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1.
Sci Total Environ ; 783: 147494, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34088122

RESUMO

Heavy metals are considered major environmental pollutants. Soil microorganisms represent a predominant component of soils ecosystems, yet there is little information regarding hormetic responses of soil microorganisms to single and combined exposures to heavy metals. In the present study, to explore and predict the hormetic response of soil microorganisms, dose-response relationships of bacterial and fungal populations to single and combined treatments of cadmium (Cd) and lead (Pb) were evaluated. The results revealed hormetic responses of bacterial and fungal populations to both single and combined Cd and Pb treatments. The maximum stimulation (Mmax; relative to control treatment with no metals) of bacterial and fungal populations was 40% at 2 mg Cd/kg and 60% at 160 mg Pb/kg. An enhanced Mmax occurred in bacterial (50%) and fungal (75%) populations in the presence of the binary mixtures of 0.6 mg Cd/kg + 160 mg Pb/kg and 4.0 mg Cd/kg + 200 mg Pb/kg, suggesting positive additivity. This study showed that the hormetic effects of the mixtures were related to the independent effect of Cd and Pb, but they could not be predicted by the single effect of Cd or Pb. These new findings of the hormetic response of soil microorganisms to single treatments of Cd and Pb and their binary mixtures can facilitate the determination and minimization of ecological risks in heavy metal-polluted soils.


Assuntos
Metais Pesados , Poluentes do Solo , Bactérias , Cádmio/toxicidade , Ecossistema , Fungos , Hormese , Chumbo/toxicidade , Metais Pesados/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
2.
Sheng Wu Gong Cheng Xue Bao ; 37(5): 1637-1658, 2021 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-34085447

RESUMO

Filamentous fungi are important industrial microorganisms that play important roles in the production of bio-based products such as organic acids, proteins and secondary metabolites. The development of metabolic engineering and its enabling techniques have greatly promoted the design, construction and application of filamentous fungal cell factories. This article systematically reviews the development of filamentous fungal cell factories constructed through metabolic engineering, and discusses the challenges and future perspectives for systems metabolic engineering of filamentous fungi.


Assuntos
Fungos , Engenharia Metabólica , Fungos/genética
3.
Braz J Biol ; 82: e236219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076165

RESUMO

Fungi are important in several aspects of human life. In particular, to agriculture, pathogenic fungi are of great importance, as they are responsible for production losses of the most diverse types. Because of this, knowledge about pathogenic fungus is of extreme importance for farmers and professionals working in agricultural areas. Among farmers who use specific agroecological practices, this knowledge is even more valuable, since by not adopting conventional methods of production, they resort to non-invasive alternatives that are less or not harmful at all to the environment in consideration of production management methods. This study aimed to assess farmer perception in the Cerrado biome in the city of Goiás (GO), Brazil, in order to understand their ethnomycological perceptions to verify historical management practices, their knowledge about phytopathogenic fungi, and how these producers perceive fungi. We used the theoretical reference method "From peasant to peasant" formulated by ANPA - National Association of Small Farmers. Some aspects of farmers' ethnomycological knowledge are discussed. These ease identification the representatives of the Fungi Kingdom is associated with organisms that present easily recognizable characteristics, such as wood-ears or disease-causing fungi. In general, farmers are able to identify representatives of the Fungi Kingdom that are found in their daily lives. The perception of farmers about fungi, a group still much unknown by society, is very relevant for future actions of ethnomycology.


Assuntos
Agricultura , Fazendeiros , Brasil , Fungos , Humanos , Percepção
4.
Sensors (Basel) ; 21(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065526

RESUMO

A detector for identifying potential bacterial hazards in the air was designed and created in the Military Institute of Chemistry and Radiometry in the framework of the project FLORABO. The presence of fungi and bacteria in the air can affect the health of people in a given room. The need to control the amount of microorganisms, both in terms of quantity and quality, applies to both hospitals and offices. The device is based on the fluorescence spectroscopy analysis of the sample and then these results were compared to the resulting spectrogram database, which includes the standard curves obtained in the laboratory for selected bacteria. The measurements provide information about the presence, the type, and the approximate concentration of bacteria in the sample. The spectra were collected at different excitation wavelengths, and the waveforms are specific for each of the strains. It also takes under analysis the signal intensities of the different spectra (not only shape a maximum of the peak) so that the concentration of bacteria in the sample being tested can be determined. The device was tested in the laboratory with concentrations ranging from 10 to 108 cells/mL. Additionally, the detector can distinguish between the vegetative forms of spores of the bacteria.


Assuntos
Microbiologia do Ar , Fungos , Bactérias , Computadores de Mão , Monitoramento Ambiental , Hospitais
5.
Molecules ; 26(10)2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-34065753

RESUMO

The lignocellulosic biomass is comprised of three major components: cellulose, hemicellulose, and lignin. Among these three, cellulose and hemicellulose were already used for the generation of simple sugars and subsequent value-added products. However, lignin is the least applied material in this regard because of its complex and highly variable nature. Regardless, lignin is the most abundant material, and it can be used to produce value-added products such as lignin-modifying enzymes (LMEs), polyhydroxyalkanoates (PHAs), microbial lipids, vanillin, muconic acid, and many others. This review explores the potential of lignin as the microbial substrate to produce such products. A special focus was given to the different types of lignin and how each one can be used in different microbial and biochemical pathways to produce intermediate products, which can then be used as the value-added products or base to make other products. This review paper will summarize the effectiveness of lignin as a microbial substrate to produce value-added products through microbial fermentations. First, basic structures of lignin along with its types and chemistry are discussed. The subsequent sections highlight LMEs and how such enzymes can enhance the value of lignin by microbial degradation. A major focus was also given to the value-added products that can be produced from lignin.


Assuntos
Enzimas/metabolismo , Fungos/crescimento & desenvolvimento , Lignina/química , Biotransformação , Meios de Cultura/química , Fermentação , Proteínas Fúngicas/metabolismo , Fungos/metabolismo
6.
Int J Mol Sci ; 22(11)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067346

RESUMO

Prenylated flavonoids are an important class of naturally occurring flavonoids with important biological activity, but their low abundance in nature limits their application in medicines. Here, we showed the hemisynthesis and the determination of various biological activities of seven prenylated flavonoids, named 7-13, with an emphasis on antimicrobial ones. Compounds 9, 11, and 12 showed inhibitory activity against human pathogenic fungi. Compounds 11, 12 (flavanones) and 13 (isoflavone) were the most active against clinical isolated Staphylococcus aureus MRSA, showing that structural requirements as prenylation at position C-6 or C-8 and OH at positions C-5, 7, and 4' are key to the antibacterial activity. The combination of 11 or 12 with commercial antibiotics synergistically enhanced the antibacterial activity of vancomycin, ciprofloxacin, and methicillin in a factor of 10 to 100 times against drug-resistant bacteria. Compound 11 combined with ciprofloxacin was able to decrease the levels of ROS generated by ciprofloxacin. According to docking results of S enantiomer of 11 with ATP-binding cassette transporter showed the most favorable binding energy; however, more studies are needed to support this result.


Assuntos
Antibacterianos/farmacologia , Flavonoides/farmacologia , Prenilação/fisiologia , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Simulação por Computador , Flavanonas/farmacologia , Fungos/efeitos dos fármacos , Humanos , Isoflavonas/farmacologia , Camundongos , Testes de Sensibilidade Microbiana/métodos , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos
7.
Waste Manag ; 128: 64-72, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33965674

RESUMO

Large amounts of bioaerosols are generated during the treatment of landfill leachate, which poses potential threat to public health safety. In this study, the concentrations, particle size distribution, and microbial community of bioaerosols emitted from the low-pH biofilter (LPB) and neutral-pH biofilter (NPB) used to treat the odors from landfill leachate, as well as the effect of the inlet flow rate (IFR) and water-containing rate (WCR) were investigated. The results showed that the removal efficiency of the LPB for heterotrophic bacteria and the NPB for fungi were higher when the IFR was higher. The outlet concentrations (OCs) of heterotrophic bacteria, neutral sulfur bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, NO2-, and NO3- were negatively correlated with the IFR in the LPB, whereas those of fungi and acidophilic sulfur bacteria were positively correlated with the IFR. Inverse correlation between the OCs and IFR was exhibited in the NPB. The proportions of dominant microorganisms with large particle size (> 3.3 µm) reduced significantly after both the LPB and NPB, which was aggravated under higher WCR. The analysis of microbial community illustrated that the dominant heterotrophic bacteria were different, while the dominant fungi were similar in the bioaerosols between the LPB and NPB, respectively. Due to the different emission characteristics, bioaerosols in the LPB and NPB outlet should be distinguished and taken seriously.


Assuntos
Poluentes Químicos da Água , Bactérias , Reatores Biológicos , Fungos , Concentração de Íons de Hidrogênio , Odorantes
8.
Pan Afr Med J ; 38: 227, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34046132

RESUMO

Introduction: opportunistic fungal infections due to immunosuppression coupled with antifungal drug resistance are an emerging challenge globally. The present study examined the antifungal susceptibility of yeasts and molds from sputum of tuberculosis retreatment and relapse patients at selected reference facilities in Kenya. Methods: a total of 340 sputa samples from patients who gave written informed consent were examined. Fungal culture was done on sabouraud dextrose agar (SDA). Molds were identified by macroscopic and microscopic features while yeasts were inoculated on CHROMTMagar Candida and confirmed using API 20C AUXTM. Itraconazole (ICZ), voriconazole (VCZ), fluconazole (FCZ) and amphotericin B (AMB) were tested using broth micro-dilution methods according to Clinical and Laboratory Standards Institute (CLSI). Results: out of the 340 samples, 14.4% (n=49) and 15.6% (n=53) were positive for yeasts and molds respectively. Candida albicans and C. krusei were the most predominant isolates constituting 49.0% (n=24) and 20.4% (n=10) of the total yeasts respectively. Aspergillus spp. were the most frequent (22.6%) molds and isolates with MICs ≥4µg/ml on the antifungal agents were noted. All the molds except two (n=2) isolates of Scedosporium aspiopermum exhibited MICs >4µg/ml for fluconazole. Overall, molds were more sensitive to AMB and VCZ. Candida albicans had MIC50 <0.06µg/ml, and MIC90<4µg/ml. There was a statistically significant difference (F=3.7, P=0.004<0.05) in the overall sensitivity pattern of molds for the four antifungal agents while there was no significant difference (F=1.7, P=0.154>0.05) in sensitivity exhibited by the yeasts. Conclusion: the study demonstrates the significance of fungal colonization in presumptive tuberculosis retreatment or relapse with evidence of triazole resistance. There is need to strengthen fungal diagnostic and clinical management capabilities in susceptible populations.


Assuntos
Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Micoses/tratamento farmacológico , Infecções Oportunistas/tratamento farmacológico , Estudos Transversais , Farmacorresistência Fúngica , Fungos/isolamento & purificação , Humanos , Quênia , Testes de Sensibilidade Microbiana , Micoses/microbiologia , Infecções Oportunistas/microbiologia , Retratamento , Escarro/microbiologia , Tuberculose/tratamento farmacológico
9.
Sci Total Environ ; 785: 147189, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933764

RESUMO

Fire and herbivory are important natural disturbances in grassy biomes. Both drivers are likely to influence belowground microbial communities but no studies have unravelled the long-term impact of both fire and herbivory on bacterial and fungal communities. We hypothesized that soil bacterial communities change through disturbance-induced shifts in soil properties (e.g. pH, nutrients) while soil fungal communities change through vegetation modification (biomass and species composition). To test these ideas, we characterised soil physico-chemical properties (pH, acidity, C, N, P and exchangeable cations content, texture, bulk density, moisture), plant species richness and biomass, microbial biomass and bacterial and fungal community composition and diversity (using 16S and ITS rRNA amplicon sequencing, respectively) in six long-term (18 to 70 years) ecological research sites in South African savanna and grassland ecosystems. We found that fire and herbivory regimes profoundly modified soil physico-chemical properties, plant species richness and standing biomass. In all sites, an increase in woody biomass (ranging from 12 to 50%) was observed when natural disturbances were excluded. The intensity and direction of changes in soil properties were highly dependent on the topo-pedo-climatic context. Overall, fire and herbivory shaped bacterial and fungal communities through distinct driving forces: edaphic properties (including Mg, pH, Ca) for bacteria, and vegetation (herbaceous biomass and woody cover) for fungi. Fire and herbivory explained on average 7.5 and 9.8% of the fungal community variability, respectively, compared to 6.0 and 5.6% for bacteria. The relatively small changes in microbial communities due to natural disturbance is in stark contrast to dramatic vegetation and edaphic changes and suggests that soil microbial communities, having evolved with disturbance, are resistant to change. This represents both a buffer to short-term anthropogenic-induced changes and a restoration challenge in the face of long-term changes.


Assuntos
Incêndios , Herbivoria , Bactérias , Biomassa , Ecossistema , Fungos , Pradaria , Solo , Microbiologia do Solo
10.
Sci Total Environ ; 785: 147312, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33957592

RESUMO

The length and number of streams experiencing intermittency is expected to increase in response to human population growth, associated water use, and climate change. In these streams, habitat contraction may occur at distinct rates giving rise to drying periods of distinct duration. To date, the impact of drought installation rate and duration have been mostly overlooked. In this microcosm study, stream conditioned oak leaf litter was subjected to either a short (5 weeks) or a long (8 weeks) drying period, originating from a very slow, slow, or abrupt contraction. The effects of these treatments were compared at the end of the drying period in terms of microbial-mediated litter mass loss, fungal biomass, respiration, and sporulation rates. A very slow contraction pattern led to 1.3 times higher mass loss than both slow or abrupt contraction. Fungal biomass, respiration and sporulation rates were up to 2.3 times lower under slow than abrupt contraction. Both drying period durations inhibited leaf decomposition, suggesting an early, critical effect of drying on microbial-mediated processing, regardless of contraction pattern. This seems to be related to an impoverishment of leaf associated fungal communities and resultant lower functional efficacy - species richness decreased by up to 75% in response to a long (vs. short) drying period, despite the maintenance of mycelial biomass. Our results show the relevance of aquatic hyphomycetes to litter decomposition in dry streambeds, particularly following slower habitat contraction patterns. Faster wet-to-dry transitions and longer drying periods strongly impaired microbial functioning, with potential impacts on global processing rates and cascading effects through changes of detritus quality. If confirmed in field tests, such impacts on stream functioning may be mitigated by preserving riparian forests, which may protect against extreme drying events by buffering temperature changes.


Assuntos
Ecossistema , Rios , Biomassa , Florestas , Fungos , Humanos , Folhas de Planta
11.
Bioresour Technol ; 335: 125296, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34022478

RESUMO

In this study, the influence of distinct hydraulic retention times (HRT) and organic loading rates (OLRs) on fungal dynamics during food waste anaerobic digestion in immersed membrane-based bio-reactors (iMBR) were investigated. The organic loading rate 4-8 g VS/L/d (R1) and 6-10 g VS/L/d (R2) were set in two iMBR. T1 (1d), T2 (15d) and T3 (34d) samples collected from each bioreactor were analyzed fungal community by using 18s rDNA. In R2, T2 had the most abundant Ascomycota, Basidiomycota, Chytridiomycota and Mucoromycota. As for R1, T3 also had the richest Cryptomycota except above four kinds of fungi. Subsequently, the Principal Component Analysis (PCA) and Non-Metric Multi-Dimensional Scaling (NMDS) indicated that fungal diversity was varied among the all three phases (T1, T2, and T3) and each treatment (R1 and R2). Finally, the results showed that different OLRs and HRT have significantly influenced the fungal community.


Assuntos
Eliminação de Resíduos , Esgotos , Anaerobiose , Reatores Biológicos , Alimentos , Fungos , Metano
12.
J Hazard Mater ; 414: 125553, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030410

RESUMO

The environmental biodegradability profile of graphene related materials (GRMs) is important to know in order to predict whether these materials will accumulate in soil or will be transformed by primary decomposers. In this study, few-layer graphene (FLG) was exposed to living and devitalized axenic cultures of two white-rot basidiomycetes (Bjerkandera adusta and Phanerochaete chrysosporium) and one soil saprotrophic ascomycete (Morchella esculenta) with or without lignin, for a period of four months. Over this time, the increase of fungal biomass and presence of H2O2 and oxidizing enzymes [laccase/peroxidase and lignin peroxidase (LiP)] in growth media was assessed by gravimetric and spectrophotometric measurements, respectively. Raman spectroscopy and transmission electron microscopy (TEM) were used to compare the structure of FLG before and after incubation. All of the test fungi decreased pH in growth media and released H2O2 and laccase/peroxidase, but only basidiomycetes released LiP. Independent of growth media composition all fungi were found to be capable to oxidize FLG to a graphene oxide-like material, including M. esculenta, which released only laccase/peroxidase, i.e. the most common enzymes among primary decomposers. These findings suggest that FLG involuntarily released into terrestrial environments would likely be oxidized by soil microflora.


Assuntos
Grafite , Madeira , Ascomicetos , Biodegradação Ambiental , Coriolaceae , Fungos/metabolismo , Peróxido de Hidrogênio , Lacase/metabolismo , Lignina/metabolismo , Oxirredução , Peroxidases/metabolismo
13.
Appl Microbiol Biotechnol ; 105(11): 4453-4466, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34043082

RESUMO

Deamination of L-glutamine to glutamic acid with the concomitant release of ammonia by the activity of L-glutaminase (L-glutamine amidohydrolase EC 3.5.1.2) is a unique reaction that also finds potential applications in different sectors ranging from therapeutics to food industry. Owing to its cost-effectiveness, rapidity, and compatibility with downstream processes, microbial production of L-glutaminase is preferred over the production by other sources. Marine microorganisms including bacteria, yeasts, and moulds have manifested remarkable capacity to produce L-glutaminase and, therefore, are considered as prospective candidates for large-scale production of this enzyme. The main focus of this article is to provide an overview of L-glutaminase producing marine microorganisms, to discuss strategies used for the lab- and large-scale production of these enzyme and to review the application of L-glutaminase from marine sources so that the future prospects can be understood. KEY POINTS: • L-glutaminase has potential applications in different sectors ranging from therapeutics to food industry • Marine microorganisms are considered as prospective candidates for large-scale production of L-glutaminase • Marine microbial L-glutaminase have great potential in therapeutics and in the food industry.


Assuntos
Glutaminase , Preparações Farmacêuticas , Indústria Alimentícia , Fungos , Glutamina , Estudos Prospectivos
14.
Plant Physiol Biochem ; 165: 200-206, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34052681

RESUMO

Silicon (Si) acts as a beneficial element for plant growth and provides protection against abiotic and biotic stresses. Despite numerous reports on the beneficial role of Si in enhancing plant resistance to fungal pathogens, the underlying mechanisms remain largely unclear. Silicon shows antifungal activity; however, Si-induced improved disease resistance is partly manifested by the formation of Si polymerized mechanical obstruction under the cuticle and in cell walls, which prevents fungal ingress. Moreover, rapid production of defense compounds through secondary metabolic pathways is thought to be a key mechanism of Si-induced chemical defense against fungal pathogens beyond the physical barrier. Besides, improved mineral nutrition assures the healthy status of Si-supplied plants and a healthy plant exhibits better photosynthetic potential, antioxidant capacity and disease resistance. Multiple plant hormones and their crosstalk mediate the Si-induced basal as well as induced resistance; nonetheless, how root uptake of Si systemically modulates resistance to foliar diseases in low Si accumulating plants, needs in-depth investigation. Recent studies also indicate that Si influences effector-triggered immunity by affecting host recognition and/or limiting receptor-effector interactions. Here we review the role of Si in plant response to fungal pathogens. We also discuss and propose potential mechanisms of Si-induced enhanced disease resistance in plants. Finally, we identify some limitations of research approaches in addressing the beneficial roles of Si in biotic stress management.


Assuntos
Resistência à Doença , Silício , Fungos , Reguladores de Crescimento de Plantas , Plantas , Silício/farmacologia
15.
Appl Microbiol Biotechnol ; 105(10): 4017-4031, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33950280

RESUMO

The pentose phosphate pathway (PPP) is one of the most targeted pathways in metabolic engineering. This pathway is the primary source of NADPH, and it contributes in fungi to the production of many compounds of interest such as polyols, biofuels, carotenoids, or antibiotics. However, the regulatory mechanisms of the PPP are still not fully known. This review provides an insight into the current comprehension of the PPP in fungi and the limitations of this current understanding. It highlights how this knowledge contributes to targeted engineering of the PPP and thus to better performance of industrially used fungal strains. KEY POINTS: • Type of carbon and nitrogen source as well as oxidative stress influence the PPP. • A complex network of transcription factors regulates the PPP. • Improved understanding of the PPP will allow to increase yields of bioprocesses.


Assuntos
Fungos , Via de Pentose Fosfato , Biocombustíveis , Fungos/genética , Fungos/metabolismo , Engenharia Metabólica , NADP/metabolismo
16.
Appl Microbiol Biotechnol ; 105(10): 4111-4126, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33997930

RESUMO

Aryl-alcohol oxidases (AAOs) are FAD-containing enzymes that oxidize a broad range of aromatic as well as aliphatic allylic alcohols to aldehydes. Their broad substrate spectrum accompanied by the only need for molecular oxygen as cosubstrate and production of hydrogen peroxide as sole by-product makes these enzymes very promising biocatalysts. AAOs were used in the synthesis of flavors, fragrances, and other high-value-added compounds and building blocks as well as in dye decolorization and pulp biobleaching. Furthermore, AAOs offer a huge potential as efficient suppliers of hydrogen peroxide for peroxidase- and peroxygenase-catalyzed reactions. A prerequisite for application as biocatalysts at larger scale is the production of AAOs in sufficient amounts. Heterologous expression of these predominantly fungal enzymes is, however, quite challenging. This review summarizes different approaches aiming at enhancing heterologous expression of AAOs and gives an update on substrates accepted by these promising enzymes as well as potential fields of their application. KEY POINTS: • Aryl-alcohol oxidases (AAOs) supply ligninolytic peroxidases with H2O2. • AAOs accept a broad spectrum of aromatic and aliphatic allylic alcohols. • AAOs are potential biocatalysts for the production of high-value-added bio-based chemicals.


Assuntos
Oxirredutases do Álcool , Peróxido de Hidrogênio , Oxirredutases do Álcool/genética , Álcoois , Fungos/genética , Lignina , Peroxidase , Peroxidases
17.
J Nanosci Nanotechnol ; 21(11): 5383-5398, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33980348

RESUMO

Antimicrobial resistance has become a severe problem for health systems worldwide, and counteractions are challenging because of the lack of interest of pharmaceutical companies in generating new and effective antimicrobial drugs. Selenium nanoparticles have attracted considerable interest in treating bacteria, fungi, parasites, and viruses of clinical importance due to their high therapeutic efficacy and almost zero generation of adverse effects. Some studies have revealed that the antimicrobial activity of these nanoparticles is due to the generation of reactive oxygen species, but more studies are needed to clarify their antimicrobial mechanisms. Other studies show that their antimicrobial activity is increased when the surface of the nanoparticles is functionalized with some biomolecules or when their surface carries a specific drug. This review addresses the existing background on the antimicrobial potential offered by selenium nanoparticles against viruses, bacteria, fungi, and parasites of clinical importance.


Assuntos
Anti-Infecciosos , Nanopartículas , Preparações Farmacêuticas , Selênio , Anti-Infecciosos/farmacologia , Fungos
18.
New Phytol ; 231(2): 777-790, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34013982

RESUMO

Fungi are known to exert a significant influence over soil organic matter (SOM) turnover, however understanding of the effects of fungal community structure on SOM dynamics and its consequences for ecosystem fertility is fragmentary. Here we studied soil fungal guilds and SOM decomposition processes along a fertility gradient in a temperate mountain beech forest. High-throughput sequencing was used to investigate fungal communities. Carbon and nitrogen stocks, enzymatic activity and microbial respiration were measured. While ectomycorrhizal fungal abundance was not related to fertility, saprotrophic ascomycetes showed higher relative abundances under more fertile conditions. The activity of oxidising enzymes and respiration rates in mineral soil were related positively to fertility and saprotrophic fungi. In addition, organic layer carbon and nitrogen stocks were lower on the more fertile plots, although tree biomass and litter input were higher. Together, the results indicated a faster SOM turnover at the fertile end of the gradient. We suggest that there is a positive feedback mechanism between SOM turnover and fertility that is mediated by soil fungi to a significant extent. By underlining the importance of fungi for soil fertility and plant growth, these findings furthermore emphasise the dependency of carbon cycling on fungal communities below ground.


Assuntos
Micobioma , Solo , Carbono , Ecossistema , Florestas , Fungos , Microbiologia do Solo
19.
J Hazard Mater ; 412: 125215, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33951860

RESUMO

Ionic liquids (ILs), being related to the design of new environmentally friendly solvents, are widely considered for applications within the "green chemistry" concept. Due to their unique properties and wide diversity, ILs allow tailoring new separation procedures and producing new materials for advanced applications. However, despite the promising technical performance, environmental concerns highlighted in recent studies focused on the toxicity and biodegradability of ILs and their metabolites have revealed that ILs safety labels are not as benign as previously claimed. This review refers to the fundamentals about the properties and applications of ILs also in the context of their potential environmental effect. Toxicological issues and harmful effects related to the use of ILs are discussed, including the evaluation of their biodegradability and ecological impact on diverse organisms and ecosystems, also with respect to bacteria, fungi, and cell cultures. In addition, this review covers the tools used to assess the toxicity of ILs, including the predictive computational models and the results of studies involving cell membrane models and molecular simulations. Summing up the knowledge available so far, there are still no reliable criteria for unequivocal attribution of toxicity and environmental impact credentials for ILs, which is a challenging research task.


Assuntos
Líquidos Iônicos , Ecossistema , Fungos , Líquidos Iônicos/toxicidade , Solventes
20.
Ecotoxicology ; 30(5): 986-995, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33991262

RESUMO

Coral reef ecosystems usually distribute in oligotrophic tropical and subtropical marine environments, but they possess great biodiversity and high productivity. It may attribute to its efficient internal nutrient cycle system. However, the knowledge of functional microbial community structure is still limited. In this study, both functional gene array (Geochip 5.0) and nifH Illumina sequencing were used to profile the overall functional genes and diazotrophic communities associated with coral Porites pukoensis. More than 7500 microbial functional genes were detected from archaea, bacteria, and fungi. Most of these genes are related to the transformation of carbon, nitrogen, sulfur, and phosphorus, providing evidence that microbes in the coral holobiont play important roles in the biogeochemical cycle of coral reef ecosystems. Our results indicated a high diversity of diazotrophs associated with corals. The dominant diazotrophic groups were related to phyla Alphaproteobacteria, Deltaproteobacteria, Cyanobacteria, and Gammaproteobacteria. And the dominant diazotrophic communities were divided into four clusters. They were affiliated with nifH sequences from genera Zymomonas, Halorhodospira, Leptolyngbya, Trichormus, and Desulfovibrio, indicating these groups may play a more important role in the nitrogen-fixing process in the coral holobiont. This study revealed functional gene diversity and suggested the roles they played in the biogeochemical cycling of the coral holobiont.


Assuntos
Antozoários , Animais , Antozoários/genética , Archaea , Biodiversidade , Recifes de Corais , Fungos
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