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1.
Medicina (Kaunas) ; 60(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38541241

RESUMO

Background and Objectives: Urinary tract infections [UTIs] are considered the third most known risk of infection in human health around the world. There is increasing appreciation for the pathogenicity of Gram-positive and Gram-negative strains in UTIs, aside from fungal infection, as they have numerous virulence factors. Materials and Methods: In this study, fifty urine samples were collected from patients suffering from UTI. Among the isolates of UTI microbes, six isolates were described as MDR isolates after an antibiotic susceptibility test carried out using ten different antibiotics. An alternative treatment for microbial elimination involved the use of biosynthesized silver nanoparticles (AgNPs) derived from Solanum lycopersicum [S. cumin]. Results: The sizes and shapes of AgNPs were characterized through TEM imaging, which showed spherical particles in a size range of 35-80 nm, of which the average size was 53 nm. Additionally, the silver nanoparticles (AgNPs) demonstrated inhibitory activity against Staphylococcus aureus (OR648079), exhibiting a 31 mm zone of inhibition at a minimum inhibitory concentration (MIC) of 4 mg/mL and a minimum bactericidal concentration (MBC) of 8 mg/mL. This was followed by Aspergillus niger (OR648075), which showed a 30 mm inhibition zone at an MIC of 16 mg/mL and a minimum fungicidal concentration (MFC) of 32 mg/mL. Then, Enterococcus faecalis (OR648078), Klebsiella pneumoniae (OR648081), and Acinetobacter baumannii (OR648080) each displayed a 29 mm zone of inhibition at an MIC of 8 mg/mL and an MBC of 16 mg/mL. The least inhibition was observed against Candida auris (OR648076), with a 25 mm inhibition zone at an MIC of 16 mg/mL and an MFC of 32 mg/mL. Furthermore, AgNPs at different concentrations removed DPPH and H2O2 at an IC50 value of 13.54 µg/mL. Also, AgNPs at 3 mg/mL showed remarkable DNA fragmentation in all bacterial strains except Enterococcus faecalis. The phytochemical analysis showed the presence of different active organic components in the plant extract, which concluded that rutin was 88.3 mg/g, garlic acid was 70.4 mg/g, and tannic acid was 23.7 mg/g. Finally, AgNPs concentrations in the range of 3-6 mg/mL showed decreased expression of two of the fundamental genes necessary for biofilm formation within Staphylococcus aureus, fnbA (6 folds), and Cna (12.5 folds) when compared with the RecA gene, which decreased by one-fold when compared with the control sample. These two genes were submitted with NCBI accession numbers [OR682119] and [OR682118], respectively. Conclusions: The findings from this study indicate that biosynthesized AgNPs from Solanum lycopersicum exhibit promising antimicrobial and antioxidant properties against UTI pathogens, including strains resistant to multiple antibiotics. This suggests their potential as an effective alternative treatment for UTIs. Further research is warranted to fully understand the mechanisms of action and to explore the therapeutic applications of these nanoparticles in combating UTIs.


Assuntos
Adesinas Bacterianas , Anti-Infecciosos , Nanopartículas Metálicas , Polifenóis , Solanum lycopersicum , Humanos , Prata/farmacologia , Antioxidantes/farmacologia , Virulência , Nanopartículas Metálicas/uso terapêutico , Peróxido de Hidrogênio/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Staphylococcus aureus , Biofilmes , Anti-Inflamatórios/farmacologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-32834922

RESUMO

ABSTRACT: The current outbreak of the highly transmittable and life-threatening severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved rapidly and posed a global health emergency. Many clinical trials are now being conducted to test possible therapies. To assist this, virtual screening via molecular docking was performed on several FDA-approved drugs, previously used in epidemics, and the top ten compounds were selected. These ten well-characterized drugs, previously used to treat malaria and Ebola infections, were screened based on their interactions with the SARS-CoV-2 ACE2 receptor and 3C-like protease. Compared to the other nine medicines, brincidofovir, an ether lipid ester analog of cidofovir with potent antiviral activity, showed the highest docking scores and binding interactions. Therefore, brincidofovir is worth further investigations and clinical trials as a possible therapeutic agent for the COVID-19 disease caused by the novel SARS-CoV-2.

3.
Bioresour Technol ; 184: 123-130, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25466992

RESUMO

Microalgae are a promising alternative for sustainable biofuel production, but production yields and costs present a significant bottleneck. Here, the use of glycerol and xylose to boost the lipid yield was evaluated using ten strains from the Université de Montréal collection of microalgae. This report shows that some microalgal strains are capable of mixotrophic and heterotrophic growth on xylose, the major carbon source found in wastewater streams from pulp and paper industries, with an increase in growth rate of 2.8-fold in comparison to photoautotrophic growth, reaching up to µ=1.1/d. On glycerol, growth rates reached as high as µ=1.52/d. Lipid productivity increased up to 370% on glycerol and 180% on xylose for the strain LB1H10, showing the suitability of this strain for further development of biofuels production through mixotrophic cultivation.


Assuntos
Biocombustíveis/microbiologia , Glicerol/farmacologia , Lipídeos/biossíntese , Microalgas/crescimento & desenvolvimento , Xilose/farmacologia , Processos Autotróficos/efeitos dos fármacos , Biomassa , Ésteres/metabolismo , Ácidos Graxos/metabolismo , Microalgas/efeitos dos fármacos , Processos Fototróficos/efeitos dos fármacos
4.
Bioresour Technol ; 157: 140-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24549235

RESUMO

Biodiesel production from microalgae lipids is being considered as a potential source of renewable energy. However, practical production processes will probably require the use of local strains adapted to prevailing climatic conditions. This report describes the isolation of 100 microalgal strains from freshwater lakes and rivers located in the vicinity of Montreal, Quebec, Canada. Strains were identified and surveyed for their growth on secondary effluent from a municipal wastewater treatment plant (La Prairie, QC, Canada) using a simple and high throughput microalgal screening method employing 12 well plates. The biomass and lipid productivity of these strains on wastewater were compared to a synthetic medium under different temperatures (10±2°C and 22±2°C) and a number identified that showed good growth at 10°C, gave a high lipid content (ranging from 20% to 45% of dry weight) or a high capacity for nutrient removal.


Assuntos
Biocombustíveis/microbiologia , Microalgas/metabolismo , Águas Residuárias/microbiologia , Purificação da Água/métodos , Biomassa , Fluorescência , Lipídeos/análise , Microalgas/crescimento & desenvolvimento , Nitratos/análise , Fosfatos/análise , Quebeque
5.
Environ Technol ; 34(13-16): 1783-805, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24350435

RESUMO

Microalgae hold promise for the production of sustainable replacement of fossil fuels due to their high growth rates, ability to grow on non-arable land and their high content, under the proper conditions, of high energy compounds that can be relatively easily chemically converted to fuels using existing technology. However, projected large-scale algal production raises a number of sustainability concerns concerning land use, net energy return, water use and nutrient supply. The state-of-the-art of algal production of biofuels is presented with emphasis on some possible avenues to provide answers to the sustainability questions that have been raised. Here, issues concerning algal strains and supply of nutrients for large-scale production are discussed. Since sustainability concerns necessitate the use of wastewaters for supply of bulk nutrients, emphasis is placed on the composition and suitability of different wastewater streams. At the same time, algal cultivation has proven useful in waste treatment processes, and thus this aspect is also treated in some detail.


Assuntos
Biocombustíveis , Microalgas/química , Microalgas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Conservação dos Recursos Naturais/métodos
6.
Environ Technol ; 34(13-16): 1807-36, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24350436

RESUMO

In order to ensure the sustainability of algal biofuel production, a number of issues need to be addressed. Previously, we reviewed some of the questions in this area involving algal species and the important challenges of nutrient supply and how these might be met. Here, we take up issues involving harvesting and the conversion ofbiomass to biofuels. Advances in both these areas are required if these third-generation fuels are to have a sufficiently high net energy ratio and a sustainable footprint. A variety of harvesting technologies are under investigation and recent studies in this area are presented and discussed. A number of different energy uses are available for algal biomass, each with their own advantages as well as challenges in terms of efficiencies and yields. Recent advances in these areas are presented and some of the especially promising conversion processes are highlighted.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Microalgas/química , Microalgas/metabolismo , Biomassa , Técnicas de Química Analítica/métodos , Águas Residuárias/química
7.
Bioresour Technol ; 145: 134-41, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23499181

RESUMO

Biodiesel production using microalgae is attractive in a number of respects. Here a number of pros and cons to using microalgae for biofuels production are reviewed. Algal cultivation can be carried out using non-arable land and non-potable water with simple nutrient supply. In addition, algal biomass productivities are much higher than those of vascular plants and the extractable content of lipids that can be usefully converted to biodiesel, triacylglycerols (TAGs) can be much higher than that of the oil seeds now used for first generation biodiesel. On the other hand, practical, cost-effective production of biofuels from microalgae requires that a number of obstacles be overcome. These include the development of low-cost, effective growth systems, efficient and energy saving harvesting techniques, and methods for oil extraction and conversion that are environmentally benign and cost-effective. Promising recent advances in these areas are highlighted.


Assuntos
Biofilmes , Biocombustíveis/economia , Biocombustíveis/microbiologia , Biotecnologia/tendências , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Triglicerídeos/análise , Biomassa , Biotecnologia/métodos , Dióxido de Carbono/metabolismo
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