Superior Antibacterial Activity Research Articles

Antibacterial and surface properties of post-light-activated metal-free phthalocyanine-deposited TiO2 nanotube smart surfaces.

The utilisation of implantable medical devices has become safer and more prevalent since the establishment of sterilisation methods and techniques a century ago. Nevertheless, device-associated infections remain a significant and growing concern, particularly in light of the continued rise in the number of medical device implantations. This underscores the imperative for the development of efficacious prevention and treatment strategies for device-associated infections, as well as further investigation into the design of innovative antibacterial surfaces for medical device applications. The motivation of this work is to investigate the post-light-activated antibacterial photosensitive surfaces fabricated on medical titanium (Ti) surfaces. Thus, in this work, metal-free phthalocyanine (H2Pc)-deposited TiO2 nanotube (TNT) array smart photosensitive surfaces were fabricated on titanium (Ti) surfaces for medical device applications. First, well-ordered nanotube surfaces were produced on titanium using an anodic oxidation (AO) process. Then, H2Pc was accumulated onto TNT surfaces using a physical vapour deposition (PVD-TE) process. H2Pc-deposited TNT surfaces were fabricated on Ti substrates by combining AO and physical vapour deposition (PVD-TE) processes in this work for the first time in the literature. H2Pc was largely coated onto TNT arrays and exhibited elemental homogeneity throughout the whole surface. The contact angle of H2Pc-deposited TNT surfaces was about 89° whereas other Ti and TNT surfaces demonstrated hydrophilic characteristics. Therefore, they exhibited remarkable hydrophobic behavior in terms of antibacterial properties. Importantly, compared to Ti and TNT surfaces, the bacterial inhibition on sunlight-activated H2Pc-deposited TNT surfaces was 94.9% for S. aureus and 97.3% for E. coli, respectively. According to these results, H2Pc-deposited TNT innovative surfaces provided superior antibacterial activity post-light-activation under sunlight due to their photosensitive character.

SYNTHESIS OF VANADIUM GRAPHITIC-CARBON NITRIDE(V/g-C₃N₄) COMPOSITE FOR BIOLOGICAL APPLICATION

The synthesis of vanadium carbon nitride (V/g-C₃N₄) composites has been explored for their potential as antimicrobial and antioxidant agents. These materials were evaluated against Escherichia coli and Staphylococcus aureus using a combination of disc diffusion, well diffusion, and biofilm inhibition assays. Antioxidant properties were assessed through DPPH free radical scavenging analysis. V/g-C₃N₄ composites demonstrated notable antimicrobial activity, exhibiting inhibition zones comparable to ciprofloxacin, the standard antibiotic. In disc and well diffusion assays, the composites significantly inhibited the growth of both bacterial strains, with Staphylococcus aureus exhibiting marginally higher sensitivity. Biofilm inhibition assays revealed effective suppression of bacterial adhesion and biofilm formation, achieving biofilm inhibition percentages of approximately 17% for E. coli and 22.6% for S. aureus. These results underscore the potential of V/g-C₃N₄ in curbing biofilm-associated infections. Antioxidant activity was quantitatively measured using the DPPH assay, with radical scavenging efficiency consistently exceeding 52%. This performance highlights the dual functionality of V/g-C₃N₄ composites as both antimicrobial and antioxidant agents. Comparatively, ciprofloxacin demonstrated superior antibacterial activity but lacked antioxidant properties, emphasizing the multifaceted advantage of V/g-C₃N₄ composites in biomedical applications. The shake-flask method further validated the biocompatibility and antimicrobial effectiveness of V/g-C₃N₄. This study indicates that vanadium carbon nitride composites hold promise as versatile agents in combating oxidative stress and bacterial infections, particularly in environments where biofilm formation exacerbates antimicrobial resistance. Future studies will focus on optimizing the composite synthesis and exploring its efficacy against a broader range of pathogens.

Sulfonium-based polymethacrylamides for antimicrobial use: influence of the structure and composition.

We are facing a shortage of new antibiotics to fight against increasingly resistant bacteria. As an alternative to conventional small molecule antibiotics, antimicrobial polymers (AMPs) have great potential. These polymers contain cationic and hydrophobic groups and disrupt bacterial cell membranes through a combination of electrostatic and hydrophobic interactions. While most examples focus on ammonium-based cations, sulfonium groups are recently emerging to broaden the scope of polymeric therapeutics. Here, main-chain sulfonium polymers exhibit good antimicrobial activity. In contrast, the potential of side-chain sulfonium polymers remains less explored with structure-activity relationships still being limited. To address this limitation, we thoroughly investigated key factors influencing antimicrobial activity in side-chain sulfonium-based AMPs. For this, we combined sulfonium cations with different hydrophobic (aliphatic/aromatic) and hydrophilic polyethylene glycol (PEG) groups to create a library of polymers with comparable chain lengths. For all compositions, we additionally examined the position of cationic and hydrophobic groups on the polymer backbone, i.e., we systematically compared same center and different center structures. Bactericidal tests against Gram-positive and Gram-negative bacteria suggest that same center polymers are more active than different center polymers of similar clog P. Ultimately, sulfonium-based AMPs show superior bactericidal activity and selectivity when compared to their quaternary ammonium cationic analogues.

Nanoformulation of Polymyxin E Through Complex Coacervation: A Pharmacokinetic Analysis.

Objectives: Polymyxin E (PME), a polymyxin antibiotic, serves as a final resort against antibiotic resistance. Nephrotoxicity is the primary concern when employing PME. To alleviate this issue, researchers have explored strategies including dosing adjustments and innovative formulations. This study employed complex coacervation to create PME nanoformulations, capitalizing on PME's charge properties. The research question and hypothesis posed pertained to whether neutralization of PME's positive charge during formulation would reduce its antibiotic efficacy and alter its tissue distribution and other pharmacokinetic parameters. Our objective was to evaluate the capability of complex coacervation to mitigate the adverse effects of PME while preserving its antibacterial potency and therapeutic effectiveness. Methods: Three negatively charged polyions: potassium sucrose octasulfate, polytamic acid, and sodium hyaluronate, were used for formulation. We performed characterization on the nanocomplex formed by the polyions and PME. The nanoformulations underwent several tests, including minimum inhibitory concentration, in vivo efficacy on an infected mouse model, pharmacokinetic assessments, tissue distribution, and toxicity. Results: the three polyions formed coacervation complexes with PME at varying charge ratios, yielding nanoparticles smaller than 30 nm with low polydispersity (PDI < 0.3). The results demonstrated that complex coacervation-mediated PME nanoformulations exhibited equivalent or superior antibacterial activity, increased maximum tolerant dose, and fewer adverse reactions in animal tests. Conclusions: Utilizing complex coacervation, PME nanoformulations were developed, demonstrating efficacy in the formulation process. Pharmacokinetic assessments revealed absorption and distribution profiles akin to those of standalone PME. The positive charge inherent in PME causing its toxicity was mitigated after complex coacervation.

Photocatalytic, antibacterial and antioxidant study of Vitex negundo mediated green synthesized nickel and neodymium doped zinc oxide nanoparticles

This investigation delves into diverse attributes of environmentally friendly nickel-doped zinc oxide and neodymium doped zinc oxide nanoparticles. It focuses on evaluating their effectiveness in photocatalysis, antibacterial activity and antioxidant properties. Utilizing a sustainable synthesis approach incorporating phytochemicals from Vitex negundo, hexagonal structures of both nickel-doped zinc oxide and neodymium-doped zinc oxide nanoparticles were confirmed through X-ray diffraction analysis. Transmission electron microscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy analyses identified spherical nanoparticles with size between 8 and 15 nanometers. Photocatalytic assessments using methyl green dye degradation demonstrated promising results for both nickel-doped zinc oxide and neodymium-doped zinc oxide nanoparticles. Antibacterial tests showcased nanoparticle’s ability to disrupt Bacillus subtilis and Escherichia coli, with neodymium doped zinc oxide nanoparticles exhibiting superior antibacterial activity. Antioxidant potential, evaluated through 2,2-diphenyl-1-picrylhydrazyl free radical assay, highlighted nanoparticles radical-scavenging ability, with neodymium doped zinc oxide nanoparticles showing enhanced activity due to phytochemicals introduced during green synthesis. This research innovates through green synthesis of nickel-doped zinc oxide and neodymium-doped zinc oxide nanoparticles, capitalizing on their distinctive properties for synergistic applications. The study provides valuable insights into potential future applications, offering novel solutions for environmental remediation and biomedical purposes.

Green Synthesis of Urethane-Linked Tamarind Seed Xyloglucan: Thermal Stability, Antibacterial Properties, andDFT Study.

This study presents a feasible, one-pot synthesis approach for the preparation of a composite biopolymer material derived from tamarind seed xyloglucan (XG) by utilizing isocyanate chemistry. Through a facile reaction process, urethane bonds are formed in XG, resulting in the formation of a crosslinked network. FTIR spectra confirm the successful urethane link formation in XG via the OH-NCO reaction, and CHN analysis provides insights into the elemental composition. The synthesized XG-urethane composite (U-XG) exhibits enhanced thermal stability compared to native XG, with an enhanced degradation temperature (T5%) of 276°C (XG marked T5% at a lower temperature of 163°C). The optimized geometric structure, hydrogen bond types, and hydrogen bond strength of the synthesized U-XG are computationally studied by density functional theory (DFT) at the B3LYP/6-31G(d,p) level. This study also investigates the antibacterial efficacy of both XG and U-XG against a panel of pathogenic bacteria, including gram-positive bacteria such as S. aureus and S. epidermidis, as well as gram-negative E. coli. The U-XG demonstrates superior antibacterial activity against S. epidermidis compared to pristine XG. This research showcases the feasibility of a one-pot synthesis approach for preparing urethane-linked XG with enhanced thermal properties and superior antibacterial activity, offering promising prospects for biomedical and antimicrobial applications.

Comparative metabolomic study of twelve Acacia species by UHPLC-q-tof-ESI-MS coupled with chemometrics in correlation with antibacterial activity.

Genus Acacia comprises around 1500 species. They are widely used to treat inflammation as well as bacterial and fungal infections as they are enriched in phytochemicals, especially phenolics. The aim of this study was to evaluate the antibacterial activity of leaves' methanolic extracts of twelve Acacia species growing in Egypt against Vibrio parahaemolyticus, Salmonella enterica, Listeria monocytogens, Klebsiella pnemoniae, Bacillus aquimaris, Bacillus subtilis, and Escherichia coli. These species are Acacia nilotica (wild and cultivated), Acacia seyal, Acacia auriculiformis, Acacia saligna, Acacia xanthophloea, Acacia tortilis subsp. raddiana (Gabal Elba and Aswan), Acacia tortilis, Acacia laeta (wild and cultivated), and Acacia albida. Furthermore, to study the metabolomic composition and variation among these species using ultra-high-performance liquid chromatography-electrospray ionization quadrupole time of flight mass spectrometry (UHPLC-q-tof-ESI-MS) coupled with multivariate statistical analysis and correlate it to the antibacterial potential. Results showed that Acacia nilotica (AN) has superior antibacterial activity over the other species. In addition, it exhibited a distinct segregation in Principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA). Full profiling of AN using UHPLC-ESI-q-tof-MS revealed 42 phenolics mainly catechins. It was further subjected to bio-guided fractionation and revealed the presence of methyl gallic acid, gallic acid, catechin gallate, and digallate isomers in its most bioactive fraction. These compounds were identical to the compounds annotated as VIPs and were responsible for the segregation of AN in both PCA and PLS-DA analyses. Hence, this study sheds light on the use of chemometrics as an early tool for the detection of bioactive compounds.

Fabrication and characterization of silver nanowire-coated porous alginate wet-laid webs for wound dressing applications

Fabrication and characterization of silver nanowire-coated porous alginate wet-laid webs for wound dressing applications

Bougainvillea glabra-mediated synthesis of Zr₃O and chitosan-coated zirconium oxide nanoparticles: Multifunctional antibacterial and anticancer agents with enhanced biocompatibility.

The effectiveness and safety of nanomaterials (NMs) are essential for their use in healthcare. This study focuses on creating NPs with multifunctional antibacterial and anticancer properties to combat bacterial infections and cancer disease more effectively than traditional antibiotics. This study investigates the synthesis of Zr3O and chitosan (ch) coated zirconium oxide nanoparticles (chZrO NPs) using Bougainvillea glabra (B. glabra) plant extract through a green, one-pot precipitation method. The synthesized NPs were analyzed using various techniques. Their antibacterial properties are attributed to the production of reactive oxygen species (ROS), influenced by their size, large surface area, oxygen vacancies, ion release, and diffusion capabilities. The chZrO NPs showed superior antibacterial activity compared to Zr3O and chitosan alone, with effective inhibition against both Gram-positive bacteria (S. aureus and B. subtilis) and Gram-negative bacteria (E. coli and P. aeruginosa). Additionally, anticancer studies of chZrO NPs demonstrated significant activity against colon cancer HCT116 cells with C50 values of 4.98 μg/mL compared to chitosan and Zr3O with 9.62, 6.69 μg/mL, while biocompatibility tests on L929 cells confirmed their safety showing 93 % cell viability compared to ch and Zr3O. These findings suggest that chZrO NPs are promising candidates for future use in clinical and healthcare applications.

Novel Foamed Magnesium Phosphate Antimicrobial Bone Cement for Bone Augmentation.

In dental implant surgery, infection is identified as the primary factor contributing to the failure of bone grafts. There is an urgent need to develop bone graft materials possessing antibacterial characteristics to facilitate bone regeneration. Magnesium phosphate bone cement (MPC) is highly desirable for bone regeneration due to its favorable biocompatibility, plasticity, and osteogenic capabilities. However, the limited porosity of conventional MPC hinders the nutrient supply, gas diffusion, and cell infiltration, thereby compromising its osteogenic efficacy. This research focused on the fabrication of a highly porous MPC (CaCO3/CA-MPC) by incorporating citric acid (CA) and calcium carbonate (CaCO3) as foaming agents. The resulting material demonstrated enhanced physicochemical properties, bioactivity, and antimicrobial effects. When compared with conventional MPC, human periodontal ligament stem cells (hPDLSCs) showed improved osteogenic differentiation when cultured with CaCO3/CA-MPC. The inclusion of foaming agents significantly enhanced the antimicrobial efficacy of MPC against both Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli). The results of invivo anti-infection experiments in rats revealed that 3%CaCO3/CA-MPC displayed superior bactericidal activity compared with Bio-Oss and control groups (p < 0.05), thereby enhancing the anti-infective outcomes post-bone grafting and stimulating osteogenesis in the infected bone defect region. The study demonstrated that MPC containing 3%CaCO3/CA exhibited excellent antimicrobial and osteogenic properties both invitro and invivo, suggesting its potential as a promising candidate as bone graft material for dental implant surgeries.

Exploration of antimicrobial activity and antioxidant potential of Loranthus Cordifolius plants from Mirpur Azad Kashmir, Pakistan

Loranthus cordifolius is a parasitic plant, and its extracts are traditionally used in some cultures as antimicrobial and immunological medicines. Literature suggests that bioactive compounds produced by a parasitic plant could potentially be influenced by the host plant's own chemical composition, playing a role in the adaptogenic properties of the parasitic plant. In the present research, L. cordifolius shrubs were collected from host species Phyllanthus emblica and Juglans regia, and extracts were obtained using chloroform, petroleum ether, methanol, and water. The phytochemical profile, encompassing alkaloids, flavonoids, cardiac glycosides, tannins, terpenoids, and saponins, was qualitatively and quantitatively assessed, revealing varying concentrations based on solvents and hosts. Leaf extracts from L. cordifolius (Host P. emblica) displayed superior antifungal and antibacterial activities compared to those from L. cordifolius (Host J. regia). Notably, leaf extracts from L. cordifolius (Host P. emblica) exhibited effective results, including minimum inhibitory effect, Minimum Bactericidal Concentration, and Minimum Fungicidal Concentration. The leaf extracts of L. cordifolius (Host P. emblica) produced the best activity indices of 0.97, 0.97, 1.02, and 0.85 against the test organisms E. coli, S. aureus, P. aeruginosa, and B. subtilis, respectively, as compared to leaf extracts of L. cordifolius (Host J. regia) with values of 0.95, 0.95, 0.94, and 0.82 Stem extracts from L. cordifolius plants (Host P. emblica) demonstrated higher DPPH scavenging effect, total antioxidant activity, and total phenolic contents. These findings suggest that leaf extracts, particularly from host P. emblica, show promise as potential sources of green medicine due to their notable antimicrobial and antioxidant properties compared to the L. cordifolius plants from the host J. regia.

Superhydrophilic self-cleaning cotton fabric with enhanced antibacterial and UV protection properties

AbstractA multifunctional cotton fabric with superior photocatalytic self-cleaning, antibacterial activity and UV protection was prepared through treatment with TiO2/Pt/SiO2 colloid, clarifying the influence of coating formulation on these functionalities. The photocatalytic activity of coated fabrics under UV and white-fluorescent light was tested and synergistic effects of Pt and silica in enhancing the self-cleaning property of fabrics were demonstrated. Various molar ratios of Pt:Ti (0.01%, 0.1%, 0.5%, and 1%) and Ti:Si (50/50 and 30/70) were utilised in synthesising the colloids. The self-cleaning performance of fabrics was assessed through monitoring coffee stain removal efficiency and methylene blue (MB) dye degradation kinetics. The results demonstrated an effective photocatalytic self-cleaning property on fabrics coated with TiO2/Pt/SiO2 colloids. Increasing the concentrations of Pt and silica both contributed to enhancing the self-cleaning property. The fabric coated with ternary TiO2/Pt/SiO2 30/1/70 colloid resulted in 43.5% higher MB dye removal compared with pure TiO2 after 3h irradiation under visible light. Moreover, the fabrics containing Pt 1% dopant possessed excellent bactericidal activity against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria, regardless of the presence of silica. While the addition of silica slightly reduced the UV protection of coated fabrics, increasing the concentration of Pt to 1% increased the protection level to 45 + . Various characterisation techniques including SEM, XPS, XRD, and TEM were employed to study the Pt-doping of TiO2 nanoparticles, as well as the effect of Pt concentration, superhydrophilicity of silica, and the chemical composition of coatings on the functionalities of fabrics.

Acrylamide/Alyssum campestre seed gum hydrogels enhanced with titanium carbide: Rheological insights for cardiac tissue engineering.

This study investigates the use of acrylamide and Alyssum campestre seed gum (ACSG) to create hydrogel composites with enhanced electrical and mechanical properties by incorporating titanium carbide (TiC). The composites were analyzed through techniques such as FTIR, SEM, TEM, TGA, swelling, rheology, tensile, electrical conductivity, antibacterial, and MTT assays. XRD analysis showed that 0.5 % TiC NPs were exfoliated in the hydrogel, while 1 % was intercalated. SEM images showed that ACSG created a semi-interpenetrating polymer network with interconnected cavities averaging 9.1 μm, which reduced to 3.6 μm with 0.5%TiC and 51.8 nm with 1%TiC due to increased crosslinking density. TGA results confirmed hydrogel stability at autoclave temperatures. Rheological testing revealed that the hydrogel exhibited a maximum resistance of 317 kPa. The addition of 1 % TiC enhanced its electrical conductivity to 1.5 × 10-2S/cm, making it suitable for applications in cardiac tissue engineering. MTT assays confirmed the hydrogel's biocompatibility and demonstrated its superior antibacterial activity against Staphylococcus aureus compared to Escherichia coli. The AM/ACSG/TiC hydrogel is a promising material for cardiac tissue engineering because of its adjustable mechanical properties, excellent electrical conductivity, and strong compatibility with cell cultures. The addition of ACSG improves the hydrogel's rheological behavior, which is crucial for promoting effective cell growth.

Utilizing urban and agricultural waste for sustainable production of mesoporous hybrid nanocomposites in synthetic dye removal and antimicrobial activity.

The discharge of untreated dye waste from various industrial sectors into wastewater poses significant environmental and health risks. This study presents an innovative approach by developing a cost-effective and eco-friendly hybrid mesoporous nanocomposite, silver nanoparticles@mesoporous mango peel-derived carbon (AgNPs@MMC), synthesized from agricultural waste (mango peels) and urban waste (X-ray film waste). The core objectives of this work are: (i) recycling agricultural and urban waste to produce valuable materials; (ii) achieving effective removal of methyl violet 10B (MV10B) through simultaneous adsorption and photocatalytic degradation; and (iii) evaluating the antimicrobial properties of the developed material. The findings for identifying the optimal parameters for the adsorption and photodegradation process showed that 25mg of AgNPs@MMC can remove >98% of the MV10B dye in 30min at pH of 7. Furthermore, the nanocomposite maintained its high efficiency for five reuse cycles without significant loss in performance. This work highlights the dual functionality of AgNPs@MMC, combining adsorption and catalytic degradation, while also showcasing its potential for practical wastewater treatment applications. The nanocomposite's structural stability in water and its superior antibacterial activity against Gram-negative bacteria, such as Escherichia coli, Pseudomonas vulgaris, and Vibrio parahaemolyticus, further confirm its environmental suitability.

Shape and Size Dependent Antimicrobial and Anti-biofilm Properties of Functionalized MoS2.

Bacterial resistance, accelerated by the misuse of antibiotics, remains a critical concern for public health, promoting an ongoing exploration for cost-effective and safe antibacterial agents. Recently, there has been significant focus on various nanomaterials for the development of alternative antibiotics. Among these, molybdenum disulfide (MoS2) has gained attention due to its unique chemical, physical, and electronic properties, as well as its semiconducting nature, biocompatibility, and colloidal stability, positioning it as a promising candidate for biomedical research. The impact of the shape and size of MoS2 nanomaterials on the antibacterial activity remains largely unexplored. In this study, we investigated the effect of the shape and size of MoS2 nanomaterials, such as quantum dots, nanoflowers, and nanosheets, on antimicrobial and anti-biofilm activity. As we had established earlier, functionalization with positively charged thiol ligands can enhance colloidal stability, biocompatibility, and antibacterial efficacy; we functionalized all targeted nanomaterials. Our results revealed that functionalized MoS2 quantum dots (F-MQDs) exhibited superior activity compared to functionalized MoS2 nanoflowers (F-MNFs) and functionalized MoS2 nanosheets (F-MNSs) against Staphylococcus aureus (SA), both drug-resistant (methicillin) and nonresistant strains. We observed very low minimum inhibitory concentration (MIC, 30 ng/mL) for F-MQDs. The observed trend in antibacterial efficacy was as follows: F-MQDs > F-MNFs ≥ F-MNSs. We explored the relevant mechanism related to the antibacterial activity where the balance between membrane depolarization and internalization plays the determining role. Furthermore, F-MQDs show enhanced anti-biofilm activity compared to F-MNFs and F-MNSs against mature MRSA biofilms. Due to the superior antibacterial and anti-biofilm activity of F-MQDs, we extended their application to wound healing. This study will help us to develop other appropriate surface modified nanomaterials for antibacterial and anti-biofilm activity for further applications such as antibacterial coatings, water disinfection, and wound healing.

3D printed PGCL@PLA/10CSPL composite scaffolds loaded with fibronectin 1 for intervertebral disc degeneration treatment

Restoration of disc height and biomechanical function is essential for intervertebral disc degeneration (IDD) treatment. Removing abnormal nucleus pulposus (NP) tissue is an important step to facilitate bony fusion during the healing process. We analyzed publicly available single-cell transcriptome data for human normal and degenerative NP to identify genes associated with NP degeneration. A novel poly(glycolide-co-caprolactone)@polylactide (PLA)-b-aniline pentamer (AP)-b-PLA/chitosan-ϵ-polylysine (PGCL@1PAP/10CSPL) scaffold with good biocompatibility and electroactivity was designed and fabricated as an implant for IDD treatment using 3D printing technology. The PGCL@1PAP/10CSPL scaffold exhibited superior hydrophilicity, mechanical properties, cytocompatibility, and antibacterial activity compared to PGCL. Fibronectin 1 (FN1), identified from single-cell transcriptome analysis, was loaded into the PGCL@1PAP/10CSPL scaffold to accelerate the abnormal NP degeneration.In vitroandin vivoexperiments indicated that the PGCL@1PAP/10CSPL-FN1 scaffold enhanced osteogenic differentiation, promoted angiogenesis, and facilitated the removal of damaged disc tissue. This study introduces a novel implant system with desirable mechanical strength and unique bone-promoting and vascularizing properties for lumbar interbody fusion in IDD treatment.

Phytochemical profiling and fractionation of Helianthemum lippii extract versus silver nanoparticle-modified extract: assessment of photoprotective, anti-hemolytic, antibacterial, and anti-inflammatory properties

IntroductionThis study investigates the synthesis of silver nanoparticles (Ag NPs) using Helianthemum lippii extract and evaluates their photoprotective, anti-hemolytic, antibacterial, and anti-inflammatory properties compared to various extract fractions, including total aqueous extract (AE), flavonoid monoglycosides (FMG), flavonoid diglycosides/triglycosides (FDG/FTG), tannins (TN), and anthocyanins (AC). Helianthemum lippii is rich in bioactive compounds such as caffeic acid, p-coumaric acid, and gallic acid, known for their therapeutic potential. This study aims to determine whether embedding these phytochemicals into Ag NPs enhances their biomedical applications compared to the natural extract fractions.MethodsAg NPs were synthesized using Helianthemum lippii extract through a green synthesis approach, and their physicochemical properties, including size and morphology, were characterized. High-performance liquid chromatography (HPLC) was used to identify key phytochemicals in the various extract fractions. Biological assays were conducted to assess photoprotective efficacy (sun protection factor, SPF), antibacterial activity (minimum inhibitory concentration, MIC), anti-inflammatory potential (percentage inhibition), and hemolytic properties, with sodium dodecyl sulfate (SDS) serving as a control.ResultsHPLC analysis confirmed the presence of bioactive compounds, including caffeic acid, p-coumaric acid, and gallic acid, in the AE extract. The Ag NPs were spherical with an average diameter of 35 nm and had phytochemicals adsorbed on their surface. The AC fraction demonstrated the highest SPF (28.27), followed by TN (27.99), AE (23.20), and Ag NPs (22.50), while FMG exhibited a moderate SPF (19.39) compared to the commercial sunscreen Avene® (40.00). Ag NPs exhibited superior antibacterial activity with MIC values of 0.2 mg/mL against Pseudomonas aeruginosa and 0.4 mg/mL against Bacillus subtilis, outperforming AE, which had a MIC of 2.81 mg/mL. Anti-inflammatory assays showed that Ag NPs achieved 79.8% inhibition at 400 μg/mL, surpassing AE (71.75%) and TN (67.9%), and were comparable to diclofenac (72.63%). Hemolysis assays revealed that Ag NPs induced only 1.35% hemolysis, lower than AE (1.91%) and significantly below SDS (90.48%).DiscussionThe findings demonstrate that Helianthemum lippii-derived Ag NPs exhibit enhanced antibacterial, anti-inflammatory, and anti-hemolytic properties compared to the extract fractions. While the SPF of Ag NPs was slightly lower than the AC and TN fractions, their superior multifunctional bioactivities underscore their potential for various biomedical applications. The integration of phytochemicals into Ag NPs significantly enhances their therapeutic efficacy, making them promising candidates for advanced pharmaceutical formulations and topical protective agents.

Synthesis and Antibacterial Activity of Azetidinone and Thiazolidinone Derivatives of 1-(1´,3´-thiazol-4´-yl)-amino-2-phenyl-4- cyclohexylideneimidazol-5-one

5-one (10-14) and 1-[{2´-(2˝-substitutedaryl-4˝-thiazolidinon-3˝-yl)-1´,3´-thiazol-4´-yl}-amino-2-phenyl-4-cyclohexylideneimidazol]-5 one (15-19) have been synthesized from 1-[{2´-(substitutedarylidenylimino)-1´,3´-thiazol-4´-yl}-amino-2-phenyl-4-cyclohexylidene imidazol]-5-one (5-9). All these compounds of the present series have also been screened in vitro for their antibacterial activity against various strains of bacteria. Substantial results were obtained. Compound 11 showed superior antibacterial activity against Klebsiella pneumoniae ATCC 10031 with MIC 0.781 µg/ml. The structure of these compounds has been elucidated by IR, 1H-NMR, Mass spectral and elemental (C, H, N) analysis.

Assessment of CPME as Sustainable Low VOC Alternative to Hexane: Optimization of Extraction Efficiency and Bioactive Compound Yield from Fenugreek Seed Oil Using Computational and Experimental Methods.

This study investigates the performance of cyclopentyl methyl ether (CPME) in the extraction of fenugreek seed oil, aiming to replace the conventionally used hexane. The efficiency of this alternative solvent was evaluated first through in silico methods (based on Hansen Solubility Parameters (HSPs) and Conductor-like Screening Model for Real Solvent (COSMO-RS) simulations), followed by experimental studies. Solubility computational predictions analysis revealed that CPME exhibits superior solvation power compared to hexane. Experimentally, CPME demonstrated a significantly higher oil yield (7.23%) compared to hexane (4.25%) and a better retention of beneficial unsaturated fatty acids than hexane. Additionally, the physicochemical properties of oils extracted with CPME showed enhanced oxidative stability, sterol, tocopherol, and phenolic contents, leading to superior antioxidant and antibacterial activities. Importantly, CPME's low volatile organic compound (VOC) emissions further establish it as a more sustainable and environmentally friendly alternative to hexane, aligning with contemporary goals of reducing harmful emissions in extraction processes. Thus, this paper highlights the functional advantages of CPME, focusing on its efficiency, selectivity, and enhanced retention of bioactive compounds, positioning it as a superior extraction solvent for fenugreek seed oil compared to hexane.

Optimized MoS2/SnS2@AC nanocomposites for superior visible light-driven pollutant degradation and antibacterial activity

Optimized MoS2/SnS2@AC nanocomposites for superior visible light-driven pollutant degradation and antibacterial activity