RESUMO
BACKGROUND: Although synthetic preservatives and antioxidants may have high antimicrobial and antioxidant activity, they are usually associated with adverse effects on human health. Currently, there is a growing interest in natural antimicrobial and antioxidant agents. This study aimed to evaluate the antimicrobial activity of two medicinal plant extracts and one active compound. Olive leaf extracts (0.2, 0.3, and 0.4% w/v), oleuropein (0.2, 0.4, and 0.6% w/v), thyme oil (0.1%), and oleuropein in combination with thyme oil (0.4% w/v and 0.1% v/v) were used against three bacterial strains (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) and two fungal strains (Candida albicans and Aspergillus niger). RESULTS: The use of oleuropein resulted in complete antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In this context, a reduction of 7 logs was achieved during the storage period (4 weeks). Oleuropein showed no fungal activity at low concentrations (0.2%), but Aspergillus niger was reduced by 2.35 logs at higher concentrations (0.6% w/v). Similar antibacterial and antifungal properties were observed for the olive leaf extracts. Oleuropein at a concentration of 0.4 w/v and a mixture of oleuropein and thyme at concentrations of 0.4 and 0.1 (v/v) showed strong antimicrobial activity against the studied microorganisms. CONCLUSION: Olive leaf extract, thyme oil, and oleuropein have strong antibacterial and weak antifungal properties. There was a good synergistic effect between oleuropein and thymol.
Assuntos
Antibacterianos , Antifúngicos , Glucosídeos Iridoides , Iridoides , Olea , Extratos Vegetais , Folhas de Planta , Thymus (Planta) , Thymus (Planta)/química , Glucosídeos Iridoides/farmacologia , Olea/química , Extratos Vegetais/farmacologia , Antifúngicos/farmacologia , Antibacterianos/farmacologia , Iridoides/farmacologia , Testes de Sensibilidade Microbiana , Aspergillus niger/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Óleos de Plantas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacosRESUMO
Biofilms are composed of complex multi-species in nature, potentially threatening drinking water safety. In this work, the formation of single- and multi-species fungal biofilms formed by Aspergillus niger (A. niger) and Aspergillus flavus (A. flavus), and the inactivation of mature biofilms using chlor(am)ine were firstly investigated. Results revealed that the antagonistic interaction occurred between A. niger and A. flavus. Chloramination at 20 mg/L for 30 min achieved 74.74 % and 76.04 % inactivation of A. flavus and multi-species biofilm, which were 1.69- and 1.84-fold higher than that of chlorine at the same condition. However, no significant difference was observed in the inactivation of A. niger biofilm between chlorine and monochloramine disinfection due to the lower amount of extracellular polymeric substance produced by it (p > 0.05). The inactivation of biofilm by monochloramine fitted the Weibull model well. According to the Weibull model, the monochloramine resistance of biofilm were as follows: A. flavus > multi-species > A. niger biofilm. Besides, an increase in reactive oxygen levels, damage of cell membrane, and leakage of intracellular substances in biofilms were observed after chlor(am)ination. More intracellular polysaccharides and proteins were leaked in chloramination inactivation (p < 0.05). This study provides important implications for controlling fungal biofilm.
Assuntos
Aspergillus flavus , Aspergillus niger , Biofilmes , Cloraminas , Desinfetantes , Desinfecção , Biofilmes/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Cloraminas/farmacologia , Desinfecção/métodos , Desinfetantes/farmacologia , Aspergillus flavus/efeitos dos fármacos , Microbiologia da Água , Espécies Reativas de Oxigênio/metabolismo , Purificação da Água/métodos , Farmacorresistência Fúngica/efeitos dos fármacosRESUMO
Invasive fungal infections (IFI) pose a significant health burden, leading to high morbidity, mortality, and treatment costs. This study aims to develop and characterize nanomicelles for the codelivery of posaconazole and hemp seed oil for IFI via the oral route. The nanomicelles were prepared using a nanoprecipitation method and optimized through the Box Behnken design. The optimized nanomicelles resulted in satisfactory results for zeta potential, size, PDI, entrapment efficiency, TEM, and stability studies. FTIR and DSC results confirm the compatibility and amorphous state of the prepared nanomicelles. Confocal laser scanning microscopy showed that the optimized nanomicelles penetrated the tissue more deeply (44.9µm) than the suspension (25µm). The drug-loaded nanomicelles exhibited sustained cumulative drug release of 95.48 ± 3.27% for 24 h. The nanomicelles showed significant inhibition against Aspergillus niger and Candida albicans (22.4 ± 0.21 and 32.2 ± 0.46 mm, respectively). The pharmacokinetic study on Wistar rats exhibited a 1.8-fold increase in relative bioavailability for the nanomicelles compared to the suspension. These results confirm their therapeutic efficacy and lay the groundwork for future research and clinical applications, providing a promising synergistic antifungal nanomicelles approach for treating IFIs.
Assuntos
Antifúngicos , Óleos de Plantas , Animais , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Antifúngicos/farmacologia , Antifúngicos/química , Ratos , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Óleos de Plantas/administração & dosagem , Triazóis/administração & dosagem , Triazóis/farmacocinética , Triazóis/química , Triazóis/farmacologia , Nanopartículas/química , Ratos Wistar , Candida albicans/efeitos dos fármacos , Infecções Fúngicas Invasivas/tratamento farmacológico , Aspergillus niger/efeitos dos fármacos , Micelas , Sementes/química , Liberação Controlada de Fármacos , Masculino , Portadores de Fármacos/químicaRESUMO
AIMS: In this study, the antifungal efficacy and phytotoxicity of silica coated porous zinc oxide nanoparticle (SZNP) were analyzed as this nanocomposite was observed to be a suitable platform for slow release fungicides and has the promise to bring down the dosage of other agrochemicals as well. METHODS AND RESULTS: Loading and release kinetics of tricyclazole, a potent fungicide, were analyzed by measuring surface area (SBET) using Brunauer-Emmett-Teller (BET) isotherm and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively. The antifungal efficacy of ZnO nanoparticle (ZNP) and SZNP was investigated on two phytopathogenic fungi (Alternaria solani and Aspergillus niger). The morphological changes to the fungal structure due to ZNP and SZNP treatment were studied by field emission-scanning electron microscopy. Nanoparticle mediated elevation of reactive oxygen species (ROS) in fungal samples was detected by analyzing the levels of superoxide dismutase, catalase, thiol content, lipid peroxidation, and by 2,7-dichlorofluorescin diacetate assay. The phytotoxicity of these two nanostructures was assessed in rice plants by measuring primary plant growth parameters. Further, the translocation of the nanocomposite in the same plant model system was examined by checking the presence of fluorescein isothiocyanate tagged SZNP within the plant tissue. CONCLUSIONS: ZNP had superior antifungal efficacy than SZNP and caused the generation of more ROS in the fungal samples. Even then, SZNP was preferred as an agrochemical delivery vehicle because, unlike ZNP alone, it was not toxic to plant system. Moreover, as silica in nanoform is entomotoxic in nature and nano ZnO has antifungal property, both the cargo (agrochemical) and the carrier system (silica coated porous nano zinc oxide) will have a synergistic effect in crop protection.
Assuntos
Antifúngicos , Nanocompostos , Dióxido de Silício , Óxido de Zinco , Óxido de Zinco/farmacologia , Nanocompostos/toxicidade , Dióxido de Silício/farmacologia , Dióxido de Silício/química , Antifúngicos/farmacologia , Agroquímicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Oryza/microbiologia , Oryza/crescimento & desenvolvimento , Oryza/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Porosidade , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Preparações de Ação Retardada , Espécies Reativas de Oxigênio/metabolismoRESUMO
An estimated 1.7 million fatalities and 150 million cases worldwide are attributed to fungal infections annually, that are in rise due to immunocompromised patient population. The challenges posed by traditional treatments can be addressed with the help of nanotechnology advancements. In this study, Co, Cu, and Ag-were doped into silica nanoparticles. Then the synthesized monometallic silica nanohybrids were combined to formulate heterometallic silica nanohybrids, characterized structurally and morphologically, compared, and evaluated for antifungal activity based on their individual and synergistic activity. The antifungal assays were conducted by using ATCC cultures of Candida albicans and QC samples of Trichophyton rubrum, Microsporum gypseum, and Aspergillus niger. The MIC (ranging from 49.00 to 1560.00 µg/mL), MFC (ranging from 197.00 to 3125.00 µg/mL), IC50 values (ranging from 31.10 to 400.80 µg/mL), and FICI of nanohybrids were determined and compared. Moreover, well diffusion assay was performed. ABTS assay and DPPH assay were conducted to investigate the radical scavenging activity (RSA) of nanohybrids. SEM analysis clearly evidenced the structural deformations of each fungal cells and spores due to the treatment with trimetallic nanohybrid. According to the results, the trimetallic silica nanohybrids exhibited the most powerful synergistic RSA and the most effective antifungal activity, compared to the bimetallic silica nanohybrids.
Assuntos
Antifúngicos , Candida albicans , Testes de Sensibilidade Microbiana , Dióxido de Silício , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Candida albicans/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Nanopartículas/química , Microsporum/efeitos dos fármacos , Sinergismo Farmacológico , Cobre/química , Cobre/farmacologia , Prata/farmacologia , Prata/química , ArthrodermataceaeRESUMO
Nano-biotechnology is quickly developing as an important field of modern research, generating the most promising applications in medicine and agriculture. Biosynthesis of silver nanoparticles using biogenic or green approach provide ecofriendly, clean and effective way out for the synthesis of nanoparticles. The main aim of the study was to synthesize silver nanoparticles (AgNPs) from Aspergillus niger, Aspergillus flavus and Pencillium chrysogenum using a green approach and to test the antifungal activity of these synthesized AgNPs against a variety of pathogenic fungi. The characterization of samples was done by using UV-visible spectroscopy, SEM (scanning electron microscopy), FTIR (Fourier transmission infrared spectroscopy), and XRD (X-ray diffractometry). The investigation confirmed the creation of AgNPs by the fungi Aspergillus niger, Aspergillus flavus and Pencillium chrysogenum, as evidenced by prominent plasmon absorbance bands at 420 and 450 nm.The biosynthesized AgNPs were 80-100 nm in size, asymmetrical in shape and became spherical to sub-spherical when aggregated. Agar well diffusion method was performed to evaluate the antifungal activity of AgNPs against various plant pathogenic fungi. An efficient and strong antifungal activity was shown by these biosynthesized nanoparticles against serious plant pathogenic fungi, viz. Aspergillus terreus, Fusarium oxysporum, Penicillium citrinum, Rhizopus stolonifer and Mucor mucedo. The biosynthesized AgNPs at various concentrations caused significant zone of inhibition in the test fungal pathogens. Silver nanoparticles (AgNPs) biosynthesized from Aspergillus niger at highest concentrations showed maximum zone of inhibition against Penicillium citrinum (19.33 ± 0.57 mm) followed by Rhizopus stolonifer (17.66 ± 0.57), Aspergillus terreus (16.33 ± 1.54 mm), Fusarium oxysporum (14.00 ± 1.00 mm) and Mucor mucedo (13.33 ± 1.15 mm) respectively. Therefore, the findings clearly indicate that silver nanoparticles could play a significant role in managing diverse plant diseases caused by fungi.
Assuntos
Antifúngicos , Aspergillus flavus , Aspergillus niger , Fusarium , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata , Prata/farmacologia , Prata/química , Prata/metabolismo , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Nanopartículas Metálicas/química , Fusarium/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Aspergillus flavus/efeitos dos fármacos , Aspergillus flavus/metabolismo , Aspergillus niger/efeitos dos fármacos , Aspergillus/efeitos dos fármacos , Aspergillus/metabolismo , Fungos/efeitos dos fármacos , Difração de Raios X , Microscopia Eletrônica de Varredura , Química Verde , Doenças das Plantas/microbiologiaRESUMO
Response surface methodology (RSM) was employed to optimize the process parameters of the supercritical carbon dioxide extraction of hop cones in terms of their antifungal properties against Fusarium culmorum and Aspergillus niger. The effects of temperature (40-50 °C), pressure (200-300 bar), and CO2 consumption (25-75 kgCO2/kg) on the extraction yield, content of α- and ß-acids, as well as pathogens' growth inhibition were investigated. Both pressure and CO2 consumption had a significant effect on antifungal properties. It was observed that the best results for antifungal properties were obtained when hop cones were extracted with pure carbon dioxide at the temperature of 50 °C, under the pressure of 300 bar with CO2 consumption at the level of 75 kgCO2/kg of feed for extraction. The highest antifungal properties of hop cone supercritical carbon dioxide extracts were analyzed as 100% for Fusarium culmorum and 68% for Aspergillus niger, calculated as the growth inhibition of tested pathogens. The aim of the study was to determine the optimum values of extraction parameters to achieve the maximum response and enable us to investigate the interaction of these parameters on the antifungal properties of hop cone extracts.
Assuntos
Antifúngicos , Aspergillus niger , Dióxido de Carbono , Fusarium , Extratos Vegetais , Dióxido de Carbono/química , Antifúngicos/farmacologia , Antifúngicos/química , Fusarium/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Humulus/química , Testes de Sensibilidade Microbiana , TemperaturaRESUMO
The potential biopreservative role of a Type III sourdough (tIII-SD), produced by starter cultures of Fructilactobacillus sanfranciscensis and Lactiplantibacillus plantarum ATCC 8014, was assessed for its antifungal activity in baking applications. Fermentation was carried out using different substrates to enhance the production of antifungal metabolites for 24 and 48 h. The tIII-SD samples were analyzed in relation to pH, total titratable acidity (TTA) and the production of organic acids. The water/salt-soluble extract of the tIII-SD was evaluated in relation to the inhibition potential against key fungi that contaminate bakery products including Penicillium roqueforti, Penicillium chrysogenum and Aspergillus niger. Finally, breads with 10 % of the tIII-SD were prepared and the fungi contamination was evaluated throughout the shelf life period. The lowest pH value in sourdough was obtained from 48-hour fermentation by L. plantarum. The saline extracts exhibited varying degrees of inhibition in the in vitro test; however, the greatest enhancement of this effect was obtained when whole wheat grain flour was used. The tIII-SD crafted from a blend of wheat and flaxseed flours and fermented with F. sanfranciscensis for 48 h (BSWF48h-FS), demonstrated superior performance compared to other formulations. This variant exhibited a total shelf life of 10 days, suggesting that the utilization of tIII-SD could serve as a viable alternative for natural antifungal agents, proving beneficial for the bakery industry.
Assuntos
Antifúngicos , Pão , Fermentação , Microbiologia de Alimentos , Pão/microbiologia , Pão/análise , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Penicillium/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Farinha/análise , Conservação de Alimentos/métodos , Triticum/química , Triticum/microbiologia , Penicillium chrysogenum , Lactobacillus plantarum/metabolismoRESUMO
This study introduces and assesses the potential of a Luliconazole-loaded nanofiber (LUL-NF) patch, fabricated through electrospinning, for enhancing topical drug delivery. The primary objectives involve evaluating the nanofiber structure, characterizing physical properties, determining drug loading and release kinetics, assessing antifungal efficacy, and establishing the long-term stability of the NF patch. LUL-NF patches were fabricated via electrospinning and observed by SEM at approximately 200 nm dimensions. The comprehensive analysis included physical properties (thickness, folding endurance, swelling ratio, weight, moisture content, and drug loading) and UV analysis for drug quantification. In vitro studies explored sustained drug release kinetics, while microbiological assays evaluated antifungal efficacy against Candida albicans and Aspergillus Niger. Stability studies confirmed long-term viability. Comparative analysis with the pure drug, placebo NF patch, LUL-NF patch, and Lulifod gel was conducted using agar diffusion, revealing enhanced performance of the LUL-NF patch. SEM analysis revealed well-defined LUL-NF patches (0.80 mm thickness) with exceptional folding endurance (> 200 folds) and a favorable swelling ratio (12.66 ± 0.73%). The patches exhibited low moisture uptake (3.4 ± 0.09%) and a moisture content of 11.78 ± 0.54%. Drug loading in 1 cm2 section was 1.904 ± 0.086 mg, showing uniform distribution and sustained release kinetics in vitro. The LUL-NF patch demonstrated potent antifungal activity. Stability studies affirmed long-term stability, and comparative analysis highlighted increased inhibition compared to a pure drug, LUL-NF patch, and a commercial gel. The electrospun LUL-NF patch enhances topical drug delivery, promising extended therapy through single-release, one-time application, and innovative drug delivery strategies, supported by thorough analysis.
Assuntos
Antifúngicos , Aspergillus niger , Candida albicans , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Imidazóis , Nanofibras , Antifúngicos/administração & dosagem , Antifúngicos/farmacologia , Antifúngicos/química , Nanofibras/química , Candida albicans/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Imidazóis/química , Imidazóis/administração & dosagem , Imidazóis/farmacologia , Preparações de Ação Retardada , Testes de Sensibilidade Microbiana/métodos , Portadores de Fármacos/química , Estabilidade de MedicamentosRESUMO
A new compound xylarkarynone A (1), a first reported natural product compound xylarkarynone B (2) and eight known compounds (3-10) were isolated from Xylaria sp. HHY-2. Their structures were elucidated by spectroscopic methods, DP4+ probability analyses and electronic circular dichroism (ECD) calculations. The bioactivities of isolated compounds were assayed. Compound 1 exhibited obvious activity against A549 cells with an IC50 value of 6.12±0.28â µM. Additionally, compound 1 showed moderate antifungal activities against Plectosphaerella cucumerina and Aspergillus niger with minimum inhibitory concentrations (MICs) of both 16â µg/mL, which was at the same grade with positive control nystatin. Most compounds exhibited varying degrees of inhibitory activity against P. cucumerina, indicating that Xylaria sp. has potential as inhibitors against P. cucumerina.
Assuntos
Antifúngicos , Aspergillus niger , Testes de Sensibilidade Microbiana , Sesquiterpenos , Xylariales , Humanos , Xylariales/química , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Aspergillus niger/efeitos dos fármacos , Células A549 , Ensaios de Seleção de Medicamentos Antitumorais , Ascomicetos/química , Estrutura Molecular , Conformação Molecular , Relação Estrutura-Atividade , Relação Dose-Resposta a DrogaRESUMO
A new series of isatin-Schiff base linked 1,2,3-triazole hybrids has been synthesized using CuAAC approach from (E)-3-(phenylimino)-1-(prop-2-yn-1-yl)indolin-2-one derivatives in high yield (73-91â %). These synthesized derivatives were characterized using FT-IR, 1H NMR, 13C NMR, 2D-NMR and HRMS spectral techniques. The in vitro antimicrobial activity assay demonstrated that most of the tested hybrids exhibited promising activity. Compoundâ 5 j displayed significant antibacterial efficacy against P. aeruginosa and B. subtilis with MIC value of 0.0062â µmol/mL. While, 5 j also showed better antifungal potency against A. niger with MIC value of 0.0123 µmol/mL. The docking studies of most promising compounds were performed with the well-known antibacterial and antifungal targets i. e. 1KZ1, 5TZ1. Molecular modelling investigations demonstrated that hybrids 5 h and 5 l exhibited good interactions with 1KZN and 5TZ1, with binding energies of -9.6 and -11.0â kcal/mol, respectively. Further, molecular dynamics studies of the compounds showing promising binding interactions were also carried out to study the stability of complexes of these hybrids with both the targets.
Assuntos
Antibacterianos , Antifúngicos , Isatina , Testes de Sensibilidade Microbiana , Bases de Schiff , Triazóis , Bases de Schiff/química , Bases de Schiff/farmacologia , Bases de Schiff/síntese química , Isatina/química , Isatina/farmacologia , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Simulação de Acoplamento Molecular , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Relação Estrutura-Atividade , Relação Dose-Resposta a DrogaRESUMO
Cinnamaldehyde displays strong antifungal activity against fungi such as Aspergillus niger, but its precise molecular mechanisms of antifungal action remain inadequately understood. In this investigation, we applied chemoproteomics and bioinformatic analysis to unveil the target proteins of cinnamaldehyde in Aspergillus niger cells. Additionally, our study encompassed the examination of cinnamaldehyde's effects on cell membranes, mitochondrial malate dehydrogenase activity, and intracellular ATP levels in Aspergillus niger cells. Our findings suggest that malate dehydrogenase could potentially serve as an inhibitory target of cinnamaldehyde in Aspergillus niger cells. By disrupting the activity of malate dehydrogenase, cinnamaldehyde interferes with the mitochondrial tricarboxylic acid (TCA) cycle, leading to a significant decrease in intracellular ATP levels. Following treatment with cinnamaldehyde at a concentration of 1 MIC, the inhibition rate of MDH activity was 74.90 %, accompanied by an 84.5 % decrease in intracellular ATP content. Furthermore, cinnamaldehyde disrupts cell membrane integrity, resulting in the release of cellular contents and subsequent cell demise. This study endeavors to unveil the molecular-level antifungal mechanism of cinnamaldehyde via a chemoproteomics approach, thereby offering valuable insights for further development and utilization of cinnamaldehyde in preventing and mitigating food spoilage.
Assuntos
Acroleína , Acroleína/análogos & derivados , Antifúngicos , Aspergillus niger , Proteínas Fúngicas , Malato Desidrogenase , Acroleína/farmacologia , Aspergillus niger/efeitos dos fármacos , Malato Desidrogenase/metabolismo , Proteínas Fúngicas/metabolismo , Antifúngicos/farmacologia , Trifosfato de Adenosina/metabolismo , Proteômica , Testes de Sensibilidade Microbiana , Ciclo do Ácido Cítrico/efeitos dos fármacosRESUMO
Hereunder, we pioneered the synthesis of Copper Oxide nanoparticles (CuO NPs) utilizing Tragacanth gum (TG). The NPs were characterized using advanced techniques and assessed for different pharmaceutical and environmental perspectives. The successful formation of a colloidal NPs solution was confirmed by the appearance of a distinct black color and a distinct peak at 260 nm in UV-Visible spectrophotometry. The FTIR analysis unveiled a spectrum of functional groups responsible for the reduction and stabilization of CuO NPs. Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) revealed size of NPs as 36.24 nm and 28 ± 04 nm respectively. Energy Dispersive X-ray (EDX) Analysis indicated weight percentages of 70.38 % for Cu and 18.88 % for O, with corresponding atomic percentages. The X-ray Diffraction (XRD) analysis revealed the orthorhombic crystal structure of the prepared CuO NPs. Antimicrobial assessments through disc-diffusion assays demonstrated significant zones of inhibition (ZOI) against gram-positive bacterial strains (Bacillus Halodurans and Micrococcus leutus) and a gram-negative bacterial strain (E. coli). Against the fungal strain Aspergillus niger, a ZOI of 18.5 ± 0.31 mm was observed. The NPs exhibited remarkable antioxidant potential determined through 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and H2O2 scavenging assays. At a concentration of 3 mg/mL, the NPs demonstrated biofilm inhibition rates of 96 %, 90 %, 89.60 %, and 72.10 % against Micrococcus luteus, Bacillus halodurans, MRSA and E.coli respectively. Furthermore, the CuO NPs showed a high photocatalytic potential towards the degradation of safranin dye under sunlight irradiation. In conclusion, the findings underline the promising multifunctional properties of TG-based CuO NPs for different practical applications.
Assuntos
Biofilmes , Cobre , Nanopartículas Metálicas , Tragacanto , Cobre/química , Tragacanto/química , Biofilmes/efeitos dos fármacos , Catálise , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Aspergillus niger/efeitos dos fármacos , Processos FotoquímicosRESUMO
The demand for environment-friendly cleanup techniques has arisen due to an increase in environmental pollutants. Fungi is the most prevalent and effective class of heavy metal-resistant microorganisms with the ability to leach metals. The objective of the present study was to isolate the fungi from the agricultural soil of Kashmir valley, investigate their multi-metal tolerance to heavy metals and evaluate the metal uptake capacities of the resistant fungi. The fungi were isolated and identified on the basis of morphological and molecular approach (ITS1 and ITS4). The tolerance limits of the isolated fungal strains to various doses of lead (Pb), cadmium (Cd), zinc (Zn), chromium (Cr), copper (Cu), nickel (Ni), and cobalt (Co) was evaluated. Five fungal strains, Aspergillus niger, Fusarium oxysporum, Fusarium verticillioides, Aspergillus fischeri, Epicoccum mackenziei were isolated from the soil samples. To the best of our knowledge, this is the first report on the study of metal resistance of Aspergillus fischeri and Epicoccum mackenziei. Among the identified fungal species, Aspergillus niger and Fusarium oxysporum were found to be most tolerant with a minimum inhibitory concentration (MIC) of 600 ppm against Cu and Cr respectively. Results indicated removal of considerable amount of heavy metals by some of the fungi. The highest metal uptake of 8.31 mg/g was found in Fusarium verticillioides for Zn. Surprisingly, these fungal strains demonstrated resistance to metal concentrations above the levels that are universally acceptable for polluted soils, and hence prove to be appealing contenders for use as bioremediation agents for cleaning up heavy metal-polluted environments.
Assuntos
Fungos , Fusarium , Metais Pesados , Testes de Sensibilidade Microbiana , Microbiologia do Solo , Poluentes do Solo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Fungos/efeitos dos fármacos , Fungos/isolamento & purificação , Fungos/classificação , Fungos/metabolismo , Fusarium/isolamento & purificação , Fusarium/efeitos dos fármacos , Fusarium/metabolismo , Biodegradação Ambiental , Aspergillus niger/isolamento & purificação , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/metabolismo , Solo/química , Aspergillus/efeitos dos fármacos , Aspergillus/metabolismo , Aspergillus/isolamento & purificaçãoRESUMO
Postharvest loss caused by a range of pathogens necessitates exploring novel antifungal compounds that are safe and efficient in managing the pathogens. This study evaluated the antifungal activity of ethyl ferulate (EF) and explored its mechanisms of action against Alternaria alternata, Aspergillus niger, Botrytis cinerea, Penicillium expansum, Penicillium digitatum, Geotrichum candidum and evaluated its potential to inhibit postharvest decay. The results demonstrated that EF exerts potent antifungal activity against a wide board of postharvest pathogens. Results also revealed that its antifungal mechanism is multifaceted: EF may be involved in binding to and disturbing the integrity of the fungal plasma membrane, causing leakage of intracellular content and losing normal morphology and ultrastructure. EF also induced oxidative stress in the pathogen, causing membrane lipid peroxidation and malondialdehyde accumulation. EF inhibited the critical gene expression of the pathogen, affecting its metabolic regulation, antioxidant metabolism, and cell wall degrading enzymes. EF exhibited antifungal inhibitory activity when applied directly into peel wounds or after incorporation with chitosan coating. Due to its wide board and efficient antifungal activity, EF has the potential to provide a promising alternative to manage postharvest decay.
Assuntos
Antifúngicos , Botrytis , Ácidos Cafeicos , Penicillium , Penicillium/efeitos dos fármacos , Penicillium/metabolismo , Antifúngicos/farmacologia , Botrytis/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Alternaria/efeitos dos fármacos , Aspergillus niger/efeitos dos fármacos , Conservação de Alimentos/métodos , Geotrichum/efeitos dos fármacos , Fungos/efeitos dos fármacos , Microbiologia de Alimentos , Frutas/microbiologia , Estresse Oxidativo/efeitos dos fármacosRESUMO
Herein, carvacrol (CRV) and modified cellulose nanocrystal-zinc oxide (CNC-ZnO) were incorporated into a poly (lactic acid) (PLA) matrix to prepare a PLA-based composite film using a simple solution casting method to achieve antimicrobial effects for application in antimicrobial food packaging. Compared with films obtained from neat PLA, the PLA@CRV20%@CNC-ZnO3% composite film shows better performance in terms of mechanical properties, ultraviolet (UV) blocking, and antimicrobial effects. The PLA composites containing CRV and 3 wt% CNC-ZnO blends exhibit improved tensile strength (21.8 MPa) and elongation at break (403.1 %) as well as excellent UV resistance. In particular, CRV and the CNC-ZnO hybrid endow the obtained PLA composite films with a synergistic antibacterial effect, resulting in good antibacterial properties for microbes, such as Escherichia coli, Staphylococcus aureus and Aspergillus niger. The diameters of the inhibition zone of the PLA@CRV20%@CNC-ZnO3% composite films against E. coli, S. aureus, and A. niger were 4.9, 5.0, and 3.4 cm, respectively. Appling the PLA@CRV20%@CNC-ZnO3% composite film as an antibacterial food packaging material, the storage period for strawberries was considerably extended. This study provides a theoretical basis for developing new organic/inorganic composite antimicrobial film materials from PLA.
Assuntos
Antibacterianos , Celulose , Cimenos , Embalagem de Alimentos , Nanopartículas , Poliésteres , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Poliésteres/química , Cimenos/química , Cimenos/farmacologia , Celulose/química , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas/química , Embalagem de Alimentos/métodos , Staphylococcus aureus/efeitos dos fármacos , Nanocompostos/química , Escherichia coli/efeitos dos fármacos , Resistência à Tração , Testes de Sensibilidade Microbiana , Aspergillus niger/efeitos dos fármacosRESUMO
This study investigates the effects of SCG embedded into biodegradable polymer blends and aimed to formulate and characterise biomass-reinforced biocomposites using spent coffee ground (SCG) as reinforcement in PHB/PLA polymer blend. The effect of SCG filler loading and varying PHB/PLA ratios on the tensile properties and morphological characteristics of the biocomposites were examined. The results indicated that tensile properties reduction could be due to its incompatibility with the PHB/PLA matrixSCG aggregation at 40â¯wt% content resulted in higher void formation compared to lower content at 10â¯wt%. A PHB/PLA ratio of 50/50 with SCG loading 20â¯wt% was chosen for biocomposites with treated SCG. Biological treatment of SCG using Phanerochaete chrysosporium CK01 and Aspergillus niger DWA8 indicated P. chrysosporium CK01 necessitated a higher moisture content for optimum growth and enzyme production, whereas the optimal conditions for enzyme production (50-55â¯%, w/w) differed from those promoting A. niger DWA8 growth (40â¯%, w/w). SEM micrographs highlighted uniform distribution and effective wetting of treated SCG, resulting in improvements of tensile strength and modulus of biocomposites, respectively. The study demonstrated the effectiveness of sustainable fungal treatment in enhancing the interfacial adhesion between treated SCG and the PHB/PLA matrix.
Assuntos
Aspergillus niger , Café , Hidroxibutiratos , Poliésteres , Poliésteres/química , Hidroxibutiratos/química , Café/química , Aspergillus niger/efeitos dos fármacos , Resistência à Tração , Polímeros/químicaRESUMO
BACKGROUND: Every year Invasive Fungal Infections (IFI) are globally affecting millions of people. Candida albicans and Aspergillus niger have been reported as the most infectious and mortality-inducing fungal strains among all pathogenic fungi. AIMS & OBJECTIVES: To tackle this problem in the current study Pyranopyrazoles and Pyrazolopyrano- pyrimidine derivatives were developed using molecular hybridization, green chemistry and one-pot multicomponent reaction. MATERIALS AND METHODS: In the present work, New Chemical entities (NCE's) were developed on the basis of Structure activity relationship. All designed NCE's were screened for ADMET studies using the QikProp module of Schrodinger software. NCE's with zero violations were further docked on the crystal structure of 14α demethylase, cytochrome P450 and thymidine synthase (PDB ID: 5V5Z, 7SHI, 1BID). Selected molecules were synthesized using green chemistry techniques and evaluated for in vitro antifungal activity against Candida albicans and Aspergillus niger. RESULTS AND DISCUSSION: Designed NCE's (B1-12 and C1-11) showed favorable results in ADMET studies. In the docking study six compounds from series-B and five molecules from series- C showed good dock score and binding interaction when compared with the standard drugs. Compounds B-3 and C-4 showed the highest zone of inhibition activity against Candida albicans, where as B-1 and C-3 had shown highest zone of inhibition activity against Aspergillus niger. CONCLUSION: Bicyclic ring (series B) showed better activity as compare to fused tricyclic ring (series C).
Assuntos
Antifúngicos , Aspergillus niger , Candida albicans , Química Verde , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Pirazóis , Pirimidinas , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/síntese química , Pirimidinas/farmacologia , Pirimidinas/química , Pirimidinas/síntese química , Aspergillus niger/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Pirazóis/farmacologia , Pirazóis/química , Pirazóis/síntese química , Relação Estrutura-Atividade , Simulação por Computador , Desenho de Fármacos , HumanosRESUMO
In vitro antimicrobial activity of nano-ZnO-loaded nanoliposomes at different levels of lecithin:nano-ZnO ratio (5:1, 15:1, and 25:1 w/w) against Aspergillus niger (IBRC-M 30095) and Botrytis cinerea (IBRC-M 30162) was evaluated. Nanoliposome formulations containing nano-ZnO were fabricated through thin-layer hydration sonication and heat methods. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of nano-ZnO-loaded nanoliposomes and free nano-ZnO against Aspergillus niger and Botrytis cinerea were determined. The time-kill experiments were performed for each isolate. Results showed that the encapsulation of nano-ZnO in nanoliposome systems significantly enhanced their antimicrobial activities by improving the penetration of ZnO nanoparticles the fungi cell membrane. In vitro antifungal activity of nano-ZnO-loaded nanoliposomes against Aspergillus niger and Botrytis cinerea was increased in thin-layer hydration sonication method compared with the heat method. The log phase for Aspergillus niger and Botrytis cinerea was around 70 h. Adding nano-ZnO-loaded nanoliposomes to the culture medium shortened the log phase for both Aspergillus niger and Botrytis cinerea. The highest antimicrobial activity of nanoliposomes was achieved using nanoliposomes containing the lecithin:nano-ZnO ratio of 25:1 (w/w) as compared to all samples. However, the length of the log phase growth cultures exposed to the nanoliposome formulations prepared by thin-layer hydration sonication method with the lecithin:nano-ZnO ratio of 25:1 (w/w) at MIC and MFC values was 60 and 40 h for both Aspergillus niger and Botrytis cinerea, respectively.