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1.
World J Microbiol Biotechnol ; 39(4): 91, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36752862

RESUMO

Microorganisms isolated from contaminated areas play an important role in bioremediation processes. They promote heavy metal removal from the environment by adsorbing ions onto the cell wall surface, accumulating them inside the cells, or reducing, complexing, or precipitating these substances in the environment. Microorganism-based bioremediation processes can be highly efficient, low-cost and have low environmental impact. Thus, the present study aimed to select Pb2+-resistant bacteria and evaluate the growth rate, biological activity, and the presence of genes associated with metal resistance. Serratia marcescens CCMA 1010, that was previously isolated from coffee processing wastewater, was selected since was able to growth in Pb2+ concentrations of up to 4.0 mM. The growth rate and generation time did not differ from those of the control (without Pb2+), although biological activity decreased in the first hour of exposure to these ions and stabilized after this period. The presence of the zntR, zntA and pbrA genes was analysed, and only zntR was detected. The zntR gene encodes a protein responsible for regulating the production of ZntA, a transmembrane protein that facilitates Pb2+ extrusion out of the cell. S. marcescens CCMA 1010 demonstrated a potential for use as bioindicator that has potential to be used in bioremediation processes due to its resistance to high concentrations of Pb2+, ability to grow until 24 h of exposure, and possession of a gene that indicates the existence of mechanisms associated with resistance to lead (Pb2+).


Assuntos
Metais Pesados , Purificação da Água , Cádmio/metabolismo , Serratia marcescens/genética , Serratia marcescens/metabolismo , Chumbo/metabolismo , Metais Pesados/metabolismo , Íons/metabolismo , Biodegradação Ambiental
2.
Lasers Med Sci ; 37(1): 619-625, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33860864

RESUMO

The purpose of this study is to evaluate the effects of radiofrequency (RF) on sagging skin. This is a case series study with five volunteers who received a single application of capacitive RF (BTL-6000 TR-Therapy Pro®) in the right infraumbilical abdominal region, with epidermal temperature above 40°C, for 10 min (2 min per applicator area), and the skin of the contralateral region was used as control. After 30 days, on average, the skin of the abdominal region was collected for histological analysis and stained with hematoxylin and eosin, Picro-sirus, and Verhoff. The percentage of collagen and elastic fibers found was marked by the Image J®. The statistical analysis was performed in the SPSS program (version 20), with a significance level of 95%. This was registered with the ethics and research comitee of UFTM n 3.461.688 on Jul 12, 2019 and clinical trial registration n. NCT04182542, retrospectively registered. Morphometric analysis demonstrated a remodeling of collagen and elastic fibers on the side treated with RF; however, the morphometry for collagen showed no significant difference, with an average percentage of 60.94 ± 0.32 for the control side and 61.97 ± 2.80 for the treated with p=0.32. Similarly, elastic fibers also showed no significant difference between groups, with a mean percentage of 5.67 ± 2.70 for control and 6.21 ± 2.01 for treated with p=0.19. The RF with the parameters used in this study was able to cause morphological changes in collagen and elastic fibers of the abdominal region skin; however, it showed no change in the percentage of these fibers.


Assuntos
Tecido Elástico , Pele , Colágeno , Derme , Humanos , Ondas de Rádio
3.
Microbiology (Reading) ; 167(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33656438

RESUMO

The compound 17α-ethinylestradiol (EE2) is a synthetic oestrogen which is classified as a group 1 carcinogen by the World Health Organization. Together with other endocrine disruptor compounds, EE2 has been included in the surface water Watch List by the European Commission, since it causes severe adverse effects in ecosystems. Thus, it became a high priority to find or improve processes such as biodegradation of EE2 to completely remove this drug from the wastewater treatment plants (WWTPs). The present study aimed at the isolation of bacteria capable of degrading EE2 using environmental samples, namely a sludge from the Faro Northwest WWTP. Four isolates with ability to grow in the presence of 50 mg l-1 EE2 were obtained. The analysis of 16SrRNA gene sequences identified the isolated bacteria as Acinetobacter bouvetii, Acinetobacter kookii, Pantoea agglomerans and Shinella zoogloeoides. The results of biodegradation assays showed that Acinetobacter bouvetii, Acinetobacter kookii, Pantoea agglomerans and Shinella zoogloeoides were able to degrade 47±4 %, 55±3 %, 64±4% and 35±4 %, respectively of 13 mg l-1 EE2 after 168 h at 28 °C. To the best of our knowledge, these bacterial isolates were identified as EE2 degraders for the first time. In a preliminary experiment on the identification of metabolic products resulting from EE2 degradation products such as estrone (E1), γ-lactone compounds, 2-pentanedioic acid and 2-butenedioic acid an intermediate metabolite of the TCA cycle, were detected.


Assuntos
Acinetobacter/metabolismo , Estrogênios/metabolismo , Etinilestradiol/metabolismo , Pantoea/metabolismo , Rhizobiaceae/metabolismo , Esgotos/microbiologia , Poluentes Químicos da Água/metabolismo , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Biodegradação Ambiental , Pantoea/genética , Pantoea/isolamento & purificação , Rhizobiaceae/genética , Rhizobiaceae/isolamento & purificação
4.
Biometals ; 34(4): 761-793, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33961184

RESUMO

Rapid industrial development is responsible for severe problems related to environmental pollution. Many human and industrial activities require different metals and, as a result, great amounts of metals/heavy metals are discharged into the water and soil making them dangerous for both human and ecosystems and this is being aggravated by intensive demand and utilization. In addition, compounds with metal binding capacities are needed to be used for several purposes including in activities related to the removal and/or recovery of metals from effluents and soils, as metals' corrosion inhibitors, in the synthesis of metallic nanoparticles and as metal related pharmaceuticals, preferably a with minimum risks associated to the environment. Plants are able to synthesize an uncountable number of compounds with numerous functions, including compounds with metal binding capabilities. In fact, some of the plants' secondary metabolites can bind to various metals through different mechanisms, as such they are excellent sources of such compounds due to their high availability and vast diversity. In addition, the use of plant-based compounds is desirable from an environmental and economical point of view, thus being potential candidates for utilization in different industrial activities, replacing conventional physiochemical methods. This review focuses on the ability of some classes of compounds that can be found in relatively high concentrations in plants, having good metal binding capacities and thus with potential utilization in metal based industrial activities and that can be involved in the progressive development of new environmentally friendly strategies.


Assuntos
Metais Pesados/metabolismo , Plantas/metabolismo , Biodegradação Ambiental , Humanos , Resíduos Industriais , Metais Pesados/química , Plantas/química
5.
Anaerobe ; 68: 102356, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33766774

RESUMO

Fluoxetine (FLX), an antidepressant extensively used worldwide is considered an emerging pollutant. The present work intends to investigate for the first time the capacity of a bacterial community containing sulphate-reducing bacteria (SRB) enriched from an anaerobic sludge to biodegrade and use FLX as sole carbon source, since current literature suggests that this drug is poorly biodegraded being mainly removed by adsorption to sediments, where it persists. FLX was biodegraded under sulphate reducing conditions until reaching its lowest and reliably detectable concentration, when 20 mg/L of the drug was used as sole carbon source, while 66 ± 9% of 50 mg/L FLX was removed, after 31 days. The initial bacterial population was mainly constituted by Desulfomicrobium and Desulfovibrio whereas during the experiments using FLX as unique carbon source a clear shift occurred with the increase of vadinBC27 wastewater-sludge group, Macellibacteroidetes, Dethiosulfovibrio, Bacteroides, Tolumonas, Sulfuricurvum, f_Enterobacteriaceae_OTU_18 that are assumed for the first time as FLX degrading bacteria. Although the main mechanism of FLX removal described in literature is by adsorption, in the results herein presented anaerobic biodegradation appears to play the main role in the removal of the FLX, thus demonstrating the potentialities that the anaerobic processes can play in wastewater treatment aiming the removal of new emerging compounds.


Assuntos
Antidepressivos/metabolismo , Bactérias/metabolismo , Fluoxetina/metabolismo , Anaerobiose , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Sulfatos/metabolismo , Águas Residuárias/microbiologia
6.
Extremophiles ; 24(6): 809-819, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32888054

RESUMO

The microbial communities in mining impacted areas rely on a variety of mechanisms to survive in such extreme environments. In this work, a meta-taxonomic approach using 16S rRNA gene sequences was used to investigate the prokaryotic diversity of sediment samples from water bodies affected by acid mine drainage at the São Domingos mining area in the south of Portugal. Samples were collected in summer and winter from the most contaminated sites from where the water flows downstream to the freshwater of Chança's river reservoir. The prokaryotic diversity on water bodies' sediments allowed us to distinguish the highly contaminated sites (pH ≈ 2) from sites with intermediate levels of contamination (pH ≈ 3-6.5), and from sites without contamination (pH ≈ 7.5). The abundances of acidophiles of genera Acidiphilium, Acidibacter, Acidobacterium and Acidocella in the sediments were correlated with the level of acid mine drainage contamination. The two first genera were among the 30 most abundant prokaryotes in all contaminated samples, including one (SS2w), where the contamination was very diluted, thereby emphasizing the impact that such type of pollution can have in the microbial communities of sediments. In addition, the high abundances of archaeal taxa from class Thermoplasmata and of bacteria from family RCP1-48 in the sediments from the most contaminated site corroborate their importance in such ecosystems and a putative role in the generation of acid mine drainage.


Assuntos
Archaea/classificação , Bactérias/classificação , Sedimentos Geológicos/microbiologia , Mineração , Rios/microbiologia , Poluentes Químicos da Água , Ácidos , Portugal , RNA Ribossômico 16S/genética
7.
Appl Microbiol Biotechnol ; 100(6): 2721-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26590590

RESUMO

The 16S ribosomal RNA (rRNA) gene has been the most commonly used sequence to characterize bacterial communities. The classical approach to obtain gene sequences to study bacterial diversity implies cloning amplicons, selecting clones, and Sanger sequencing cloned fragments. A more recent approach is direct sequencing of millions of genes using massive parallel technologies, allowing a large-scale biodiversity analysis of many samples simultaneously. However, currently, this technique is still expensive when applied to few samples; therefore, the classical approach is still used. Recently, we found a community able to remove 50 mg/L Pd(II). In this work, aiming to identify the bacteria potentially involved in Pd(II) removal, the separation of urea/heat-denatured DNA fragments by urea-agarose gel electrophoresis was applied for the first time to select 16S rRNA-cloned amplicons for taxonomic studies. The major raise in the percentage of bacteria belonging to genus Clostridium sensu stricto from undetected to 21 and 41 %, respectively, for cultures without, with 5 and 50 mg/L Pd(II) accompanying Pd(II) removal point to this taxa as a potential key agent for the bio-recovery of this metal. Despite sulfate-reducing bacteria were not detected, the hypothesis of Pd(II) removal by activity of these bacteria cannot be ruled out because a slight decrease of sulfate concentration of the medium was verified and the formation of PbS precipitates seems to occur. This work also contributes with knowledge about suitable partial 16S rRNA gene regions for taxonomic studies and shows that unidirectional sequencing is enough when Sanger sequencing cloned 16S rRNA genes for taxonomic studies to genus level.


Assuntos
Bactérias/metabolismo , Eletroforese em Gel de Ágar/métodos , Poluentes Ambientais/metabolismo , Metagenômica/métodos , Desnaturação de Ácido Nucleico , Paládio/metabolismo , Ureia , Bactérias/classificação , Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Appl Microbiol Biotechnol ; 100(19): 8283-302, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27550218

RESUMO

There have been extensive and comprehensive reviews in the field of metal sulfide precipitation in the context of environmental remediation. However, these works have focused mainly on the removal of metals from aqueous solutions-usually, metal-contaminated effluents-with less emphasis on the precipitation process and on the end-products, frequently centering on metal removal efficiencies. Recently, there has been an increasing interest not only in the possible beneficial effects of these bioremediation strategies for metal-rich effluents but also on the formed precipitates. These metal sulfide materials are of special relevance in industry, due to their optical, electronic, and mechanical properties. Hence, identifying new routes for synthesizing these materials, as well as developing methodologies allowing for the control of the shape and size of particulates, is of environmental, economic, and practical importance. Multiple studies have shown proof-of-concept for the biological synthesis of inorganic metallic sulfide nanoparticles (NPs), resorting to varied organisms or cell components, though this information has scarcely been structured and compiled in a systematic manner. In this review, we overview the biological synthesis methodologies of nanosized metal sulfides and the advantages of these strategies when compared to more conventional chemical routes. Furthermore, we highlight the possibility of the use of numerous organisms for the synthesis of different metal sulfide NPs, with emphasis on sulfate-reducing bacteria (SRB). Finally, we put in perspective the potential of these methodologies in the emerging research areas of biohydrometallurgy and nanobiotechnology for the uptake of metals in the form of metal sulfide nanoparticles. A more complete understanding of the principles underlying the (bio)chemistry of formation of solids in these conditions may lead to the large-scale production of such metal sulfides, while simultaneously allowing an enhanced control over the size and shape of these biogenic nanomaterials.


Assuntos
Biotecnologia/métodos , Nanopartículas Metálicas , Semicondutores , Sulfetos/metabolismo , Bactérias/metabolismo , Biotecnologia/tendências , Precipitação Química
9.
Food Chem ; 453: 139605, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38788641

RESUMO

Minerals are reported to dominate the electrical properties of honey and indicate its botanical and geographical origins. In this study, Electrochemical Impedance Spectroscopy (EIS) was used to assess the relation between mineral elements, electrical properties and botanical origin using three honey varieties - Citrus sp., Eucalyptus sp., and Erica sp. These varieties are identified through pollen analysis and market labelling. Flame atomic absorption and emission spectroscopies were used to quantify the concentrations of eight elements (potassium, sodium, calcium, magnesium, manganese, zinc, copper, and iron). Among all the mineral elements, potassium showed a consistent correlation with impedance. The potassium estimation in honey and standard solutions (calibration curve) had similar sensitivities of 153.43 nF/mM and 132.68 nF/mM, respectively. Additionally, the analysis revealed that potassium dominates the mineral composition, with the other species present in minimal quantities. The EIS technique showed high sensitivity to potassium and other ionisable species, making it possible to classify the botanical origin of these three honey types. The EIS technique proved to be both time and cost effective, yielding a classification rate higher than that achieved by analysing mineral composition.


Assuntos
Espectroscopia Dielétrica , Mel , Potássio , Mel/análise , Mel/classificação , Potássio/análise , Citrus/química , Citrus/classificação
10.
Antibiotics (Basel) ; 13(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38534665

RESUMO

Although the plants of the genus Euphorbia are largely exploited by therapists in Morocco, the composition and antibacterial activities of propolis from these plants are still unknown. To address this gap, this study aimed to characterize the pollen type, the volatile compounds, and the phenolic and mineral profiles of three Euphorbia propolis samples collected in Morocco and evaluate their antimicrobial activities. The minimum inhibitory concentration of the propolis samples was determined by the microdilution method, and the anti-adherence activity was evaluated by the crystal violet assay. The examination of anti-quorum-sensing proprieties was performed using the biosensor Chromobacterium violaceum CV026. Pollen analysis revealed that Euphorbia resinifera pollen dominated in the P1 sample (58%), while E. officinarum pollen dominated in the P2 and P3 samples (44%). The volatile compounds were primarily composed of monoterpene hydrocarbons, constituting 35% in P1 and 31% in P2, with α-pinene being the major component in both cases, at 16% in P1 and 15% in P2. Calcium (Ca) was the predominant mineral element in both E. resinifera (P1) and E. officinarum (P2 and P3) propolis samples. Higher levels of phenols, flavonoids and dihydroflavonoids were detected in the E. officinarum P2 sample. The minimum inhibitory concentration (MIC) value ranged from 50 to 450 µL/mL against Gram-positive and Gram-negative bacteria. Euphorbia propolis displayed the ability to inhibit quorum sensing in the biosensor C. violaceum CV026 and disrupted bacterial biofilm formation, including that of resistant bacterial pathogens. In summary, the current study evidences the potential use of E. officinarum propolis (P2 and P3) to combat important features of resistant pathogenic bacteria, such as quorum sensing and biofilm formation.

11.
J Environ Manage ; 128: 226-32, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23747373

RESUMO

This work describes the synthesis of CuS powders in high yield and via an environmentally friendly and straightforward process, under ambient conditions (temperature and pressure), by adding to aqueous copper (II) a nutrient solution containing biologically generated sulfide from sulfate-reducing bacteria (SRB). The powders obtained were composed of CuS (covellite) nanoparticles (NPs) exhibiting a spheroid morphology (<5 nm). The relevance of this method to obtain CuS supported solid substrates has been demonstrated by performing the synthesis in the presence of TiO2 and SiO2 submicron particles. We further extended the work carried out, which substantiates the potential of using biogenic sulfide for the production of covellite nanocrystals and composites, using the effluent of a bioremediation column. Hence, such process results in the synthesis of added value products obtained from metal rich effluents, such as metallurgical and industrial ones, or Acid Mine Drainage (AMD), when associated with bioremediation processes.


Assuntos
Biodegradação Ambiental , Cobre/química , Nanopartículas/química , Cobre/isolamento & purificação , Desulfovibrio desulfuricans/metabolismo , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Dióxido de Silício , Titânio , Difração de Raios X
12.
Adv Rheumatol ; 63(1): 41, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596632

RESUMO

BACKGROUND: Takayasu's arteritis (TA) is a vasculitis that affects the aorta and its branches and causes stenosis, occlusion, and aneurysms. Up to 60% of TA patients are associated with cardiac involvement which confers a poor prognosis. Global longitudinal strain (GLS) analysis is an echocardiographic technique that can detect the presence of subclinical systolic dysfunction. Hence, this study aimed to describe the prevalence of subclinical systolic dysfunction in patients with TA using the GLS method and to correlate this finding with disease activity using the ITAS-2010 (Indian Takayasu Activity Score). METHODS: Thirty patients over 18 years of age who met the American College of Rheumatology (ACR) 1990 criteria for TA were included. The sample was submitted for medical record review, clinical and echocardiographic evaluation, and application of ITAS-2010. The cutoff for systolic dysfunction was GLS > - 20%. RESULTS: Of the 30 patients analyzed, 25 (83.3%) were female, and the mean age was 42.6 years (± 13.2). The median time since diagnosis was 7.5 years [range, 3-16.6 years], and the type V angiographic classification was the most prevalent (56.7%). Regarding echocardiographic findings, the median ejection fraction (EF) was 66% [61-71%] and the GLS was - 19.5% [-21.3 to -15.8%]. Although half of the participants had reduced GLS, only two had reduced EF. Eleven patients (33.%) met the criteria for activity. An association was found between disease activity and reduced GLS in eight patients (P = 0.02) using the chi-square test. CONCLUSION: GLS seems to be an instrument capable of the early detection of systolic dysfunction in TA. The association between GLS and disease activity in this study should be confirmed in a study with a larger sample size.


Assuntos
Arterite de Takayasu , Humanos , Feminino , Adolescente , Adulto , Masculino , Arterite de Takayasu/diagnóstico por imagem , Arterite de Takayasu/epidemiologia , Estudos Transversais , Prevalência , Constrição Patológica , Ecocardiografia
13.
Biodegradation ; 23(5): 693-703, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22367464

RESUMO

A highly Al-resistant dissimilatory sulphate-reducing bacteria community was isolated from sludge of the wetland of Urgeiriça mine (community W). This community showed excellent sulphate removal at the presence of Al³âº. After 27 days of incubation, 73, 86 and 81% of sulphate was removed in the presence of 0.48, 0.90 and 1.30 mM of Al³âº, respectively. Moreover, Al³âº was simultaneously removed: 55, 85 and 78% of metal was removed in the presence of 0.48, 0.90 and 1.30 mM of Al³âº, respectively. The dissociation of aluminium-lactate soluble complexes due to lactate consumption by dissimilatory sulphate-reducing bacteria can be responsible for aluminum removal, which probably precipitates as insoluble aluminium hydroxide. Phylogenetic analysis of 16S rRNA gene showed that this community was mainly composed by bacteria closely related to Desulfovibrio desulfuricans. However, bacteria affiliated to Proteus and Ralstonia were also present in the community.


Assuntos
Alumínio/isolamento & purificação , Alumínio/toxicidade , Bactérias/metabolismo , Sulfatos/isolamento & purificação , Sulfatos/metabolismo , Bactérias/citologia , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental/efeitos dos fármacos , Precipitação Química , Consórcios Microbianos/efeitos dos fármacos , Dados de Sequência Molecular , Oxirredução/efeitos dos fármacos , Filogenia , Polimorfismo de Fragmento de Restrição , Sulfetos/toxicidade , Eliminação de Resíduos Líquidos
14.
Mar Pollut Bull ; 185(Pt A): 114251, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36330933

RESUMO

The biodegradability conditions for both, petroleum-based plastics and bioplastics needs to be evaluated under environmentally realistic conditions. We assessed the biodegradability of low-density polyethylene and biobased polyethylene terephthalate microplastic films by a consortium of marine bacteria during 45 days. Bacterial growth and pH were higher in the samples inoculated with bacteria, compared to the controls. Fourier Infrared spectroscopy-Attenuated Total Reflectance and scanning electron microscopy indicated changes in the chemical functional groups, and the presence of fractures and biofilms in the surface of both plastics exposed to the bacterial community, respectively. The chemical oxygen demand further indicated signs of biodegradation of both polymers. Specific groups of bacteria showed preference for each type of microplastic. Overall, our results show signs of biodegradation, or at least biodeterioration and biofragmentation, of both types of plastics, when subjected to the selected bacterial community. Biobased PET was no more prone to biodegradation than conventional, petroleum-based LDPE.


Assuntos
Petróleo , Poluentes Químicos da Água , Microplásticos , Plásticos , Biodegradação Ambiental , Bactérias/metabolismo , Polietileno/metabolismo , Poluentes Químicos da Água/análise
15.
Sci Total Environ ; 811: 151359, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-34742963

RESUMO

The metabolism of contemporary industrialized societies, that is their energy and material flows, leads to the overconsumption and waste of natural resources, two factors often disregarded in the global ecological equation. In this Discussion article, we examine the amount of natural resources that is increasingly being consumed and wasted by humanity, and propose solutions to reverse this pattern. Since the beginning of the 20th century, societies, especially from industrialized countries, have been wasting resources in different ways. On one hand, the metabolism of industrial societies relies on non-renewable resources. On the other hand, yearly, we directly waste or mismanage around 78% of the total water withdrawn, 49% of the food produced, 31% of the energy produced, 85% of ores and 26% of non-metallic minerals extracted, respectively. As a consequence, natural resources are getting depleted and ecosystems polluted, leading to irreversible environmental changes, biological loss and social conflicts. To reduce the anthropogenic footprint in the planet, and live in harmony with other species and ourselves, we suggest to shift the current economic model based on infinite growth and reduce inequality between and within countries, following a degrowth strategy in industrialized countries. Public education to reduce superfluous consumption is also necessary. In addition, we propose a set of technological strategies to improve the management of natural resources towards circular economies that, like ecosystems, rely only upon renewable resources.


Assuntos
Ecossistema , Recursos Naturais , Conservação dos Recursos Naturais , Tecnologia
16.
Foods ; 10(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34441685

RESUMO

Honey is a natural food product very famous for its health benefits for being an important source of antioxidant and phenolic compounds. Euphorbia honeys obtained from different regions of Morocco were evaluated for their ability to inhibit acetylcholinesterase, lipoxygenase, tyrosinase and xanthine oxidase activities. Their antioxidant properties were evaluated using the: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity, nitric oxide scavenging activity (NO) and scavenging ability of superoxide anion radical. Then, the phenolic extracts of the same entire honey samples were evaluated by liquid chromatography coupled to diode array detection and mass spectrometry (LC-DAD-MS) and tested for the biological activities previously evaluated on the entire honeys, in order to conduct a comparative study between both (honey and phenolic extracts). The chromatographic profiles for the studied Euphorbia honey extracts were different. Phenolic compounds gallic acid, 4-hydroxybenzoic acid and p-coumaric acid were detected in all samples, whereas kampferol was only present in two samples. Physicochemical parameters and total phenolic content were also determined. Entire honey that recorded the highest rate of phenols was sample M6 (E. resinifera) = 69.25 mg GAE/100 g. On the other hand, the phenolic extracts had better antioxidant and enzyme inhibitory activities than the entire honeys, regardless the monofloral honey type. In conclusion, the studied Euphorbia honeys may have a great potential as antioxidant, anti-inflammatory and anti-tyrosinase sources for pharmaceutical and cosmetic applications.

17.
Environ Technol ; 41(18): 2293-2304, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30605363

RESUMO

The recycling of scarce elements such as platinum-group metals is becoming crucial due to their growing importance in current and emerging applications. In this sense, the recovery of palladium and rhodium from a spent auto-catalyst by leaching in HCl/CuCl2 media was studied, aiming at assessing the kinetic performance as well as the influence of some processing factors, and the behaviour of contaminant metals. Based on a kinetic model developed for the present case, the influence of temperature was evaluated and the corresponding values of activation energy were estimated as 60.1 ± 4.1 kJ mol-1 for Pd and 44.3 ± 7.3 kJ mol-1 for Rh, indicating the relevance of the chemical step rather than diffusion. This finding was corroborated by the non-significant influence of the stirring velocity. The reaction orders were estimated for each leaching reagent: for HCl, values of 2.1 ± 0.1 for Pd and 1.0 ± 0.3 for Rh were obtained; for Cu2+, the obtained values were 0.42 ± 0.04 for Pd and 0.36 ± 0.06 for Rh. Without any significant loss of efficiency, solutions with higher metal concentrations were obtained using lower liquid/solid ratios, such as 5 L/kg. The main contaminant in solution was aluminum, and its leaching was found to be very dependent on the temperature and acid concentration.


Assuntos
Paládio , Ródio , Catálise , Cinética , Reciclagem
18.
Biodegradation ; 20(4): 559-67, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19137404

RESUMO

Biological treatment with dissimilatory sulphate-reducing bacteria has been considered the most promising alternative for decontamination of sulphate rich effluents. These wastewaters are usually deficient in electron donors and require their external addition to achieve complete sulphate reduction. The aim of the present study was to investigate the possibility of using food industry wastes (a waste from the wine industry and cheese whey) as carbon sources for dissimilatory sulphate-reducing bacteria. The results show that these wastes can be efficiently used by these bacteria provided that calcite tailing is present as a neutralizing and buffer material. A 95 and 50 % sulphate reduction was achieved within 20 days of experiment by a consortium of dissimilatory sulphate-reducing bacteria grown on media containing waste from the wine industry or cheese whey respectively. Identification of the dissimilatory sulphate-reducing bacteria community using the dsr gene revealed the presence of the species Desulfovibrio fructosovorans, Desulfovibrio aminophilus and Desulfovibrio desulfuricans. The findings of the present study emphasise the potential of using wastes from the wine industry as carbon source for dissimilatory sulphate-reducing bacteria, combined with calcite tailing, in the development of cost effective and environmentally friendly bioremediation processes.


Assuntos
Carbono/metabolismo , Indústria Alimentícia , Resíduos Industriais , Sulfatos/metabolismo , Sequência de Bases , Queijo , Primers do DNA , Lactatos/metabolismo , Filogenia , Reação em Cadeia da Polimerase
19.
Open Forum Infect Dis ; 6(12): ofz520, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31867405

RESUMO

BACKGROUND: Community-acquired pneumonia (CAP) is the leading cause of death in children. Identification of reliable biomarkers offers the potential to develop a severity quantitative score to assist in clinical decision-making and improve outcomes. METHODS: A systematic review and meta-analysis was performed in PubMed and EMBASE on November 13, 2018, to examine the association between host inflammatory biomarkers and CAP severity in children. The inclusion criteria were case-control, cross-sectional, and cohort studies that examined candidate serum biomarkers. We extracted outcomes of interest, means, and standardized mean differences (SMDs) of plasma and serum levels of biomarkers together with information on disease severity. Meta-analysis was performed. This review was registered in the PROSPERO international registry (CRD42019123351). RESULTS: Two hundred seventy-two abstracts were identified, and 17 studies were included. Among the biomarkers evaluated, levels of C-reactive protein (CRP; SMD, 0.63; 95% confidence interval [CI], 0.35 to 0.91), interleukin (IL)-6 (SMD, 0.46; 95% CI, 0.25 to 0.66), IL-8 (SMD, 0.72; 95% CI, 0.15 to 1.29), neutrophil count (SMD, 0.27; 95% CI, 0.07 to 0.47), and procalcitonin (SMD, 0.68; 95% CI, 0.20 to 1.15) were substantially increased in severe CAP. In contrast, IL-2 concentrations (SMD, -0.24; 95% CI, -0.45 to -0.03) were higher in nonsevere CAP. Study heterogeneity was reported to be high (I 2 > 75%), except for IL-2, IL-5, IL-6, and IL-12p70, which were classified as moderate (I 2 = 50%-74%). Only neutrophil and white blood cell counts were described by studies exhibiting a low level of heterogeneity. CONCLUSIONS: Our results suggest that host biomarkers, and especially CRP, IL-6, IL-8, and procalcitonin levels, have the potential to predict severe CAP in pediatric populations.

20.
Adv Rheumatol ; 63: 41, 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1513559

RESUMO

Abstract Background Takayasu's arteritis (TA) is a vasculitis that affects the aorta and its branches and causes stenosis, occlusion, and aneurysms. Up to 60% of TA patients are associated with cardiac involvement which confers a poor prognosis. Global longitudinal strain (GLS) analysis is an echocardiographic technique that can detect the presence of subclinical systolic dysfunction. Hence, this study aimed to describe the prevalence of subclinical systolic dysfunction in patients with TA using the GLS method and to correlate this finding with disease activity using the ITAS-2010 (Indian Takayasu Activity Score). Methods Thirty patients over 18 years of age who met the American College of Rheumatology (ACR) 1990 criteria for TA were included. The sample was submitted for medical record review, clinical and echocardiographic evaluation, and application of ITAS-2010. The cutoff for systolic dysfunction was GLS > - 20%. Results Of the 30 patients analyzed, 25 (83.3%) were female, and the mean age was 42.6 years (± 13.2). The median time since diagnosis was 7.5 years [range, 3-16.6 years], and the type V angiographic classification was the most prevalent (56.7%). Regarding echocardiographic findings, the median ejection fraction (EF) was 66% [61-71%] and the GLS was - 19.5% [-21.3 to -15.8%]. Although half of the participants had reduced GLS, only two had reduced EF. Eleven patients (33.%) met the criteria for activity. An association was found between disease activity and reduced GLS in eight patients (P = 0.02) using the chi-square test. Conclusion GLS seems to be an instrument capable of the early detection of systolic dysfunction in TA. The association between GLS and disease activity in this study should be confirmed in a study with a larger sample size.

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