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1.
Polymers (Basel) ; 15(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37765518

RESUMO

Wood plastic composite (WPC) usage and demand have increased because of its interesting chemical and mechanical properties compared to other plastic materials. However, there is a possibility of structural and mechanical changes to the material when exposed to the external environment; most research on wood plastic is performed on the material with elevated fiber content (40-70%). Therefore, more research needs to be performed regarding these issues, especially when the fiber content of the WPC is low. In this study, composite materials composed of high-density polyethylene (HDPE) reinforced with yellow birch fibers (20 and 30%) were made by injection molding. The fibers were treated with dissolved zinc oxide (ZnO) powder in sodium oxide (NaOH) solution, and the fabricated material was exposed to fungal rot. ZnO treatment in this case is different from most studies because ZnO nanoparticles are usually employed. The main reason was to obtain better fixation of ZnO on the fibers. The mechanical properties of the composites were assessed by the tensile and Izod impact tests. The impact energies of the samples fabricated with ZnO-treated fibers and exposed to Gloephyllum trabeum and Trametes versicolor decreased, when compared to samples fabricated with ZnO-nontreated fibers. The mechanical properties of the samples composed of ZnO-treated fibers and exposed to rot decreased, which were reported by a decreased Young's modulus and impact energies. The usage of ZnO treatment prevented mycelium proliferation, which was nonexistent on the samples. It has been noted that the decrease in mechanical properties of the treated samples was because of the action of NaOH used to dissolve the ZnO powder.

2.
Front Plant Sci ; 14: 1087035, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36938004

RESUMO

Traditional treatment of wastewaters is a burden for local governments. Using short rotation coppice willow (SRCW) as vegetal filter has several environmental and economic benefits. Here, we investigated the effect of primary wastewater irrigation on wood structure and composition of the willow cultivar Salix miyabeana 'SX67' following two years of growth. Compared to unirrigated plants (UI), stem sections of plants irrigated with primary wastewater (WWD) showed an unexpected decrease of hydraulic conductance (KS) associated with a decrease in vessel density but not vessel diameter. The majority (86%) of vessels had diameters range groups [20-30[, [30-40[and [40-50[µm and contributed to > 75% of theoretical KS, while the group class [50-60[µm (less than 10% of vessels) still accounted for > 20% of total KS regardless irrigation treatments. WWD significantly alters the chemical composition of wood with an increase of glucan content by 9 to 16.4% and a decrease of extractives by 35.3 to 36.4% when compared to UI or to plants irrigated with potable water (PW). The fertigation did also increase the proportion of the tension wood which highly correlated with glucan content. In the context of energetic transition and mitigation of climate change, such results are of high interest since WWD effectively permit the phytofiltration of large amounts of organic contaminated effluents without impairing SRCW physiology.

3.
Viruses ; 14(11)2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36366576

RESUMO

In this study, a novel antimicrobial formula that incorporates Listeria bacteriophage P100 and silver nanoparticles into an alginate matrix was successfully developed. Paper coated with the antimicrobial formula inhibited the growth of Listeria monocytogenes. The effects of alginate concentration on the formation of silver nanoparticles, silver concentration on the infectivity of phages, and of low alginate concentrations on the sustained release of silver and phages were explored. The highest antimicrobial activity of the alginate-silver coating was achieved with an alginate concentration of 1%. Adding phage P100 (109 PFU/mL) into the alginate-silver coating led to a synergic effect that resulted in a 5-log reduction in L. monocytogenes. A bioactive paper was then developed by coating a base paper with the antimicrobial formula at different coating weights, followed by infrared drying. The higher coating weight was a crucial factor for the maintenance of phage infectivity throughout the coating and drying processes. Phages incorporated into the alginate matrix remained functional even after high-temperature infrared drying. Taken together, an optimized coating matrix is critical in improving the antimicrobial performance of bioactive paper as well as maintaining phage infectivity during the paper manufacturing process.


Assuntos
Anti-Infecciosos , Bacteriófagos , Nanopartículas Metálicas , Prata/farmacologia , Contagem de Colônia Microbiana , Antibacterianos/farmacologia , Alginatos
4.
ACS Appl Bio Mater ; 5(7): 3405-3417, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35776851

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants have rapidly spread worldwide, causing coronavirus disease (COVID-19) with numerous infected cases and millions of deaths. Therefore, developing approaches to fight against COVID-19 is currently the most priority goal of the scientific community. As a sustainable solution to stop the spread of the virus, a green dip-coating method is utilized in the current work to prepare antiviral Ag-based coatings to treat cotton and synthetic fabrics, which are the base materials used in personal protective equipment such as gloves and gowns. Characterization results indicate the successful deposition of silver (Ag) and stabilizers on the cotton and polypropylene fiber surface, forming Ag coatings. The deposition of Ag and stabilizers on cotton and etched polypropylene (EPP) fabrics is dissimilar due to fiber surface behavior. The obtained results of biological tests reveal the excellent antibacterial property of treated fabrics with large zones of bacterial inhibition. Importantly, these treated fabrics exhibit an exceptional antiviral activity toward human coronavirus OC43 (hCoV-OC43), whose infection could be eliminated up to 99.8% when it was brought in contact with these fabrics after only a few tens of minutes. Moreover, the biological activity of treated fabrics is well maintained after a long period of up to 40 days of post-treatment.


Assuntos
Antivirais , COVID-19 , Humanos , Equipamento de Proteção Individual , Polipropilenos , SARS-CoV-2 , Têxteis
5.
J Environ Manage ; 316: 115165, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35544981

RESUMO

This study deals with subject sustainability assessment for industrial parks which are seen as systems of interrelated companies and infrastructures. Although sustainability was introduced into mainstream policy discourse several decades ago, it remains complex to assess, and thus to improve in an integrated way. This is particularly true for such elaborate structures as industrial parks. However, the literature has made little effort to present tools for industrial parks managers to take decisions towards sustainability. The paper develops a sustainability assessment framework aimed at industrial parks' managers. The model is based on a multi-criteria compromise aggregation principle and relies on a preliminary systemic deployment of industrial park sustainability. The presented assessment uses a double aggregation mechanism using the weighted arithmetic mean (WAM) and the Choquet integral (CI) to account for the interrelations between stakeholders involved in an industrial park. This double aggregation results in two level of assessment, offering a more comprehensive view of the examined industrial park. A first level of assessment allows managers to control and improve the performance of their industrial parks in each pillar of sustainability. The second level is the assessment of the overall sustainability, which supports the managers' analysis of their strategy to achieve sustainability. As an illustration, the model is used to assess the sustainability of a Canadian industrial park. Application of the model shows that the completion of the studied industrial park's action plan results in reaching a 54% sustainability performance considering the managers' long-term sustainability strategy and that their vision of sustainability moderately favors the simultaneous satisfaction of economic criteria with environmental or social criteria. These results illustrates the capacity of the model to guide managers in the sustainable development of their industrial parks.


Assuntos
Conservação dos Recursos Naturais , Indústrias , Canadá , Parques Recreativos , Políticas
6.
Biomed Res Int ; 2020: 1304016, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31998775

RESUMO

AIM: To evaluate in vitro the antibacterial effect of a paper made of silver phosphate cellulose fibers (SPCF) on Staphylococcus aureus, the most common diabetic foot ulceration (DFU) pathogen when compared with other common commercial products. METHODS: The antibacterial activity of SPCF samples was evaluated through time with cell counting on agar plates. SPCF samples were then compared with commercial wound care products currently in use in DFU treatments (Silvercel™, Acticoat 7, and Aquacel Ag ExtraTM) through time on agar plates (growth inhibition zones). RESULTS: After 6 hours, there was no viable bacterial cell detected on either plate (p < 0.05). There was a net growth inhibition zone for SPCF samples but no significant difference between the two silver concentrations. Compared with common commercial products, SPCF paper provides results equal to Acticoat 7 (p < 0.05). There was a net growth inhibition zone for SPCF samples but no significant difference between the two silver concentrations. Compared with common commercial products, SPCF paper provides results equal to Acticoat 7 (p < 0.05). There was a net growth inhibition zone for SPCF samples but no significant difference between the two silver concentrations. Compared with common commercial products, SPCF paper provides results equal to Acticoat 7 (. CONCLUSIONS: These results have shown the efficiency of SPCF paper to eliminate Staphylococcus aureus in these conditions. SPCF papers are effective when compared with other common commercial products and could have an industrial potential in wound care. Infected DFU could benefit from the antibacterial effectiveness of SPCF, but more relevant experimentations related to foot ulcers are needed.Staphylococcus aureus, the most common diabetic foot ulceration (DFU) pathogen when compared with other common commercial products.


Assuntos
Antibacterianos , Bandagens , Celulose , Pé Diabético , Papel , Fosfatos , Compostos de Prata , Infecções Cutâneas Estafilocócicas/terapia , Staphylococcus aureus/crescimento & desenvolvimento , Antibacterianos/química , Antibacterianos/farmacologia , Celulose/química , Celulose/farmacologia , Pé Diabético/microbiologia , Pé Diabético/patologia , Pé Diabético/terapia , Humanos , Fosfatos/química , Fosfatos/farmacologia , Compostos de Prata/química , Compostos de Prata/farmacologia
7.
Bioresour Technol ; 282: 398-406, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30884460

RESUMO

Lignocellulosic biomass is a sustainable source of renewable substrate to produce low carbon footprint energy and materials. Biomass conversion is usually performed in two steps: a biomass pretreatment for improving cellulose accessibility followed by enzymatic hydrolysis of cellulose. In this study we investigated the efficiency of a bioextrusion pretreatment (extrusion in the presence of cellulase enzyme) for production of reducing sugars from corn crop agricultural residues. Our results demonstrate that bioextrusion increased the reducing sugar conversion yield by at least 94% at high solid/liquid ratio (14%-40%). Monitoring biomass surface with carbohydrate-binding modules (FTCM-depletion assay) revealed that well known negative impact of high solid/liquid ratio on conversion yield is not due to the lack of exposed cellulose which was abundant under such conditions. Bioextrusion was found to be less efficient on alkaline pretreated biomass but being a mild and solvent limiting pretreatment, it might help to minimize the waste stream.


Assuntos
Biomassa , Zea mays/metabolismo , Metabolismo dos Carboidratos , Carboidratos , Celulase/metabolismo , Celulose/metabolismo , Hidrólise
8.
Bioresour Technol ; 267: 657-665, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30059946

RESUMO

Adoption of microalgae-sourced products depends on the economic feasibility. In the case of fatty acids, it is crucial to obtain high lipid yield, especially in the form of storage lipids (TAGs). However, the production of these lipids often comes into competition with the microalgae biomass, resulting in a decrease in growth. A microalgae culture integration project was conducted in an industrial park in Canada in order to cultivate microalgae from park's wastewaters and then obtain products from the biomass. Different deficiencies and stresses were tested to evaluate what condition allowed the induction of the highest lipids accumulation without compromising the growth of microalgae. The results showed that the medium controlled to pH 7.0 allowed reaching the largest amount of extracted lipids (28 ±â€¯4.3%). Companies involved in this project could be able to make significant savings by the reduced wastewater treatment costs and by not adding expensive nutrients in culture.


Assuntos
Lipídeos/biossíntese , Microalgas , Águas Residuárias , Bactérias , Biocombustíveis , Biomassa , Canadá
9.
Biotechnol Biofuels ; 11: 144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29796085

RESUMO

BACKGROUND: Pretreatment of lignocellulosic biomass (LCB) is a key step for its efficient bioconversion into ethanol. Determining the best pretreatment and its parameters requires monitoring its impacts on the biomass material. Here, we used fluorescent protein-tagged carbohydrate-binding modules method (FTCM)-depletion assay to study the relationship between surface-exposed polysaccharides and enzymatic hydrolysis of LCB. RESULTS: Our results indicated that alkali extrusion pretreatment led to the highest hydrolysis rates for alfalfa stover, cattail stems and flax shives, despite its lower lignin removal efficiency compared to alkali pretreatment. Corn crop residues were more sensitive to alkali pretreatments, leading to higher hydrolysis rates. A clear relationship was consistently observed between total surface-exposed cellulose detected by the FTCM-depletion assay and biomass enzymatic hydrolysis. Comparison of bioconversion yield and total composition analysis (by NREL/TP-510-42618) of LCB prior to or after pretreatments did not show any close relationship. Lignin removal efficiency and total cellulose content (by NREL/TP-510-42618) led to an unreliable prediction of enzymatic polysaccharide hydrolysis. CONCLUSIONS: Fluorescent protein-tagged carbohydrate-binding modules method (FTCM)-depletion assay provided direct evidence that cellulose exposure is the key determinant of hydrolysis yield. The clear and robust relationships that were observed between the cellulose accessibility by FTCM probes and enzymatic hydrolysis rates change could be evolved into a powerful prediction tool that might help develop optimal biomass pretreatment strategies for biofuel production.

10.
Ecotoxicology ; 23(2): 260-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24395509

RESUMO

Lyngbya wollei is a benthic filamentous cyanobacterium that produces a toxin analogous to the neurotoxic saxitoxin known as lyngbyatoxin (LYNGTX). Microcystis aeruginosa form blooms in the pelagic area of eutrophic lakes and produce a series of potent hepatotoxins-microcystins (MCYST). The aim of this study in vitro study was to examine the difference between the crude extracts of either M. aeruginosa or L. wollei toward the immune system of Elliptio complanata mussels. Freshly isolated hemolymph was plated and exposed to the crude extract of each species at LYNGTX or MCYST equivalent concentrations of 5, 10 and 25 µg/L for 18 h. Immunocompetence was characterized by following changes in hemocyte numbers, metabolic activity (viability), and phagocytosis. Hemocyte counts were not affected, indicating no turnover of hemocytes. Hemocyte metabolic activity was higher in cells exposed to crude extracts of L. wollei. Exposure to L. wollei extracts led to decreased pro-inflammatory precursors such as reactive oxygen species (ROS) and cyclooxygenase (COX) activities. Phagocytosis increased at 25 µg/L for both types of crude extracts. However, hemocytes exposed to crude extracts of M. aeruginosa produced more ROS and COX compared to hemocytes exposed to crude extracts of L. wollei. In conclusion, the data suggest that the crude extract of M. aeruginosa was more toxic than crude extract of L. wollei to mussel hemocytes.


Assuntos
Bivalves/efeitos dos fármacos , Misturas Complexas/toxicidade , Cianobactérias/química , Água Doce/química , Hemócitos/efeitos dos fármacos , Microcystis/química , Animais , Bivalves/metabolismo , Monitoramento Ambiental , Hemócitos/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Microcistinas/toxicidade , Fagocitose/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
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