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Arc and pulsed spark discharge inactivation of pathogenic P. aeruginosa, S. aureus, M. canis, T. mentagrophytes, and C. albicans microorganisms
2022
Rasouli, Milad | Amini, Maryam | Khandan, Saeed | Ghoranneviss, Mahmood | Nikmaram, Hamed | Ostrikov, Kostya Ken
There is a strong and ever-escalating need for sterilization tools that are effective against a broad range of pathogenic microorganisms. To address this issue, this study evaluates the inactivation potential of arc and pulsed spark plasma discharges on Pseudomonas aeruginosa, Staphylococcus aureus, Microsporum canis, Trichophyton mentagrophytes, and Candida albicans microorganisms. Our results show that the electrical discharge plasma systems are effective in the inactivation of pathogenic microorganisms. The inactivation of the considered strains was greatly affected by the type of microorganisms. Higher viability losses of the pathogenic strains were observed in bacterial strains than in the fungal strains. Moreover, in the case of fungal strains, the population of C. albicans was decreased the most, followed by Trichophyton mentagrophyte, while the population of Microsporum canis was decreased the least. Besides, the arc discharge system was compared with the pulsed spark discharge system. It can be obtained from the results that the pulsed spark discharge treatment successfully enhanced the reduction of the pathogenic cells more than the arc discharge treatment. The higher efficiency of the pulsed spark discharge is due to the generation of discharge streamers on the water surface. The SEM analyses showed that electrical discharge plasmas produced serious damage to pathogenic eukaryotic and prokaryotic microorganisms. Also, the plasma-induced changes in pH values and temperature values were measured. The pulsed spark discharge-treated samples have more significant changes in pH value while arc discharge-treated samples have larger temperature changes.
显示更多 [+] 显示较少 [-]In vitro antioxidant, antibacterial, and antihyperlipidemic potential of ethanolic Avicennia marina leaves extract supported by metabolic profiling
2021
Yassien, Eman E. | Hamed, Moaz M. | Abdelmohsen, Usama Ramadan | Hassan, Hanaa M. | Gazwi, Hanaa S. S.
This study aimed to examine the impact of ethanolic Avicennia marina (A. marina) leaves extract against seven pathogenic bacteria and the protective effect of this plant against hyperlipidemia caused by dexamethasone (DEX)-treated rats. Forty-eight male rats weighing between 150 and 200 g were randomly selected into six groups containing eight rats in each group. Moreover, in vitro antioxidant DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radical scavenging activity, FRAP (ferric reducing antioxidant power), and ABTS assay were also analyzed for leaf extract. Results showed that the IC₅₀ values were observed as 193.9 ± 1.03 μg/mL, 340.29 ± 8.16 μM TE/mg, and 326.8 ± 6.14 μM TE/mg for DPPH, FRAP, and ABTS radical scavenging activities, respectively. A. marina leaves ethanolic extract exhibited higher activity against Candida albicans and Bacillus subtilis, moderate activity against Salmonella typhimurium, and Vibrio damsel. The administration of DEX resulted in significant (P < 0.05) increase in the levels of MDA concentration, TG, TC, LDL, LDH, and glucose but decreased significantly in HDL. Treatment with A. marina extract positively reversed the distorted lipid profile and peroxidation and improved MDA, GSH, NO, and SOD activities in DEX-administered rats. Histological investigation of liver tissue sections showed that the treatment with A. marina leaves extract moderate the fatty change caused by DEX. It is concluded that A. marina leaves extract improved the hypolipidemic property of DEX administration in comparison with standard treatment with atorvastatin.
显示更多 [+] 显示较少 [-]In Situ Evaluation of Filter Media Modified by Biocidal Nanomaterials to Control Bioaerosols in Internal Environments
2021
de Freitas Rosa Remiro, Paula | de Sousa, Cristina Paiva | Alves, Henrique Cezar | Bernardo, André | Aguiar, Mônica Lopes
Controlling the bioaerosol present in indoor environments has been evidenced to be extremely necessary. An alternative is to develop filter media for air conditioners that have biocidal properties. This study aimed to verify the biocidal effect of a high-efficiency particulate air (HEPA) filter medium modified with the deposition of nanoparticles on its surface. For this purpose, Ag, TiO₂, and Ag/TiO₂ nanoparticles were used and the antimicrobial activities of these nanomaterials against Escherichia coli, Staphylococcus aureus, and Candida albicans microorganisms were evaluated, as well as the biocidal efficacy of the modified HEPA filter with these nanomaterials in a real environment. The percentages of elimination obtained for the Ag, TiO₂, and Ag/TiO₂ nanomaterials, respectively, were 53%, 63%, and 68% (E. coli); 67%, 67%, and 69% (S. aureus); and 68%, 73%, and 75% (C. albicans). The HEPA filter media had their surfaces modified by aspersion and deposition of Ag, TiO₂, and Ag/TiO₂ nanomaterials. We could conclude that the nanoparticles adhered to the filter medium do not affect its permeability. The modified filters were arranged in an internal environment (bathroom) for the collection of the bioaerosols, and after the collection, the filter cake was plated and arranged to grow in a liquid medium. The results showed that the filters have 100% of biocidal action in passing air, and 55.6%, 72.2%, and 81% of inhibition to microbial growth in their surface for modification with Ag, TiO₂, and Ag/TiO₂, respectively, compared to unmodified filters.
显示更多 [+] 显示较少 [-]Radiation-induced synthesis of copper sulfide nanotubes with improved catalytic and antibacterial activities
2021
Bekhit, Mohamad | Abo El Naga, Ahmed O. | El Saied, Mohamed | Abdel Maksoud, Mohamed I. A.
In the current paper, copper sulfide nanotubes have been successfully synthesized via the green, simple, and effective gamma-radiolysis method without adding any capping or reducing agents. The structural and morphological characteristics of the as-prepared CuS nanotubes were investigated by X-ray diffraction (XRD), N₂ adsorption-desorption measurements at 77 K, transmission electron microscopy (TEM), and ultraviolet-visible (UV-vis) spectroscopy, which all demonstrated the formation of pure CuS covellite phase with tubular morphology. The synthesized CuS nanotubes possessed not only high activity towards the reduction of both cationic (methylene blue) and anionic (Congo red) dyes in the presence of NaBH₄ but also exhibited excellent reusability. In addition, the pseudo-first-order kinetic model represented the reduction of MB very well, and the value of the normalized rate constant (2.4 × 10⁻² s⁻¹ mg⁻¹) was higher than those of other solid catalysts reported in the literature. Ultimately, CuS nanotubes were found to have a broad-spectrum microbicidal action against the common microbiota, such as Gram-positive (exemplified by Bacillus subtilis and Staphylococcus aureus), Gram-negative bacteria (exemplified by Pseudomonas aeruginosa and Escherichia coli), yeast (exemplified by Candida albicans), and plant pathogenic fungi (exemplified by Aspergillus niger).
显示更多 [+] 显示较少 [-]Chemical diversity and biological activities of essential oils from native populations of Clinopodium menthifolium subsp. ascendens (Jord.) Govaerts
2021
Debbabi, Haïfa | El Mokni, Ridha | Nardoni, Simona | Chaieb, Ikbal | Maggi, Filippo | Nzekoue, Franks Kamgang | Caprioli, Giovanni | Hammami, Saoussen
This study is focused on the analysis of regional variation of the chemical compositions of three Clinopodium menthifolium subsp. ascendens (Jord.) Govaerts Tunisian accession, as well as their inhibition toward fungi and insect pests. The diversity of the chemical constituents and biological activities in front of the aforementioned variations was found to be remarkable. Essential oils were obtained by hydrodistillation of the aerial parts and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 41, 42, and 30 compounds were identified respectively from Clinopodium menthifolium essential oils harvested from three Tunisian regions, namely Ain-Draham (ADEO), Babouch (BEO), and Tabarka (TEO). All analyzed oils were rich in oxygenated monoterpenes with different major constituents. Piperitenone (34.5%), cis-piperitone oxide (26.1%), and pulegone (47.9%) were the dominant compounds in the three volatile oils, respectively. The antifungal activity was investigated in vitro using six targeted fungal strains (Aspergillus flavus, Aspergillus terreus, Candida albicans, Microsporum canis, Microsporum gypseum, and Trichophyton mentagrophytes). The toxicity and repellency of essential oils were evaluated against the stored product pest Tribolium confusum. The tested samples were differently effective toward the target fungi and the pest depending on the variability of their chemical compositions. BEO exhibited the highest fungitoxic properties toward A. terreus mold, M. canis dermatophyte, and C. albicans yeast (the MIC values ranged from 40 to 400 μg mL⁻¹). In addition, the data showed that TEO repelled T. confusum moderately (PR = 42.5% at 2 h after exposure). Concerning the contact treatment, both ADEO and BEO were proved to possess slightly toxic effects toward T. confusum pest (% of mortality 27.5–32.5% at 5% concentration). The results showed that the geographic origin greatly influenced the chemical composition and the associated bioactivities of Clinopodium menthifolium subsp. ascendens.
显示更多 [+] 显示较少 [-]Reduced ecotoxicity and improved biodegradability of cationic biocides based on ester-functionalized pyridinium ionic liquids
2019
Trush, Maria | Metelytsia, Larysa | Semenyuta, Ivan | Kalashnikova, Larysa | Papeykin, Oleksiy | Venger, Irina | Tarasyuk, Oksana | Bodachivska, Larysa | Blagodatnyi, Volodymyr | Rogalsky, Sergiy
Ester-functionalized pyridinium ionic liquids (ILs), 1-decyloxycarbonylmethylpyridinium chloride (PyrСOOC₁₀-Cl), and 1-dodecyloxycarbonylmethylpyridinium chloride (PyrСOOC₁₂-Cl) have been synthesized and studied for their environmental toxicity. Simple long-chain pyridinium ILs, 1-dodecylpyridinium chloride (PyrC₁₂-Cl), and commercial disinfectant cetylpyridinium chloride (CPC) were used as reference compounds. Both ester-functionalized ILs and CPC showed significantly reduced antibacterial activity compared to PyrC₁₂-Cl. However, ester-functionalized ILs were found to have excellent antifungal activity towards Candida albicans fungus strains, similar to PyrC₁₂-Cl and much higher than for CPC. The molecular docking of ILs in the active site of the known antifungal target N-myristoyltransferase (Nmt) C. albicans has been conducted. The obtained results indicate the possibility of ILs binding into the Nmt pocket. The high stability of the complexes, especially for PyrCOOC₁₀-Cl, is ensured by hydrogen bonding, electrostatic anion-pi interactions, as well as hydrophobic pi-alkyl and alkyl interactions that was confirmed by calculated binding energy values. The acute toxicity studies of ester-functionalized ILs on D. rerio (zebrafish) hydrobiont have shown their dramatically reduced ecotoxicity compared to PyrC₁₂-Cl and CPC. Thus, LD₅₀ values of 15.2 mg/L and 16.8 mg/L were obtained for PyrCOOC₁₀-Cl and PyrCOOC₁₂-Cl, respectively, whereas CPC had LD₅₀ value of 0.018 mg/L. The primary biodegradation test CEC L-33-A93 of ILs indicated an improved biodegradability of ester-functionalized compounds compared to simple long-chain ILs. Based on the obtained results, PyrCOOC₁₀-Cl may be considered as very promising cationic biocide due to the combination of soft antimicrobial activity and reduced ecotoxicity, as well as improved biodegradability.
显示更多 [+] 显示较少 [-]Bioremediation of a Benzo[a]Pyrene-Contaminated Soil Using a Microbial Consortium with Pseudomonas aeruginosa, Candida albicans, Aspergillus flavus, and Fusarium sp
2015
Waszak, Dafne Q. | da Cunha, Ana Cristina B. | Agarrallua, Marcio R. A. | Goebel, Cristine S. | Sampaio, Carlos H.
Many studies have been conducted regarding the degradation of PAHs. One of the technologies that has been widely used is bioremediation due to its relatively low cost and greater efficiency for those compounds with structural complexity. Biotechnology has been used in several countries for many years and consists in the use of microorganisms (bacteria and fungi) to transform contaminants into inert substances, which is a result of the microbial activity from biochemical processes. This study aimed to develop a bioremediation methodology for the pollutant benzo[a]pyrene (B[a]P), which belongs to the group of PAHs. The potential use of a microbial consortium with Pseudomonas aeruginosa, Candida albicans, Aspergillus flavus, and Fusarium sp. for bioremediation was assessed. To confirm the pollutant reduction, quantifications of the samples were performed via gas chromatography–mass spectrometry (GC-MS). The contamination was prepared with a soil previously contaminated with B[a]P at the concentration of 3.74 mg kg⁻¹. The microbial consortium was added (16 μL g⁻¹), and samples were incubated for 42 days in an oven at 35 °C. The microbial growth curves showed representative differences between the samples in the presence and absence of the pollutant, demonstrating the possibility of bioremediation process. The final quantification of soil showed a mean concentration of 1.29 mg kg⁻¹, showed that 65.51 ± 0.95 % of the pollutant was degraded, which is an important and representative performance.
显示更多 [+] 显示较少 [-]Green sol–gel synthesis of novel nanoporous copper aluminosilicate for the eradication of pathogenic microbes in drinking water and wastewater treatment
2019
Hemdan, Bahaa Ahmed | El Nahrawy, Amany Mohamed | Mansour, Abdel-Fatah M. | Hammad, Ali Belal Abou
We used a green sol–gel synthesis method to fabricate a novel nanoporous copper aluminosilicate (CAS) material. Nanoporous CAS was characterized using X-ray powder diffraction (XRD), field emission transmission and scanning electron microscopies (FE-TEM/FE-SEM), Fourier transform infrared (FTIR) spectroscopy, and optical analyses. The CAS was also evaluated for use as a promising disinfectant for the inactivation of waterborne pathogens. The antimicrobial action and minimum inhibitory concentration (MIC) of this CAS disinfectant were determined against eight microorganisms (Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, Candida albicans, and Aspergillus niger). An antimicrobial susceptibility testing of CAS was measured. Results of disc diffusion method pointed out that the diameters of the zone using well diffusion were wider than disc diffusion methods, and the findings also showed that the MIC of the CAS disinfectant against E. coli, S. enterica, and P. aeruginosa was 100 mg/L within 20 min of contact time. Meanwhile, the MIC of the CAS disinfectant was 100 mg/L within 40 min of contact time for the other strains. The efficacy of antimicrobial action (100%) reached within 20 to 40 min against all tested microbes. Herein, the antimicrobial susceptibility testing of CAS disinfectant showed no toxicity for human and bacterial cells. It can be concluded that nanoporous CAS is a promising, economically, and worthy weapon for water disinfection.
显示更多 [+] 显示较少 [-]New applied pharmacological approach/trend on utilization of agro-industrial wastes
2018
Ragab, Tamer I. M. | Shalaby, Al Shimaa Gamal | El Awdan, Sally A. | Refaat, Ahmed | Helmy, Wafaa A.
This study aimed to transform the locally available lignocellulosic residual palm frond (PF) and rice straw (RS) wastes into multifunction added products like methylated cellulose and sulfated and phosphorylated hemicelluloses by simple processes. Hydrolysis with 2 N sulfuric acid was the most suitable reaction for microcrystalline cellulose production. The characteristics of the prepared products were studied to obtain the optimum reaction conditions. Palm frond hemicellulose (PFHC) recorded the highest antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans (22, 22, 26 mm), respectively, and phosphorylated palm frond hemicellulose (PPFHC) exhibited the highest potential antioxidant activity of approximately 60%, suggesting a possible correlation between the two bioactivities. Most of extracted celluloses and their derivatives had a variety of promising probiotic activities which are expected to reduce the side effects of the gastric mucosa and possibly play a role in curing the gastric ulcer. Accordingly, the determination of anti-inflammatory and gastroprotective activity results revealed that methylcellulose, sulfated and phosphorylated hemicelluloses showed anti-inflammatory and gastroprotective activities and the capability of all tested compounds to ameliorate the ethanol-induced gastric ulcer in rats’ stomach. All results recommended PF and RS and their derivatives to be used as a medicinal food.
显示更多 [+] 显示较少 [-]Antimicrobial, cytotoxic and antioxidative evaluation of natural deep eutectic solvents
2018
Radošević, Kristina | Čanak, Iva | Panić, Manuela | Markov, Ksenija | Bubalo, MarinaCvjetko | Frece, Jadranka | Srček, VišnjaGaurina | Redovniković, IvanaRadojčić
Natural deep eutectic solvents (NADES) are a new generation of green solvents. They are mixtures of two or three compounds such as choline chloride as a cationic salt and alcohols, acids, amides, amines or sugars as hydrogen-bond donors. Although the majority of NADES’ components are of natural origin and therefore NADES are often presumed to be non-toxic, the evaluation of their toxicity and biodegradability must accompany the research on their synthesis and application. Therefore, the aim of this work was to investigate the effect of ten synthesised NADES towards bacteria (i.e., Escherichia coli, Proteus mirabilis, Salmonella typhimurium, Pseudomonas aeruginosa, Staphylococcus aureus), yeast (i.e., Candida albicans) and human cell lines (i.e., HeLa, MCF-7 and HEK293T). In addition, oxygen radical absorbance capacity (ORAC) method was used to determine the antioxidative activity of the tested NADES. Differences in toxicity response between microorganisms and cell lines were observed, and only NADES that contained organic acid showed toxicity towards the test systems. Furthermore, the NADES containing compounds that possess antioxidative activity also showed antioxidative activity. However, research whose primary purpose is the synthesis and application of NADES must be followed by an evaluation of their biological properties (e.g., antimicrobial activity, toxicity towards animal cells and antioxidative or other biological activity) to find the solvent with the best profile for wider industrial applications.
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