mouse fibroblast cell line L-929. With the treatment processes that have been completed within seconds, the method seems to have great potential to produce antiviral textiles against future outbreaks.

Optimized production of carboxymethyl cellulose/guar gum based durable hydrogel for in vitro performance assessment

An important objective of researchers is to develop a perfect wound dressing that can effectively treat different kinds of wounds. Natural substances with beneficial qualities, such as plant extracts and biopolymers are an ideal aid for wound care. Hydrogels based on biopolymers offer a lot of promising applications for topical use and are biocompatible, hydrophilic and non-toxic. When employed alone or in conjunction with other active agents, herbal extracts have a great deal of use in the healing of wounds. This study comprises Ruellia tuberosa extract loaded with carboxymethyl cellulose and guar gum hydrogels that have potential anti-bacterial, antioxidant, anti-inflammatory and hemocompatibility. Using mouse fibroblast cells (L929), the MTT (3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) test was conducted to assess the biocompatibility. Furthermore, the scratch wound assay using the L929 fibroblast cell line of mouse was employed to assess the in vitro wound healing potential of the synthesised composite hydrogels.

Design of poly(vinyl pyrrolidone) and poly(ethylene glycol) microneedle arrays for delivering glycosaminoglycan, chondroitin sulfate, and hyaluronic acid

Osteoarthritis (OA) is a prevalent joint disorder characterized by cartilage and bone degradation. Medical therapies like glucosaminoglycan (GAG), chondroitin sulfate (CS), and hyaluronic acid (HA) aim to preserve joint function and reduce inflammation but may cause side effects when administered orally or via injection. Microneedle arrays (MNAs) offer a localized drug delivery method that reduces side effects. Thus, this study aims to demonstrate the feasibility of delivering GAG, CS, and HA using microneedles in vitro. An optimal needle geometry is crucial for the successful application of MNA. To address this, here we employ a multi-objective optimization framework using the non-dominated sorting genetic algorithm II (NSGA-II) to determine the ideal MNA design, focusing on preventing needle failure. Then, a three-step fabrication approach is followed to fabricate the MNAs. First, the master (male) molds are fabricated from poly(methyl methacrylate) using mechanical micromachining based on optimized needle geometry. Second, a micro-molding with Polydimethylsiloxane (PDMS) is used for the fabrication of production (female) molds. In the last step, the MNAs were fabricated by microcasting the hydrogels using the production molds. Light microscopy (LIMI) confirms the accuracy of the MNAs manufactured, and in vitro skin insertion tests demonstrate failure-free needle insertion. Subsequently, we confirmed the biocompatibility of MNAs by evaluating their impact on the L929 fibroblast cell line, human chondrocytes, and osteoblasts.

Ultra‐thin benzalkonium chloride‐doped poly(lactic acid) electrospun mat

AbstractIn this study, poly(lactic acid), poly(ethylene glycol), and benzalkonium chloride with different concentrations (3, 5, 7, and 9%wt.) (PLA/PEG/BCL) composite electrospun mats were produced. PLA is a non‐toxic polymer with high biocompatibility and biodegradability. However, it may be fragile due to its structure. Therefore, in this study, PEG was used as a plasticizer to improve the structural properties of PLA and it was aimed at providing antibacterial properties by adding BCL salt. Its use as an antibacterial composite nanomaterial effective against Gram‐positive Staphylococcus aureus (S. aureus) and Gram‐negative Escherichia coli (E. coli) bacterial cultures and as a dermal wound dressing material has been examined in two different areas. The addition of BCL salt reduced the bead formation in PLA/PEG nanofibers and increased the homogeneity of fiber dispersion. 9% BCL‐doped composite nanofiber was obtained as the smoothest and most homogeneous surface. This mat was reported to have the highest ductility. The low Tm of pure BCL salt enabled the Tg temperature of PLA/PEG/BCL composite nanofibers to be observed. It was observed that as the BCL salt ratio increased, the T5 and T10 temperatures of the nanofibers decreased and then increased. BCL‐doped mats exhibited liquid absorption behavior in the range of 497%–708%. PLA/PEG/BCL composite nanofibers showed high toxicity to the L929 fibroblast cell line. So, it has been reported that it cannot be used as a dermal wound dressing. PLA/PEG/BCL composite nanomaterials were reported to have 99.99% antibacterial activity against E. coli and S. aureus. It was suggested that it could be used in antibacterial coating applications by taking into account modern nanocoating technology.Highlights Poly(lactic acid), poly(ethylene glycol), and benzalkonium chloride (PLA/PEG/BCL) composite electrospun mats were produced. The addition of BCL salt reduced the bead formation in PLA/PEG nanofibers and increased the homogeneity of fiber dispersion. 9% BCL‐doped composite nanofiber was obtained as the smoothest and most homogeneous surface. PLA/PEG/BCL composite nanofibers showed high toxicity to the L929 fibroblast cell line. PLA/PEG/BCL composite nanomaterials were reported to have 99.99% antibacterial activity against E. coli and S. aureus.

Exploring the anticancer potential of novel chalcone derivatives: Synthesis, characterization, computational analysis, and biological evaluation against breast cancer

This study presents a detailed synthesis and in-depth structural analysis of chalcone compounds with putative anticancer activity. The synthesis procedure for (2E)-1-(2,4-dichlorophenyl)-3-(4-methylphenyl) prop‑2-en-1-one (MLDCL), (2E)-1-(4-fluorophenyl)-3-(4-methylphenyl) prop‑2-en-1-one(MLFC) and (2E)-3-(4-methylphenyl)-1-(4-nitrophenyl) prop‑2-en-1-one (MLNC) involves Claisen-Schmidt condensation reaction. Modern analytical methods like FT-IR and H1 NMR spectroscopy were performed for structural characterization and accurate determination of chalcone compounds in the study. Using a UV–Vis-NIR spectrometer, the linear absorption spectra of three crystals were determined. The optical band gap (Eg) value of these chalcones is acquired from the tauc's plot of (αhv)2/3 against (hv). The in silico molecular docking with protein 3EQM provided valuable insights into potential interactions with the created compounds, yielding docking scores ranging from -8.8 to -7.8. Specific amino acid residues, such as ALA438, ALA306, and ILE133, were implicated in these interactions. The top-ranked compound MLNC (TOP1) from docking was further deemed for molecular dynamics studies, MTT assay, apoptosis, and cell cycle studies. The structural dynamics and stability of protein complexes 3EQM-APO, 3EQM-ASD (standard), and 3EQM-TOP1 were assessed over a 300 ns simulation period. Molecular dynamics studies showed that the complex was stable for a complete 300 ns. MTT assay was performed on triple-negative breast cancer cell line MDMAB-231 and normal fibroblast L929 cell line. An apoptosis and cell cycle studies were performed to further confirm the anti-cancer activity of the top-ranked compound MLNC.

Syntheses, structures and biological activities of new pyridinyl lactones

Several novel lactones containing either a pyridin-3-yl or a pyridin-2-yl ring in their structure were synthesized: trans δ halolactones 6–8a,b (chloro‑, bromo‑ and iodo-), γ iodolactone 11b and isomeric γ hydroxylactones 9–10a,b. Their structures were confirmed by NMR, IR and HR-MS and additionally by single crystal X-ray diffraction for trans δ bromolactone 6a, trans δ chlorolactone 7b and γ hydroxylactone 10b. Spectral analyses were further supported by DFT calculations. In testing of the compounds for antibacterial activity, none of the lactones exhibited activity against several bacteria strains. However, all lactones exhibited significant cytotoxicity against normal eukaryotic murine fibroblast L929 and human gastric adenocarcinoma AGS cell lines with lactones possessing a pyridine-2-yl ring being more cytotoxic than their pyridine-3-yl counterparts.

Antibacterial, mosquito larvicidal, and cytotoxicity potential of AgNPs synthesized using Pittosporum undulatum under in vitro conditions

In this study, the phytochemical profile and silver nanoparticle (AgNPs)-synthesizing ability of Pittosporum undulatum methanol extract were investigated. Furthermore, biological applications of the AgNPs, such as antibacterial effect (against Klebsiella pneumoniae, Staphylococcus aureus, Bacillus subtilis, and Escherichia coli), mosquito larvicidal effect (against Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti), and cytotoxicity (against fibroblast cell line L929) were evaluated using in vitro experiments. The phytochemical analysis revealed that the methanol extract contained cardiac glycosides, terpenoids, saponins, alkaloids, flavonoids, glycosides, coumarins, phenolics, and tannins. Furthermore, standard characterization techniques such as UV–Vis spectrometry, SEM, TEM, FTIR, and XRD confirmed that the methanol extract of P. undulatum effectively synthesized the AgNPs. The synthesized AgNPs had a spherical shape and size of 20–200 nm. The bactericidal analysis revealed that the AgNPs have dose-dependent antibacterial activity. The MTT assay showed that the AgNPs were bio-compatible up to a dosage of 250 μg mL−1 in the normal fibroblast cell line L929. Furthermore, the LC50 values for AgNPs against larvae of An. stephensi, Cx. quinquefasciatus, and Ae. aegypti were 0.4, 4.7, and 1.2 ppm, respectively. Field trials demonstrated that the larvicidal effect was enhanced within 24–72 h, and the rate of reduction increased over time. Thus, our findings provide an ideal sustainable AgNP bio-pesticide to combat filarial, dengue, and malaria vectors.

Uridine-Loaded Polycaprolactone Nanofiber Mats as a Novel Wound Dressing

In the current study, a novel wound dressing material for an effective wound healing was developed by loading Uridine (URD), an endogenous compound known for its regenerative properties, into polycaprolactone (PCL) nanofibers. Initially, PCL nanofibers without URD were fabricated from different PCL solutions (7, 8, 10 and 11% w/w) by electrospinning and optimum PCL concentration (10% w/w) for URD loading was determined. After loading URD at different concentrations (0.1, 0.5 and 1% w/w) into 10% PCL solution, PCL/URD nanofibers were electrospun. Structural characteristics, release kinetics as well as in vitro and in vivo effects of the PCL/URD nanofibers were studied and in vivo effects were compared with a conventional wound dressing material. Loading URD increased nanofiber diameters from 248 to 509 nm and decreased contact angles from 123.76° to 94.3° with increasing URD concentrations. URD showed a burst release in the first 60 min following a more gradual release up to the 5th day which best fitted with Korsmeyer–Peppas model. PCL/URD mats provided enhanced viability in vitro in MTT assay using mouse L929 fibroblast cell line. Furthermore, in vivo wound closure studies revealed an immediate and robust wound healing in rats treated with PCL/URD mats compared to PCL mats without URD as well as the conventional wound dressing material. These data suggest that URD-loaded PCL nanofiber mats are promising materials as wound dressing.Graphical abstract

Development and characterization of ferulic acid-loaded chitosan nanoparticle embedded- hydrogel for diabetic wound delivery

Diabetic wounds present a significant global health challenge exacerbated by chronic hyperglycemia-induced oxidative stress, impeding the natural healing process. Despite various treatment strategies, diabetic foot ulceration lacks standardized therapy. Ferulic acid (FA), known for its potent antidiabetic and antioxidant properties, holds promise for diabetic wound management. However, oral administration of FA faces limitations due to rapid oxidation, stability issues, and low bioavailability. The topical application of FA-loaded chitosan nanoparticles (FA-CSNPs) has emerged as a promising approach to overcome these challenges. Here, we report the development of a sustained-release formulation of FA-CSNPs within a hydrogel matrix composed of Chitosan and gelatin. The FA-CSNPs were synthesized using the ionic gelation method andoptimized through a Central Composite Design (CCD) approach. Characterization of the optimized nanoparticles revealed spherical morphology, a particle size of 56.9 ± 2.5 nm, and an impressive entrapment efficiency of 90.3 ± 2.4 %. Subsequently, an FA-CSNPs-loaded hydrogel was formulated, incorporating chitosan as a gelling agent, gelatin to enhance mechanical properties and cell permeation, and glutaraldehyde as a cross-linker. Comprehensive characterization of the hydrogel included pH, moisture loss, porosity, swelling index, rheology, water vapor transmission rate (WVTR), SEM, TEM, invitro drug release studies, antioxidant activity, antibacterial efficacy, cell cytotoxicity, cell migration studies on L929 fibroblast cell line, and stability studies. The stability study demonstrated negligible variations in particle size, zeta potential, and entrapment efficiency over 60 days, ensuring the stable nature of nanoparticles and hydrogel. This innovative delivery approach embedded within a hydrogel matrix holds significant promise for enhancing the therapeutic efficacy of FA-CSNPs-hydrogel in diabetic wound healing applications.

Insights into cellular interactions of characterized Mg–Al Layered Double Hydroxide on L929 cells

Layered double hydroxides are members of an anionic clay family, characterised by unique two-dimensional layered structures and lend versatility in various applications. These biocompatible compounds have the potential to get intercalated with biological compounds and physico-chemically adsorbed onto organic molecules. Thus, making them important candidates for pharmaceutical and biomedical purposes. This study aims to synthesise, characterise and investigate the cellular toxicity interactions of Mg–Al LDH towards the mouse fibroblast L929 cell line. The Mg–Al LDH was synthesized by a meticulous process of co-precipitation followed by the hydrothermal method to ensure a well-defined and stable structure for suitable biological application. Characterisation techniques like Dynamic Light Scattering, Zeta potential, Scanning Electron Microscopy, Fourier transform infrared, and X-ray diffraction analysis were employed to provide deeper insights into the physiochemical properties and structural integrity of the synthesized Mg–Al LDH. The investigation of cellular interactions with the L929 fibroblast cell line served to assess the biocompatibility and potential cytotoxic effects of Mg–Al LDH. This was observed by assessing the morphological changes and evaluating the cytotoxic effects of Mg–Al LDH by utilising various techniques like phase contrast microscopy, fluorescent staining, and Giemsa staining. The cellular metabolic activity was assessed by MTT assay, and the subcellular lysosomal alteration was examined using the fluorescent staining method by the acridine orange staining. The dose-dependent response observed in the cellular interaction underscores the importance of dosage considerations for potential biomedical applications. By elucidating the dose-response relationship, this study contributes valuable information for the safe and effective usage of LDH in biomedical contexts.

Barleria lupulina leaf extract-assisted biosynthesis of cobalt ferrite nanoparticles: Characterization and anticancer activity against MCF-7 cells

This study reports the synthesis of Cobalt ferrite (CoFe2O4) nanoparticles (NPs) by a green synthesis method using the leaf extract of Barleria Lupulina. The X-ray diffraction (XRD) analysis confirms the formation of a single-phase cubic (Fd3m) structure and from the Scherrer formula the average crystallite size (30.07 nm) calculated matches with that obtained from W-H plot(34.66 nm). A bandgap of 2.02 eV was observed from the UV–Vis-DRS analysis. Fourier transform infrared spectroscopy (FTIR) was used to confirm the characteristic functional groups present in the spinel ferrite. The investigation using scanning electron microscopy (SEM) shows aggregates of nanoparticles and EDX analysis gives the chemical composition of the green synthesized ferrite sample. The distribution of particle-sizes and colloidal-stability were estimated by DLS and zeta-potential measurements. The M−H plot confirmed the ferromagnetic nature of the prepared nanoparticles. Beyond the realm of material science, we ventured into the realm of biological activity. Our synthesized cobalt ferrite nanoparticles were assessed for their toxicity on human breast cancer cell lines (MCF-7) as well as normal L929 fibroblast cell lines by MTT assay. The results show potent anti-cancer activity of the ferrite sample (LC50 value 77.92 µg/ml) while sparing normal cells from excessive toxicity (LC50 value 252.34 µg/ml). The results of cell viability, changes in cell morphology, and cell cycle analysis revealed that cobalt ferrite nanoparticles triggered apoptosis, and hindered cell adhesion and migration of MCF-7 cells, potentially through elevated reactive oxygen species generation. This dual action, where the nanoparticles combat cancer effectively while minimizing harm to healthy cells, holds significant promise in the field of oncology.

Polydopamine Coating of Graphitic Carbon Nitride, g-C3N4, Improves Biomedical Application.

Graphitic carbon nitride (g-C3N4) is an intriguing nanomaterial that exhibits photoconductive fluorescence properties under UV-visible light. Dopamine (DA) coating of g-C3N4 prepared from melamine was accomplished via self-polymerization of DA as polydopamine (PDA). The g-C3N4 was coated with PDA 1, 3, and 5 times repeatedly as (PDA@g-C3N4) in tris buffer at pH 8.5. As the number of PDA coatings was increased on g-C3N4, the peak intensity at 1512 cm-1 for N-H bending increased. In addition, the increased weight loss values of PDA@g-C3N4 structures at 600 °C from TGA thermograms confirmed that the coating was accomplished. The band gap of g-C3N4, 2.72 eV, was reduced to 0.87 eV after five coatings with PDA. A pristine g-C3N4 was found to have an isoelectric point (IEP) of 4.0, whereas the isoelectric points of 1PDA@g-C3N4 and 3PDA@g-C3N4 are close to each other at 3.94 and 3.91, respectively. On the other hand, the IEP of 5PDA@g-C3N4 was determined at pH 5.75 assuming complete coating with g-C3N4. The biocompatibility of g-C3N4 and PDA@g-C3N4 against L929 fibroblast cell lines revealed that all PDA@g-C3N4 coatings were found to be biocompatible up to a 1000 mg/mL concentration, establishing that PDA coatings did not adversely affect the biocompatibility of the composite materials. In addition, PDA@g-C3N4 was screened for antioxidant potential via total phenol content (TPC) and total flavonoid content assays and it was found that PDA@g-C3N4 has recognizable TPC values and increased linearly with an increased number of PDA coatings. Furthermore, blood compatibility of pristine g-C3N4 is enhanced considerably upon PDA coating, affirmed by hemolysis and the blood clotting index%. Additionally, α-glucosidase inhibitory properties of PDA@g-C3N4 structures revealed that 67.6 + 9.8% of this enzyme was evenly inhibited by 3PDA@g-C3N4 structure.

Development of thymol-loaded polymeric films designed as wound dressing materials: Physical, antioxidant, antibacterial, cytocompatibility, and wound healing properties

In the presented study, the potential of thymol-loaded films consisting of pullulan (PUL) and kappa carrageenan (CARR) to be used as wound dressing materials was examined. The films were characterized by FTIR (Fourier transform infrared), TGA (thermogravimetric analysis) and SEM (scanning electron microscopy) analyses. Swelling and hydrolytic degradation behavior, water vapor permeability rate, and mechanical properties, which are important parameters for the films to be evaluated as wound dressing materials, were determined. Antioxidant and antibacterial activities of the films were examined. Additionally, in vitro cytotoxicity and in vitro wound healing activity of the films were evaluated in the L929 fibroblast cell line. The results show that the non-toxic biopolymeric film containing 5 % thymol has the potential to be a promising antioxidant and antibacterial wound dressing, effectively reducing the scratch open area for wound dressing application.

Evaluation of cytocompatibility and cell proliferation of electrospun chitosan/polyvinyl alcohol/montmorillonite clay scaffold with l929 cell lines in skin regeneration activity and in silico molecular docking studies

The present investigation describes the development of a novel Chitosan/Polyvinyl Alcohol/Montmorillonite Clay (CS/PVA/MMT) scaffold by adopting an electrospinning method, and their biocompatibility was evaluated in vitro with L929 fibroblast cell line to ascertain its use in wound healing applications. The fabricated scaffold was characterized using analytical techniques. FT-IR measurement exhibited the existence of relevant functional groups and XRD implies scaffolds' amorphous nature. The scaffold's morphology and pore diameter were assessed using TEM and SEM. The pore diameter of the as-prepared scaffold was approximately 125 nm. The antimicrobial assay of the scaffold was evaluated against selected pathogens which demonstrated higher antimicrobial efficacy. The scavenging activity tested using the DPPH assay showed remarkable scavenging capability. The wound healing properties were tested through the Cytotoxicity assay conducted on the L929 assay which proved the scaffold to be a suitable material for cell proliferation. Also, a Molecular docking investigation was carried out for CS/PVA/MMT ligand using human neutrophil elastase (HNE) 1H1B protein as a receptor in the CB-Dock server. Studies conducted in silico revealed strong interaction and high binding energy ratings of CS/PVA/MMT ligand with key residues of human neutrophil elastase (HNE) 1H1B proteins that help in tissue regeneration activity.

Psidium guajava-mediated green synthesis of Fe-doped ZnO and Co-doped ZnO nanoparticles: a comprehensive study on characterization and biological applications.

The efficacy of nanoparticles (NPs) in healthcare applications hinges on their biocidal activity and biocompatibility. This research is dedicated to green-synthesized NPs with potent biocidal properties, aiming for high inhibition rates in bacterial infections and offering a multifunctional application, including potential use in anticancer therapy, in comparison to traditional antibiotics. The present study focuses on synthesis of zinc oxide (ZnO) nanoparticles (NPs), including iron-doped ZnO (GZF) and cobalt-doped ZnO (GZC), using the green co-precipitation method involving Psidium guajava (P. guajava) leaf extract. The physicochemical properties of the synthesized NPs were analyzed using various characterization techniques. The antibacterial and anticancer activity depends on the generation of reactive oxygen species (ROS), particle size, surface area, oxygen vacancy, Zn2+ release, and diffusion ability. The antibacterial activity of the synthesized NPs was tested against various Gram-positive (Streptococcus pneumoniae (S. pneumoniae), Bacillus subtilis (B. subtilis) and Gram-negative (Klebsiella pneumoniae (K. pneumoniae), and Pseudomonas aeruginosa (P. aeruginosa) bacterial strains. The zone of inhibition showed higher activity of GZC (18-20mm) compared to GZF (16-19mm) and GZO (11-15mm) NPs. Moreover, anticancer studies against blood cancer cell line (MOLT-4) showed half-maximal inhibitory concentration of 11.3μg/mL for GZC compared to GZF and GZO NPs with 12.1μg/mL and 12.5μg/mL, respectively. Cytotoxicity assessments carried out on the fibroblast L929 cell line indicated that GZO, GZF, and GZC NPs demonstrated cell viabilities of 85.43%, 86.66%, and 88.14%, respectively. Thus, green-synthesized GZC NPs hold promise as multifunctional agents in the biomedical sector.

Investigation of the mutagenic, cytotoxic and antimicrobial effect of bikaverin mycotoxin

Bikaverin is a reddish pigment produced by different fungi species (Mycogone jaapii, Verticillium agaricinum, Beauveria bassiana, Paecilomyces fumosoroseus, Polyporus sulphureus), mainly of the Fusarium genus. Due to its pigment feature, bikaverin can be used as a dye in various fields in the industry. However, it is extremely important to study the mutagenic/genotoxic effects, cytotoxic effects and antimicrobial properties of bikaverin for application of industrial areas. In the study, the mutagenic, cytotoxic and antimicrobial effects of bikaverin were investigated. The mutagenic effect of bikaverin was studied with the Ames test. Salmonella typhimurium TA97a, TA98, TA100, TA102 and TA1535 strains were used in the test. Five different doses of bikaverin (0.075, 0.1, 0.2, 0.3 and 0.5 μg/plate) were tested against strains. It was determined that there was no mutagenic effect of bikaverin. The cytotoxicity of bikaverin was evaluated by MTT test on L929 fibroblast cell line. Bikaverin demonstrated no cytotoxic effect on L929 fibroblast cell line, according to cell viability calculations that showed >73% for all concentrations (1, 0.5, 0.4, 0.3, 0.2, 0.1, 0.075, 0.05, 0.025, 0.01, 0.005 and 0.001 μg/mL) examined. Bikaverin's IC50 value was determined to be 1.79±0.51 g/mL. The antimicrobial activity of the bikaverin was evaluated by using the microdilution method. Bikaverin was found to have antimicrobial effects on Methicillin resistant Staphylococcus aureus, Vancomycin resistant Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Candida albicans and Candida krusei, as MIC values ranged from 1.25 -5 µg/ mL.

Cyclosporin A-loaded dissolving microneedles for dermatitis therapy: Development, characterisation and efficacy in a delayed-type hypersensitivity in vivo model

Several drugs can be used for treating inflammatory skin pathologies like dermatitis and psoriasis. However, for the management of chronic and long-term cases, topical administration is preferred over oral delivery since it prevents certain issues due to systemic side effects from occurring. Cyclosporin A (CsA) has been used for this purpose; however, its high molecular weight (1202 Da) restricts the diffusion through the skin structure. Here, we developed a nano-in-micro device combining lipid vesicles (LVs) and dissolving microneedle array patches (DMAPs) for targeted skin delivery. CsA-LVs allowed the effective incorporation of CsA in the hydrophilic DMAP matrix despite the hydrophobicity of the drug. Polymeric matrix composed of poly (vinyl alcohol) (5% w/v), poly (vinyl pyrrolidine) (15% w/v) and CsA-LV dispersion (10% v/v) led to the formation of CsA-LVs@DMAPs with adequate mechanical properties to penetrate the stratum corneum barrier. The safety and biocompatibility were ensured in an in vitro viability test using HaCaT keratinocytes and L929 fibroblast cell lines. Ex vivo permeability studies in a Franz-diffusion cell setup showed effective drug retention in the skin structure. Finally, CsA-LVs@DMAPs were challenged in an in vivo murine model of delayed-type hypersensitivity to corroborate their potential to ameliorate skin inflammatory conditions. Different findings like photon emission reduction in bioluminescence study, normalisation of histological damage and decrease of inflammatory cytokines point out the effectivity of CsA-LVs@DMAPs to treat these conditions. Overall, our study demonstrates that CsA-LVs@DMAPs can downregulate the skin inflammatory environment which paves the way for their clinical translation and their use as an alternative to corticosteroid-based therapies.Graphical

Influence of oleic acid coating on the magnetic susceptibility and Fenton reaction-mediated ROS generation by the iron oxide nanoparticles

Fenton reaction-mediated reactive oxygen species (ROS) generation by the iron oxide nanoparticles (IONPs) is responsible for its antibacterial activity. In general, IONPs are surface-coated to facilitate stability, control over size, biocompatibility, solubility, etc. We hypothesize that the extent of surface coating onto the IONPs might affect Fenton reaction-mediated ROS generation, which would eventually impact its antibacterial activity. In the present study, IONPs were prepared using the co-precipitation method, and different weights of oleic acid (OA) were loaded onto the IONPs. Pristine IONPs and oleic acid-coated iron oxide nanoparticles (OA-IONPs) were characterized using Fourier transform-infrared spectroscopy, dynamic light scattering, transmission electron microscopy, X-ray diffraction, vibrating sample magnetometry, goniometer, and thermogravimetric analysis. We found that magnetic susceptibilities of the IONPs were significantly enhanced with an increase in OA loading on the IONPs. The antibacterial study showed that the percentage inhibition was inversely related to the extent of oleic acid coating on the IONPs. The dependency of ROS generation on the extent of surface coating over IONPs was demonstrated using the 2’,7’-dichlorodihydrofluorescein diacetate (DCFDA) assay. Although pristine IONPs showed the least ROS generation, they exhibited maximum percentage inhibition of bacteria. This might be due to mechanical damage to the bacterial cells because of their crystalline nature. In vitro biocompatibility study conducted on L929 fibroblast cell lines indicated that all the nanoparticle preparations were cytocompatible. This study concluded that the extent of surface coating influences the Fenton reaction-mediated ROS generation and also the magnetic susceptibilities of the IONPs.

Isolation and Identification of Effective Probiotics on Drug-Resistant Acinetobacter baumannii Strains and Their Biofilms.

This study aimed to identify, assess, and isolate strong lactobacilli demonstrating broad antibacterial and anti-biofilm activity against drug-resistant strains of Acinetobacter baumannii. Additionally, the mechanism of inhibition of these organisms was to be determined. Over a 6-month period (from December 2021 to June 2022), 53 clinical A. baumannii strains were collected from clinical samples. Twenty probiotic strains were isolated from local dairy products. Antibacterial activity of Lactobacillus strains' cell-free supernatant (CFS) was identified using the agar well diffusion method and the microbroth dilution test. Anti-biofilm effect was performed by the microtiter plate assay. The MTT assay was also used to look into the probiotics' cytotoxic effects on the L929 fibroblast cell line. During the 6-month period, 53 clinical A. baumannii strains were obtained and identified. Out of 20 lactobacillus strains, the CFS of a lactobacillus strain (named L9) showed an inhibitory effect against all A. baumannii strains. Using the broth microdilution method, it was shown that the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of CFS extracts of L9 strains against A. baumannii strains were both ¼ mg/mL. The result of the anti-biofilm showed that the selected probiotic could inhibit biofilm formation. The most common organic acid produced by all Lactobacillus strains, according to the HPLC method, was lactic acid, which was followed by acetic acid. The L929 fibroblast cell line was used in the cytotoxicity assay, which revealed that 100% of the cells in the L929 fibroblast cell line survived treatment with successive doses of CFSs for a full day. The probiotic strain isolated from local yogurt in this study showed potential anti-biofilm and antimicrobial properties against all drug-resistant Acinetobacter isolates. Given the increasing interest in probiotic microorganisms based on their high health benefits, further studies are recommended on the mechanisms of action between probiotics and A. baumannii strains to find new solutions for biological control and treatment of these infections without the use of antibiotics.