Significant Antibacterial Potential Research Articles

Synthesis and antibacterial effects of silver nanoparticles (AgNPs) against multi-drug resistant bacteria.

The emergence of the global problem of multi-drug resistant bacteria (MDR) is closely related to the improper use of antibiotics, which gives birth to an urgent need for antimicrobial innovation in the medical and health field. Silver nanoparticles (AgNPs) show significant antibacterial potential because of their unique physical and chemical properties. By accurately regulating the morphology, size and surface properties of AgNPs, the antibacterial properties of AgNPs can be effectively enhanced and become a next generation antibacterial material with great development potential. The detection of the inhibitory effect of AgNPs on MDR provides more possibilities for the research and development of new antimicrobial agents. Promote the formation of AgNPs by redox reaction; determine the minimum inhibitory concentration (MIC) of AgNPs to bacteria by broth microdilution method; evaluate the killing efficacy of AgNPs against multi-drug-resistant bacteria by plate counting; evaluate the inhibitory effect of AgNPs on biofilm construction by crystal violet staining; study the drug resistance of bacteria by gradually increasing the concentration of AgNPs; and detect the toxicity of AgNPs to cells by CCK-8 method. AgNPs has a significant bactericidal effect on a variety of drug-resistant bacteria. After exposure to AgNPs solution for 12 hours, the number of E. coli decreased sharply, and S. aureus was basically eliminated after 16 hours. In particular, AgNPs showed stronger inhibition against Gram-negative bacteria. In addition, AgNPs can effectively hinder the formation of bacterial biofilm, and its inhibitory effect increases with the increase of AgNPs solution concentration. When AgNPs is used for a long time, the development of bacterial resistance to it is slow. From the point of view of safety, AgNPs has no harmful effects on organisms and has biosafety. AgNPs can inhibit MDR, and the bacteriostatic ability of Gram-negative bacteria is higher than that of Gram-positive bacteria. It can also inhibit the formation of bacterial biofilm, avoid drug resistance and reduce cytotoxicity.

Medicinal Efficacy of Tinospora cordifolia, Caesalpinia bonduc and Quercus infectoria Extracts

Medicinal plants have therapeutic value because of the chemical substances present in them. This study was performed to explore the antibacterial and antioxidant potential of three medicinally important plants, such as Caesalpinia bonduc (karanjuwa), Tinospora cordifolia (Giloy), and Quercus infectoria (Majuphal) extract; that are locally used for the cure of various diseases, particularly dengue fever. To study the anti-bacterial, phytochemical and antioxidative potential of these plants, plant extracts were made in ethanol, methanol, and ethyl acetate. Antibacterial assay revealed that all the selected plant extracts of C. bonduc, T. cordifolia, and Q. infectoria variably inhibited the growth of test bacterial strains. The maximum antibacterial activity observed for the ethyl acetate extract of T. cordifolia was against Bacillus (41 mm) and Pseudomonas (38 mm). Phytochemical analysis of extracts of C. bonduc, T. cordifolia, and Q. infectoria revealed the presence of alkaloids, quinones, flavonoids, phenols, and reducing sugars. Antioxidative analysis of the extracts of C. bonduc, T. cordifolia, and Q. infectoria, as revealed by the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay (66%, 62% and 77%), phosphomolybdate (480, 520 and 490 µg/ml), showed ferric reducing antioxidant power (FRAP) assay (266%, 371% and 265%), and total flavonoid content (75%, 170% and 155%) assay. Due to significant antibacterial and antioxidant potential, the extract of T. cordifolia was subjected to Thin-layer chromatography (TLC) analysis that confirmed the presence of different bioactive components in the extract of T. cordifolia (Giloy). Gas Chromatography-Mass spectrophotometry (GCMS) analysis of the bioactive fractions revealed Phthalic acid and Benzene acetic acid as the compounds responsible for imparting good antibacterial and antioxidative potential to the ethyl acetate extract of T. cordifolia. These findings highlight the potential of T. cordifolia as a valuable medicinal plant for the development of future antimicrobial drugs.

Biofilm microenvironment-activated multimodal therapy nanoplatform for effective anti-bacterial treatment and wound healing

Antimicrobial drug development faces challenges from bacterial resistance, biofilms, and excessive inflammation. Here, we design an intelligent nanoplatform utilizing mesoporous silica nanoparticles doped with copper ions for loading copper sulfide (DM/Cu2+-CuS). The mesoporous silica doped with tetrasulfide bonds responds to the biofilm microenvironment (BME), releasing Cu2+ions, CuS along with hydrogen sulfide (H2S) gas. The release of hydrogen sulfide within 72 h reached 793.5 µM, significantly higher than that observed with conventional small molecule donors. H2S induces macrophages polarization towards the M2 phenotype, reducing inflammation and synergistically accelerating endothelial cell proliferation and migration with Cu2+ions. In addition, H2S disrupts extracellular DNA within biofilms, synergistically photothermal enhanced peroxidase-like activity of CuS to effectively eradicate biofilms. Remarkably, DM-mediated consumption of endogenous glutathione enhances the anti-biofilm activity of H2S and improves oxygen species (ROS) destruction efficiency. The combination of photothermal therapy (PTT), chemodynamic therapy (CDT), and gas treatment achieves sterilization rates of 99.3 % and 99.6 % against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively, in vitro under 808 nm laser irradiation. Additionally, in vivo experiments demonstrate a significant biosafety and antibacterial potential. In summary, the H2S donor developed in this study exhibits enhanced biocompatibility and controlled release properties. By integrating BME-responsive gas therapy with antibacterial ions, PTT and CDT, a synergistic multimodal strategy is proposed to offer new therapeutic approaches for wound healing. Statement of significanceThe advanced DMOS/Cu2+-CuS (DMCC) multimodal therapeutic nanoplatform has been developed for the treatment of drug-resistant bacterial wound infections and has exhibited enhanced therapeutic efficacy through the synergistic effects of photothermal therapy, chemodynamic therapy, Cu2+ions, and H2S. The DMCC exhibited exceptional biocompatibility and could release CuS, Cu2+, and H2S in response to elevated concentrations of glutathione within the biofilm microenvironment. H2S effectively disrupted the biofilm structure. Meanwhile, peroxidase activity of CuS combined with GSH-mediated reduction of Cu2+ to Cu+ generated abundant hydroxyl radicals under acidic conditions, leading to efficient eradication of pathogenic bacteria. Furthermore, both H2S and Cu2+ could modulate M2 macrophages polarization and regulate immune microenvironment dynamics. These strategies collectively provided a novel approach for developing antibacterial nanomedical platforms.

Argyreia nervosa-driven biosynthesis of Cu-Ag bimetallic nanoparticles from plant leaves extract unveils enhanced antibacterial properties.

Our study specifically explores the biosynthesis of copper-silver bimetallic nanoparticles (Cu-Ag BMNPs) using Argyreia nervosa (AN) plant leaf green extract as a versatile agent for capping, reducing, and stabilizing. This biosynthesis method is characterized by its simplicity and cost-effectiveness, utilizing silver nitrate (AgNO3) and cupric oxide (CuO) as precursor materials. Our comprehensive characterization of the Cu-Ag BMNPs, employing techniques such as X-ray diffraction (XRD), UV-Vis spectrometry, scanning electron microscopy (SEM), Zetasizer, and Fourier transformed infrared spectrometry (FTIR). FTIR analysis reveals biofunctional groups and chemical bands, while SEM and XRD analyses provide morphological and structural details. To evaluate the antimicrobial properties of the Cu-Ag BMNPs, we conducted disc diffusion and minimum inhibitory concentration (MIC) assays against Escherichia coli (E. coli), with results compared to the standard gentamicin antibiotic. It is observed that the 2% and 5% CuO concentrations of AN Cu-Ag BMNPs exhibit substantial antibacterial activity in comparison to AN extract when tested on EPEC. Among these, the Cu-Ag BMNPs at a 2% concentration demonstrate higher antibacterial activity, potentially attributed to the enhanced dispersion of BMNPs facilitated by the lower CuO doping concentration. These two assays showcased the improved antimicrobial activity of Cu-Ag BMNPs, highlighting their synergistic effect, characterized by high MIC values and a broad zone of inhibition in the disc diffusion tests against E. coli. These results emphasize the significant antibacterial potential of the synthesized BMNPs, with a medicinal plant AN leaf extract playing a pivotal role in enhancing antibacterial activity.

Enhancement efficacy of omeprazole by conjugation with silver nanoparticles as a urease inhibitor

Abstract Omeprazole, a proton pump inhibitor, is used for gastric and duodenal ulcers, gastroesophageal reflux disease, Helicobacter pylori infection, etc. Current research is based on the loading of omeprazole on surface silver nanoparticles by chemical method. The appearance of an absorption peak at 421 nm confirmed the synthesis of nanoparticles. The FT-IR further confirmed the conjugation of functional groups present in omeprazole moiety with silver. The size and morphology were elucidated by transmission electron microscopy and X-ray diffraction which revealed a spherical shape with an average particle size of 16–20 nm. To know enhancement in their efficacy, the omeprazole-loaded nanoparticles were evaluated against antibacterial, urease inhibition, and antioxidant activities. Nanoparticles showed significant antibacterial potential against Staphylococcus aureus and Escherichia coli with 12 ± 0.41 and 13.6 ± 1.02 mm zones of inhibition, respectively. Almost 2.43 times enhanced urease inhibitory activity was found for nanoparticles (IC50 = 2.17 ± 0.10 µg·mL−1) as compared to omeprazole (IC50 = 5.28 ± 0.14 µg·mL−1). The radical scavenging activity of nanoparticles also increased significantly. The synthesized nanoparticles were docked in the active site of urease to investigate their binding mode. Due to excellent urease and bacterial inhibition, these nanoparticles can be used for ulcers.

Bacterial cellulose-turmeric powder composites as potential therapeutic wound dressings

Bacterial cellulose (BC) has emerged as a promising biomaterial for rapid wound healing and tissue regeneration due to its excellent liquid absorbing and biocompatible properties. However, its lack of therapeutic properties restricts its applicability as a wound dressing. The current study was undertaken to develop bacterial cellulose-turmeric powder (BC-TP) composite films as wound dressing materials that combine the therapeutic properties of turmeric powder (TP) with the unique structural, physicochemical, and biological properties of BC. FTIR and SEM showed that TP was successfully impregnated into BC films using an ex-situ approach. Swelling and water release rate studies revealed that the composite films produced had high-water uptake and retention capacities. Antibacterial investigations using gram-positive and -negative species demonstrated the significant antibacterial potential of TP when incorporated into a BC matrix. Toxicity testing confirmed the non-cytotoxic nature of BC-TP composite films, while biocompatibility investigations demonstrated that fibroblast cells attached and proliferated effectively on BC films treated with TP. Furthermore, BC-TP composites promoted tissue regeneration, hair growth, and wound healing. BC composites exhibited over 90% wound closure by the 7th day, whereas untreated wounds demonstrated only approximately 24% closure during the same period. The study shows that the manufactured BC-TP composite films offer starting points for the development of alternative standard wound dressing systems.

Evaluation of Phytochemicals and Antibacterial Usefulness of Citrus Limon & Cicer Arietinum in Synergistic Effect with Antibiotics Against Clinically Important Bacteria

Background: The emergence of antibiotic resistance necessitates exploring alternative treatments, including natural plant extracts. Lemon juice (Citrus limon) and chickpea (Cicer arietinum) seed aqueous extract, known for their medicinal properties, are investigated for their potential antibacterial effects. Objective: This study aimed to assess the antibacterial efficacy of lemon juice and chickpea seed aqueous extract, individually and in combination with antibiotics, against various pathogenic bacterial strains. Methods: Aqueous and ethanolic extracts of C. limon and C. arietinum were prepared. Antibacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Pseudomonas aeruginosa, sourced from the University of Education, Lahore, was assessed using the disc diffusion method. Extract concentrations of 5%, 10%, 20%, and 40% were tested. Phytochemical analysis identified active compounds in the extracts. Antibacterial efficacy was quantified by measuring inhibition zones in millimeters. Results: Lemon juice showed dose-dependent antibacterial activity with inhibition zones up to 19.8±0.088 mm at 40% concentration. Chickpea extract was effective against S. aureus with a maximum inhibition of 14±0.577 mm at 40%. Combined treatments enhanced antibacterial effects, particularly against S. aureus, with a combination of lemon juice, chickpea extract, and antibiotics yielding an inhibition zone of 20.1±0.058 mm at the highest concentration. In contrast, chickpea extract alone showed no activity against E. coli, K. pneumoniae, or P. aeruginosa. Conclusion: The study confirms the significant antibacterial potential of lemon juice across multiple bacterial strains and the specific efficacy of chickpea extract against S. aureus. The combination of these extracts with antibiotics suggests a promising avenue for augmenting antibacterial treatment strategies.

Photoinduced RhB-sensitized effect on a novel AgI/BiOCl/biochar photocatalyst to boost its photocatalytic performance for 17α-ethinyl estradiol degradation

In this study, a simple and effective strategy was developed for the synthesis of novel visible-light-active AgI/BiOCl/biochar (AgI/BiOCl/BC) photocatalysts. The addition of rhodamine B (RhB) as a sensitizer was found to considerably enhance the photocatalytic activity of AgI/BiOCl/BC toward the degradation of 17α-ethinyl estradiol (EE2). Furthermore, the incorporation of biochar (BC) into the BiOCl resulted in an increased abundance of free radicals, that could be used for degradation. Additionally, the presence of BC facilitated the separation of carriers by serving as an electron transport channel. The photocatalytic efficiency of the AgI/BiOCl/BC photocatalyst was shown to be highly effective in the degradation of EE2, the degradation efficiency of the AgI/BiOCl/BC was found to be 98.60 % after a 12-min exposure to visible light. Additionally, the photocatalytic activity increased further when RhB sensitization was performed, resulting in a remarkable elimination efficiency of 99.60 % for EE2 after only 4 min of photocatalysis. RhB could not only provide photosensitivity but also degrade along with EE2 as a pollutant, which can be used for the treatments of dyes and EE2 wastewater. The results of photocatalysis investigations indicated that AgI/BiOCl/BC could degrade various dyes, including methyl orange (MO), methylene blue (MB), and congo red (CR). Through the introduction of Ag-based materials, the obtained AgI/BiOCl/BC photocatalyst exhibited significant antibacterial potential against Staphylococcus aureus and Escherichia coli, with antibacterial rates of 99.94 % and 99.99 %, respectively. The cyclic experiment demonstarted that AgI/BiOCl/BC exhibited excellent stability and recyclability. Furthermore, the potential photocatalytic mechanism and degradation pathway were suggested through a combination of experimental findings and theoretical investigations. The obtained AgI/BiOCl/BC photocatalyst is a multifunctional photocatalyst with excellent performance in photocatalytic degradation and sterilization. This photocatalyst is expected to be applied to the treatment of complex pollutant water in the environmental field.

Inhibition of foodborne bacterial pathogens using novel mycosynthesized cobalt nano ferrites and CoFe2O4 nanoparticles anchored on functionalized multi-walled carbon nanotube bionanocomposites

Cobalt nanoferrites and their nanocomposites have attracted significant attention because of their numerous applications. This study reports a novel mycosynthesis of cobalt ferrite nanoparticles (CoFe2O4 NPs) and cobalt ferrite/functionalized multi-walled carbon nanotube (CoFe2O4/fMWCNT) bionanocomposites using the mycelial cell-free filtrate (MCFF) of Aspergillus sojae (KACC 45023). The reaction of A. sojae MCFF with ferric nitrate nonahydrate and cobalt chloride hexahydrate resulted in changing the colorless solution of the MCFF to reddish-brown color and formation of a reddish-brown precipitate, indicating the mycosynthesis of CoFe2O4 NPs. The mycosynthesized CoFe2O4 NPs were biologically anchored onto fMWCNTs using A. sojae MCFF, yielding CoFe2O4/fMWCNT bionanocomposites. Physicochemical and morphological properties of the mycosynthesized CoFe2O4 NPs and CoFe2O4/fMWCNT bionanocomposites were characterized using X-ray diffraction, Fourier-transform infrared spectroscopy, dynamic light scattering, zeta potential analysis, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, field-emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy. The mycosynthesized CoFe2O4 NPs and CoFe2O4/fMWCNT bionanocomposites showed significant antibacterial potential against three foodborne pathogenic bacteria, Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus using an agar-well diffusion assay. The morphological structures of the bacterial cells examined by FESEM revealed changes in the intact bacterial cell structures into misshapen and twisted bacterial cells, as well as deposition of the mycosynthesized CoFe2O4 NPs and CoFe2O4/fMWCNT bionanocomposites on the bacterial cells. The present study reveals the high potential of fungi as valuable bionanofactories for the mycosynthesis of ferrite-based NPs and their bionanocomposites as eco-friendly biosynthesis routes.

Studying the Potential of Copper Nanoparticles Synthesized from Staphylococcus aureus against Drug-Resistant Bacteria

Copper nanoparticles (CuNPs) have gained a lot of interest due to their tendency to combat various bacterial strains, making them potential candidates against antibiotic resistant bacteria. Green synthesis of CuNPs eradicates the potential drawbacks of other traditional methods such as high cost, toxic chemicals and adverse conditions. The objectives of current study include the preparation of CuNPs from the culture supernatant of Staphylococcus aureus and the analysis of antibacterial potential of prepared CuNPs. The synthesis of CuNPs from the culture supernatant of Staphylococcus aureus was carried out under various optimization conditions including pH, temperature, incubation time, and concentration of salt. This research study focuses on the preparation of fine and well defined CuNPs by the reduction of Cu2+ ions using the culture supernatant of clinical isolate of Staphylococcus aureus as the feasible and cost effective method. The prepared nanoparticles were characterized through various techniques including Ultraviolet Visible Spectrophotometry, Dynamic Light Scattering and Scanning electron microscopy. The prepared copper nanoparticles were studied for their antibacterial potential by the Agar Well Method against drug resistant and drug sensitive bacteria. The surface plasmon resonance of copper nanoparticles was maximum around the visible range wavelength of 380 nm which is the characteristic absorbance peak of copper nanoparticles while the dynamic light scattering analysis recorded the maximum percentage intensity of particle size distribution around 295 nm. SEM analysis showed the amorphous nature of particles with no distinct size and shape. CuNPs showed significant antibacterial potential against drug resistant Salmonella typhimurium with 29mm zone of inhibition and against drug sensitive Bacillus subtillis with 25mm zone of inhibition. The antibacterial potential of copper nanoparticles was found to be appreciable against drug resistant Salmonella typhimurium, Staphylococcus epidermis and Staphylococcus aureus.

Fabrication and evaluation of vitamin doped Zno/AgNPs nanocomposite based wheat gluten films: a promising findings for burn wound treatment

Burn wound treatment remains a significant issue in wound care management especially when multidrug resistant bacterial infection and accumulation are present. Delayed wound healing is mostly due to ineffectiveness of commercially available wound dressings that protects the wound but less efficient in healing perspective. Therefore, nano-based wound dressing might be efficient solution for wound healing management. The present study reports the fabrication and evaluation of zinc oxide (ZnO) or silver nanoparticles (Ag NPs) capped with vitamin A or E nanocomposite that were incorporated in wheat gluten (WG) films. The chemical structure, phase purity, and morphological features confirmed the successful coating of NPs by vitamins A and E and their interaction with WG during film casting. The maximum swelling response was observed by NPs vitamin composite WG films than control films while slow release of vitamins and NPs from films was observed up to 24 h. WG films either carrying ZnO or Ag NPs, and vitamin A or E demonstrated significant antioxidant and antibacterial potential. The NPs-vitamin composite loaded WG films showed wound contraction within 14 days during in vivo burn wound healing experiments on mice model. The rates of wound healing, re-epithelialization, collagen deposition with fibroblast regeneration, adipocytes, and hair follicle development were observed through visual and histopathological examination. The study reveals that vitamin A or E doped ZnO or Ag NPs fabricated in WG can be efficiently used against burn wounds due to their physiochemical and biological properties. Furthermore the biocompatible nature and biodegradable potential make the films more prone to mankind maneuver for initial protection and healing remedy.

Anatase-cellulose acetate for reinforced desalination membrane with antibacterial properties

This study aimed to prepare antifouling and highly mechanical strengthening membranes for brackish and underground water desalination. It was designed from cellulose acetate (CA) loaded anatase. Anatase was prepared from tetra-iso-propylorthotitanate and carboxymethyl cellulose. Different concentrations of anatase (0.2, 0.3, 0.5, 0.6, 0.7, and 0.8)% were loaded onto CA during the inversion phase preparation of the membranes. The prepared membranes were characterized using Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM & EDX), mechanical properties, swelling ratio, porosity determination, and ion release. The analysis confirmed the formation of anatase on the surface and inside the macro-voids of the membrane. Furthermore, anatase loading improved the CA membrane’s mechanical properties and decreased its swelling and porosity rate. Also, CA-loaded anatase membranes displayed a significant antibacterial potential against Gram-positive and Gram-negative bacteria. The results showed that the salt rejection of the CA/anatase films as-prepared varies considerably with the addition of nanomaterial, rising from 46%:92% with the prepared membranes under the 10-bar operation condition and 5 g/L NaCl input concentration. It can be concluded that the prepared CA-loaded anatase membranes have high mechanical properties that are safe, economical, available, and can stop membrane biofouling.

Design, synthesis, and unraveling the antibacterial and antibiofilm potential of 2-azidobenzothiazoles: insights from a comprehensive in vitro study.

The present study reports the synthesis of 2-azidobenzothiazoles from substituted 2-aminobenzothiazoles using sodium nitrite and sodium azide under mild conditions. All the synthesized compounds were examined for their antibacterial activity against Gram (+) bacteria, Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 51299), Bacillus cereus (ATCC 10876) and Gram (-) bacteria, Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 10145), Klebsiella pneumonia (ATCC BAA-2146)and clinical isolates of Gram (+) Methicillin Resistant S. aureus (MRSA) and Multi Drug Resistant E. coli. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values by broth dilution method revealed that compound 2d exhibited significant antibacterial potential against E. faecalis and S. aureus with MIC of 8μg/mL, while other synthesized compounds had only moderate effects against all the tested species. The compound significantly inhibited the biofilm formation of the bacterial strains below its MIC. The selective cytotoxicity of Compound 2d towards bacterial cells was evidenced on extended exposure of Human Embryonic Kidney-293 cell line to higher concentrations of the compound. Hence, the present study confirmed that compound 2d can be a potential drug candidate for future development as an antibacterial drug.

Chemical composition, antimicrobial, antioxidant and anti-cancer activities of Nepeta deflersiana Schweinf. Ex Hedge and Marrubium vulgare L. essential oils: a comparative study

This work focuses on evaluating the chemical composition, biological potency and in silico computational studies of selected identified molecules in the essential oils obtained from Nepeta deflersiana (Lamiaceae) and Marrubium vulgare (Lamiaceae) plants. The essential oils were extracted using Clevenger-type system and analyzed by gas chromatography-based techniques (GC-FID and GC-MS) using a HP-5MS column. Twenty constituents were identified in Nepeta deflersiana essential oil (NDEO) whereas forty-three were identified in Marrubium vulgare essential oil (MVEO) representing 99.55% and 94.75% of the total essential oil composition, respectively. 4aα,7α,7aα Nepetalactone was the major component in both NDEO (77.79%) and MVEO (63.67%) and first time reported in Marrubium genus by our group. The antioxidant activity has been determined using DPPH, TEAC and FRAP methods and expressed as μmol Trolox equivalent/g. All the spectrophotometric assays proved the strong radical scavenging and reducing power of MVEO. The antimicrobial activities revealed moderate to significant antibacterial potential and no inhibitory effect was observed against C. albicans. NDEO showed the highest effectiveness against S. pneumoniae (24 mm zone of inhibition, MIC 25 μg/mL). Cytotoxicity assessment against two breast cancers (MCF-7 and MDA-MB-231) and one prostate cancer cell (PC-3) revealed that MVEO was more cytotoxic than NDEO to the tested breast cell lines (IC50 = 30.11 for MCF-7 and 68.25 μg/mL for MDA-MB-231) while moderately inhibited prostate cancer cells (IC50 = 135.60 μg/mL). In silico computation study for selected ingredients suggested that they have drug-likeness properties.

Antimicrobial Potential of Aqueous Extract of Giant Sword Fern and Ultra-High-Performance Liquid Chromatography-High-Resolution Mass Spectrometry Analysis.

Vibriosis and parasitic leech infestations cause the death of various farmed fish, such as groupers, hybrid groupers, sea bass, etc., in Malaysia and other Southeast Asian countries. In the absence of natural control agents, aquaculture operators rely on toxic chemicals to control Vibrio infections and parasitic leeches, which can have a negative impact on the environment and health. In the present study, we investigated the antivibrio and antiparasitic activities of the aqueous extract of giant sword fern (GSF) (Nephrolepis biserrata, Nephrolepidaceae, locally known as "Paku Pedang") against four Vibrio spp. and the parasitic leech Zeylanicobdella arugamensis, as well as its metabolic composition using the ultra-high-performance liquid chromatography-high-resolution mass spectrometry system (UHPLC-HRMS). The data show that the aqueous extract of GSF at a concentration of 100 mg/mL exhibits potent bactericidal activity against V. parahaemolyticus with a zone of inhibition of 19.5 mm. In addition, the extract showed dose-dependent activity against leeches, resulting in the complete killing of the parasitic leeches within a short period of 11-43 min when tested at concentrations ranging from 100 to 25 mg/mL. The UHPLC-HRMS analysis detected 118 metabolites in the aqueous extract of GSF. Flavonoids were the primary metabolites, followed by phenolic, aromatic, fatty acyl, terpenoid, vitamin and steroidal compounds. Notably, several of these metabolites possess antibacterial and antiparasitic properties, including cinnamaldehyde, cinnamic acid, apigenin, quercetin, cynaroside, luteolin, naringenin, wogonin, 6-gingerol, nicotinamide, abscisic acid, daidzein, salvianolic acid B, etc. Overall, our study shows the significant antibacterial and antiparasitic potential of the GSF aqueous extract, which demonstrates the presence of valuable secondary metabolites. Consequently, the aqueous extract is a promising natural alternative for the effective control of Vibrio infections and the treatment of parasitic leeches in aquaculture systems.

Antibacterial Properties of Methanolic Leaf Extracts of Melia azedarach L. against Gram-Positive and Gram-Negative Pathogenic Bacteria.

Melia azedarach L., a Meliaceae family tree, is widely used in traditional folkloric medicine for its pharmaceutical properties. In the present study, we investigated the phytochemical composition of four methanolic leaf extracts of M. azedarach of various origins (Algeria and Tunisia) using high-performance liquid chromatography (HPLC). The antibacterial efficacy and mechanisms of action against Gram-positive and Gram-negative pathogenic microorganisms were then evaluated. Our findings revealed a presence of phenolic acids and flavonoids, such as gallic acid, chlorogenic acid, caffeic acid, hyperoside, isoquercetin, quercetin, and isorhamnetin both in Algerian and Tunisian localities, with an abundance of phenolic acids compared to flavonoids. Additionally, the studied extracts exhibit a broad spectrum of antibacterial activities, with MIC values ranging from 31.25 mg/mL to 125 mg/mL. Methanolic leaf extracts of M. azedarach from Algeria exhibited more potent biofilm eradication, with a percentage of inhibition reaching 72.17% against the S. aureus strain. Furthermore, inhibitory concentrations of tested substances, particularly the extract from the Relizane area, were capable of disrupting the membrane integrity of the treated bacteria as well as producing oxidative stress through ROS generation. Likewise, our results reveal that plant extract induces lipid peroxidation by raising MDA levels in comparison to untreated cells, particularly with the plant extract of Blida. M. azedarach extracts also reduced the synthesis of antioxidant enzymes (CAT and SOD). Our findings illustrate that M. azedarach remains a plant with significant antibacterial potential and distinct mechanisms of action that are closely related to the origins of this specimen.

Repurposing Amphotericin B: anti-microbial, molecular docking and molecular dynamics simulation studies suggest inhibition potential of Amphotericin B against MRSA

Amphotericin B (AMPH) is an anti-fungal drug and this study, for the first time as best of our knowledge, reports the repurposing of the Amphotericin B. The drug was found to show significant antibacterial potential revealed by antimicrobial screening, molecular docking, and mode of action analysis targeting Penicillin Binding Protein 2a (PBP 2a protein) which is target of β-lactam drugs and is involved in cell wall synthesis. Mode of action analysis showed the drug to have hydrophobic and hydrophilic interactions with both C-terminal, trans-peptidase and non-penicillin binding domain of the protein. Additionally, to evaluate the impact of ligand binding on the protein's conformational dynamics, molecular dynamics (MD) simulations were used. Comparative Dynamical flexibility (RMSF) and Dynamics Cross Correlation (DCCM) followed by MD simulations revealed the complex formation significantly effecting structural dynamics of the enzyme significantly in the non-penicillin binding domain (327–668) and slightly in trans peptidase domain. Radius of gyration assessment further showed ligand binding also decreasing over all compactness of protein. Secondary structure analysis indicated the complex formation changing the conformational integrity in non-penicillin binding domain. Hydrogen bond analysis and MMPBSA, free energy of calculations followed by MD simulations, also complemented the antimicrobial and molecular docking revelations suggesting Amphotericin B to have substantial antibacterial potential.

Biogenic Nanoparticles: Synthesis, Characterization, and Biological Potential of Gold Nanoparticles Synthesized using Lasiosiphon eriocephalus Decne Plant Extract.

Recent advancements in biomedicine have revolutionized nanomedicine as a therapeutic moderator in the management of both infectious and noninfectious diseases. In the current study we demonstrated biosynthesis of gold nanoparticles using aqueous leaf extract of Lasiosiphon eriocephalus as a capping and reducing agent and evaluation of their antioxidant, antibacterial, and anticancer properties. The biosynthesized LE-AuNPs were characterized by UV-Vis spectrophotometry, SEM, TEM, XRD, FTIR, DLS, and Zeta potential analysis. The antibacterial activity was checked by a minimum inhibitory concentration assay. The anticancer potential of biogenic LE-AuNPs was checked by cytotoxicity and genotoxicity assay against HeLa and HCT-15 cells. The characteristic surface plasmon resonance peak of the colloidal solution at 538 nm by UV-Vis spectrum confirmed the formation of LE-AuNPs in the solution. The SEM, TEM, and XRD revealed 20-60 sized hexagonal and crystalline LE-AuNPs. The LE-AuNPs displayed significant inhibition potential against DPPH and ABTS radicals in vitro. The LE-AuNPs demonstrated significant antibacterial potential. The results of cytotoxicity interpreted that biogenic gold nanoparticles exhibited strong dose and time-dependent cytotoxicity effect against selected cancer cell lines where IC50 of LE-AuNPs required to inhibit the growth of HeLa cells after 24 h and 48 h exposure were 5.65± 0.69 μg/mL and 4.37±0.23 μg/mL respectively and that of HCT- 15 cells was 6.46 ± 0.69 μg/mL and 5.27 ± 0.34 μg/mL, 24h and 48h post-exposure respectively. Findings from this study revealed that gold nanoparticles synthesized using L. eriocephalus, showed remarkable antioxidant, antimicrobial, and extensive cytotoxicity and genotoxicity activities.

Green synthesis, characterization, and antibacterial activity of Citrus lanatus based silver nanoparticles.

Due to their enhanced and unique physicochemical characteristics, such as their minimal dimensions, large surface area compared to their mass and increased reactivity, nanomaterials hold promise in the field of antibacterial therapy. The aim of this study is to evaluate the method for Green Synthesis, Characterization of Citrus lanatus pulp, rind, and seed-based Silver Nanoparticles, and study its antibacterial activity against common oral microorganisms. Green synthesis of nanoparticles was formulated using the extract from the rind, seed, and pulp of Citrullus lanatus and silver nitrate extract. The extract was stirred in a magnetic stirrer for 24 hours, and centrifugation was done at 8000 rpm for 10 minutes. The synthesized nanoparticles were characterized and utilized for the antibacterial study. The characterization was done using UV-visible light spectroscopy, and antibacterial activity was assessed using the well diffusion method and measuring the zone of inhibition. The nanoparticles synthesized were characterized using UV-visible spectroscopy, and the spectroscopic analysis confirmed the formation of silver particles in this study. At 450 nm, a sharp peak was observed, which correlated to the SPR band of the particles. The results showed that the zone of inhibition assessed was comparable to the standard. From this study it can be concluded that silver nanoparticles (AgNPs) produced by green synthesis from Citrullus lanatus showed significant antibacterial potential against common oral microflora.

Antibiotic‐Derived Carbon‐Nanodot‐Decorated Hydrogel for Reactive Oxygen Species‐Enhanced Anti‐Infection Through Biofilm Damage

AbstractIrreversible bacterial resistance and impenetrable biofilms have rendered conventional antibiotic therapy ineffective. Nevertheless, increasing evidence has confirmed that antibiotic carbon nanodots (CDs) exhibit potent antibacterial activity. However, the complex chemical composition of antibiotic CDs, and, hence, their antibacterial mechanism, is difficult to understand. The design of new antibiotic CDs against antibacterial resistance is an urgent requirement.In this study, kanamycin‐sulfate‐derived carbon nanodots (KCDs) are found to exhibit significant antibacterial potential with the assistance of light irradiation. Systematic analysis indicates that KCDs not only retain the active structure of kanamycin but also produce five new components modified on its surface, which are shown to inhibit the activity of Staphylococcus aureus beta‐ketoacyl‐acp synthase III (FabH) through molecular docking. Furthermore, the multifunctional hydrogels (CG‐KCDs) self‐assemble into injectable, self‐healing, and antibiofilm structures through noncovalent forces between the KCDs and cationic guar gum (CG). The results indicate that under laser, CG‐KCDs irradiation exhibits enhanced antibacterial activity in vitro by damaging bacterial biofilms in a reactive oxygen species (ROS)‐dependent manner, as determined by transcriptomics. Further, the therapeutic effects of CG‐KCDs hydrogel dressings on wound healing and tissue remodeling under laser are confirmed using an in vivo wound infection model. These results validate the potential of KCDs as efficient antibacterial agents to replace antibiotics as an anti‐infective strategy.