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1.
Nat Plants ; 9(11): 1810-1817, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37845335

RESUMO

Large-scale, abrupt ecosystem change in direct response to climate extremes is a critical but poorly documented phenomenon1. Yet, recent increases in climate-induced tree mortality raise concern that some forest ecosystems are on the brink of collapse across wide environmental gradients2,3. Here we assessed climatic and productivity trends across the world's five Mediterranean forest ecosystems from 2000 to 2021 and detected a large-scale, abrupt forest browning and productivity decline in Chile (>90% of the forest in <100 days), responding to a sustained, acute drought. The extreme dry and warm conditions in Chile, unprecedented in the recent history of all Mediterranean-type ecosystems, are akin to those projected to arise in the second half of the century4. Long-term recovery of this forest is uncertain given an ongoing decline in regional water balance. This dramatic plummet of forest productivity may be a spyglass to the future for other Mediterranean ecosystems.


Assuntos
Mudança Climática , Ecossistema , Florestas , Árvores/fisiologia , Secas
2.
J Environ Manage ; 342: 118087, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37196613

RESUMO

A solution approach is proposed to optimize the selection of landscape cells for inclusion in firebreaks. It involves linking spatially explicit information on a landscape's ecological values, historical ignition patterns and fire spread behavior. A firebreak placement optimization model is formulated that captures the tradeoff between the direct loss of biodiversity due to the elimination of vegetation in areas designated for placement of firebreaks and the protection provided by the firebreaks from losses due to future forest fires. The optimal solution generated by the model reduced expected losses from wildfires on a biodiversity combined index due to wildfires by 30% relative to a landscape without any treatment. It also reduced expected losses by 16% compared to a randomly chosen solution. These results suggest that biodiversity loss resulting from the removal of vegetation in areas where firebreaks are placed can be offset by the reduction in biodiversity loss due to the firebreaks' protective function.


Assuntos
Incêndios , Incêndios Florestais , Biodiversidade , Florestas
3.
Nat Commun ; 14(1): 466, 2023 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709343

RESUMO

The RNA binding protein TDP-43 forms cytoplasmic inclusions via its C-terminal prion-like domain in several neurodegenerative diseases. Aberrant TDP-43 aggregation arises upon phase de-mixing and transitions from liquid to solid states, following still unknown structural conversions which are primed by oxidative stress and chaperone inhibition. Despite the well-established protective roles for molecular chaperones against protein aggregation pathologies, knowledge on the determinants of chaperone recognition in disease-related prions is scarce. Here we show that chaperones and co-chaperones primarily recognize the structured elements in TDP-43´s prion-like domain. Significantly, while HSP70 and HSP90 chaperones promote TDP-43 phase separation, co-chaperones from the three classes of the large human HSP40 family (namely DNAJA2, DNAJB1, DNAJB4 and DNAJC7) show strikingly different effects on TDP-43 de-mixing. Dismantling of the second helical element in TDP-43 prion-like domain by methionine sulfoxidation impacts phase separation and amyloid formation, abrogates chaperone recognition and alters phosphorylation by casein kinase-1δ. Our results show that metamorphism in the post-translationally modified TDP-43 prion-like domain encodes determinants that command mechanisms with major relevance in disease.


Assuntos
Proteínas de Ligação a DNA , Príons , Humanos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Choque Térmico , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP70 , Chaperonas Moleculares/metabolismo , Príons/metabolismo , Agregados Proteicos
4.
J Fungi (Basel) ; 8(9)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36135678

RESUMO

Cultivated mushrooms are well-known nutrient inputs for an equilibrated diet. Some species are broadly appreciated due to their medicinal properties. Lately, a number of novel foods and nutraceuticals based on dehydrated and freeze-dried powder obtained from cultivated mushrooms has been reaching the market. The food industry requires fast and reliable tools to prevent fraud. In this, work we have cultivated Agaricus bisporus sp. bisporus (AB) (white button mushroom), Agaricus bisporus sp. brunnescens (ABP) (portobello), Lentinula edodes (LE) (shiitake) and Grifola frondosa (GF) (maitake) using tailor-made substrates for the different species and standardized cropping conditions, which were individually freeze-dried to obtain the samples under evaluation. The aim of this article was to validate the use of two different methodologies, namely, electronic nose and sensory panel, to discriminate the olfactory profile of nutritional products based on freeze-dried mushrooms from the different cultivated species. Additionally, GC-MS was used to detect and quantify the most abundant volatile organic compounds (VOCs) in the samples. The multivariate analysis performed proved the utility of electronic nose as an analytical tool, which was similar to the classical sensory panel but faster in distinguishing among the different species, with one limitation it being unable to differentiate between the same species. GC-MS analysis showed the chemical volatile formulation of the samples, also showing significant differences between different samples but high similarities between varieties of the same cultivated species. The techniques employed can be used to prevent fraud and have the potential to evaluate further medicinal mushroom species and build solid and trustful connections between these novel food products and potential consumers.

5.
BMC Genomics ; 23(1): 442, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35701764

RESUMO

The cultivation of edible mushroom is an emerging sector with a potential yet to be discovered. Unlike plants, it is a less developed agriculture where many studies are lacking to optimize the cultivation. In this work we have employed high-throughput techniques by next generation sequencing to screen the microbial structure of casing soil employed in mushroom cultivation (Agaricus bisporus) while sequencing V3-V4 of the 16S rRNA gene for bacteria and the ITS2 region of rRNA for. In addition, the microbiota dynamics and evolution (bacterial and fungal communities) in peat-based casing along the process of incubation of A. bisporus have been studied, while comparing the effect of fungicide treatment (chlorothalonil and metrafenone). Statistically significant changes in populations of bacteria and fungi were observed. Microbial composition differed significantly based on incubation day, changing radically from the original communities in the raw material to a specific microbial composition driven by the A. bisporus mycelium growth. Chlorothalonil treatment seems to delay casing colonization by A. bisporus. Proteobacteria and Bacteroidota appeared as the most dominant bacterial phyla. We observed a great change in the structure of the bacteria populations between day 0 and the following days. Fungi populations changed more gradually, with A. bisporus displacing the rest of the species as the cultivation cycle progresses. A better understanding of the microbial communities in the casing will hopefully allow us to increase the biological efficiency of the crop.


Assuntos
Agaricus , Fungicidas Industriais , Agaricus/genética , Bactérias/genética , Fungos/genética , Fungicidas Industriais/farmacologia , RNA Ribossômico 16S/genética , Solo
6.
J Environ Manage ; 297: 113428, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34375228

RESUMO

The strong link between climate change and increased wildfire risk suggests a paradigm change on how humans must co-exist with fire and the environment. Different studies have demonstrated that human-induced fire ignitions can account for more than 90 % of forest fires, so human co-existence with wildfires requires informed decision making via preventive policies in order to minimize risk and adapt to new conditions. In this paper, we address the multidimensional effects of three groups of drivers (human activity, geographic and topographic, and land cover) that can be managed to assist in territorial planning under fire risk. We found critical factors of strong interactions with the potential to increase the likelihood of starting a fire. Our solution approach included the application of a Machine Learning method called Random Undersampling and Boosting (RUSBoost) to assess risk (fire occurrence probability), which was subsequently accompanied by a sensitivity analysis that revealed interactions of various levels of risk. The prediction performance of the proposed model was assessed using several statistical measures such as the Receiver Operating Characteristic curve (ROC) and the Area Under the Curve (AUC). The results confirmed the high accuracy of our model, with an AUC of 0.967 and an overall accuracy over test data of 93.01 % after applying a Bayesian approach for hyper-parameter optimization. The study area to test our solution approach comprised the entire geographical territory of central Chile.


Assuntos
Incêndios Florestais , Teorema de Bayes , Mudança Climática , Atividades Humanas , Humanos , Probabilidade
8.
Microorganisms ; 9(3)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809140

RESUMO

Mycoparasites cause heavy losses in commercial mushroom farms worldwide. The negative impact of fungal diseases such as dry bubble (Lecanicillium fungicola), cobweb (Cladobotryum spp.), wet bubble (Mycogone perniciosa), and green mold (Trichoderma spp.) constrains yield and harvest quality while reducing the cropping surface or damaging basidiomes. Currently, in order to fight fungal diseases, preventive measurements consist of applying intensive cleaning during cropping and by the end of the crop cycle, together with the application of selective active substances with proved fungicidal action. Notwithstanding the foregoing, the redundant application of the same fungicides has been conducted to the occurrence of resistant strains, hence, reviewing reported evidence of resistance occurrence and introducing unconventional treatments is worthy to pave the way towards the design of integrated disease management (IDM) programs. This work reviews aspects concerning chemical control, reduced sensitivity to fungicides, and additional control methods, including genomic resources for data mining, to cope with mycoparasites in the mushroom industry.

9.
Molecules ; 26(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374385

RESUMO

This study aimed to obtain a third-generation snack from native rice starch (NS), rice starch modified by extrusion (MS), nopal flour (NF) and xanthan gum (XG). These raw materials were characterized by proximal analysis, pH, particle size distribution, water absorption index (WAI) and water solubility index (WSI), degree of substitution (DS), differential scanning calorimetry (DSC), rheology, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The analysis of the response variables in the nine formulations of the snack: expansion index (EI), apparent density (AD), hardness (H), luminosity (L*) and tendency to green-red (a*), was performed through a composite central design (CCD), the selected formulations were characterized by SEM. Results showed an increase in WAI, 4.69 ± 0.04, and WSI, 12.61 ± 0.10, for MS, higher than NS values due to chemical modification. According to the color analysis the NF obtained a value of 60.73 ± 0.008 in L* and -6.51 ± 0.004 in a* with green tendency. The DS value obtained was 0.09 ± 0.005, being within the FDA's permissible range for food use. By FTIR analysis, the acetyl group was corroborated. Finally, employing microwave cooking, snacks made from NS with concentrations of NF (5%) and XG (0%) obtained the highest EI value, 4.47, as well the low Dap and D value (0.37 g/cm3, 2.25 N, respectively), corroborated by SEM analysis.


Assuntos
Farinha/análise , Opuntia/química , Oryza/química , Lanches , Amido/química , Algoritmos , Fenômenos Químicos , Análise de Alimentos , Modelos Teóricos , Solubilidade , Análise Espectral , Amido/ultraestrutura
10.
Microb Biotechnol ; 13(6): 1933-1947, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32716608

RESUMO

Microorganisms strongly influence and are required to generate the selective substrate that provides nutrients and support for fungal growth, and ultimately to induce mushroom fructification under controlled environmental conditions. In this work, the fungal and bacterial microbiota living in the different substrates employed in a commercial crop (compost phase I, II and III, flush 1 and 2, and casing material on day 1, 6 and 8 after compost casing and during flush 1 and 2) have been characterized along the different stages of cultivation by metataxonomic analysis (16S rRNA and ITS2), analysis of phospholipid fatty acid content (PLFAs) and RT-qPCR. Additionally, laccase activity and the content of lignin and complex carbohydrates in compost and casing have been quantified. The bacterial diversity in compost and casing increased throughout the crop cycle boosted by the connection of both substrates. As reflected by the PLFAs, the total living bacterial biomass appears to be negatively correlated with the mycelium of the crop. Agaricus bisporus was the dominant fungal species in colonized substrates, displacing the pre-eminent Ascomycota, accompanied by a sustained increase in laccase activity, which is considered to be a major product of protein synthesis during the mycelial growth of champignon. From phase II onwards, the metabolic machinery of the fungal crop degrades lignin and carbohydrates in compost, while these components are hardly degraded in casing, which reflects the minor role of the casing for nourishing the crop. The techniques employed in this study provide a holistic and detailed characterization of the changing microbial composition in commercial champignon substrates. The knowledge generated will contribute to improve compost formulations (selection of base materials) and accelerate compost production, for instance, through biotechnological interventions in the form of tailored biostimulants and to design environmentally sustainable bio-based casing materials.


Assuntos
Agaricus , Compostagem , Microbiota , RNA Ribossômico 16S/genética , Solo
11.
Environ Microbiol ; 22(3): 858-872, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31361932

RESUMO

Mushroom cropping consists of the development and fructification of different fungal species in soil or selective substrates that provide nutrients and support for the crop. The microorganisms present in these environments strongly influence, and in some cases are required for the growth and fructification of cultivated mushrooms. Some fungi such as truffles and morels form ectomycorrhizal associations with host plants. For these fungi, helper bacteria play an important role in the establishment of plant-fungal symbioses. Selective processes acting on the microbiota present in substrates and soils determine the composition of the microbiota inhabiting the fruit bodies or interacting with fungal hyphae, and both configure the mushroom holobiont, understood as the fungus plus associated microorganisms. Here, we review current knowledge regarding the cross-talk between bacteria and fungi during mushroom cultivation. We highlight the potential use of bioinoculants as agronomical amendments to increase mushroom productivity through growth promotion or as biocontrol agents to control pests and diseases.


Assuntos
Agaricales/fisiologia , Fenômenos Fisiológicos Bacterianos , Microbiologia do Solo , Micorrizas/fisiologia , Plantas/microbiologia
12.
Indian J Microbiol ; 59(3): 328-335, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31388210

RESUMO

Among the cultivated mushroom, the genus Pleurotus is the second largest produced worldwide and the most produced in Brazil. The application of agricultural by-products (wastes) as substrate supplement is an effective approach to generate quality food while promoting a circular economy in agriculture. The manuscript evaluates the three key aspects of this practice: (1) the response of different mushroom strains to supplementation, (2) the use of agricultural by-products with different N content, and (3) the efficacy of certain preliminary treatments applied to the supplements. To this end, production and nutritional quality of the mushroom were tested along the crop cycle. Compared to the control substrate, the yield increased by 11, 26, 30 and 42% in the first flush and by 86 and 31% in the second flush. Supplementation resulted in an increment of the fiber and protein content of mushroom and a decline of carbohydrate and lipid content of mushroom.

13.
Microbiology (Reading) ; 165(6): 611-624, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30994437

RESUMO

The casing material required in mushroom cultivation presents a very rich ecological niche, which is inhabited by a diverse population of bacteria and fungi. In this work three different casing materials, blonde peat, black peat and a 50 : 50 mixture of both, were compared for their capacity to show a natural suppressive response against dry bubble, Lecanicillium fungicola (Preuss) Zare and Gams, and wet bubble, Mycogone perniciosa (Magnus) Delacroix. The highest mushroom production was collected from crops cultivated using the mixed casing and black peat, which were not significantly different in yield. However, artificial infection with mycoparasites resulted in similar yield losses irrespective of the material used, indicating that the casing materials do not confer advantages in disease suppression. The composition of the microbiome of the 50 : 50 casing mixture along the crop cycle and the compost and basidiomes was evaluated through next-generation sequencing (NGS) of the V3-V4 region of the bacterial 16S rRNA gene and the fungal ITS2 region. Once colonized by Agaricus bisporus, the bacterial diversity of the casing microbiome increased and the fungal diversity drastically decreased. From then on, the composition of the casing microbiome remained relatively stable. Analysis of the composition of the bacterial microbiome in basidiomes indicated that it is highly influenced by the casing microbiota. Notably, L. fungicola was consistently detected in uninoculated control samples of compost and casing using NGS, even in asymptomatic crops. This suggests that the naturally established casing microbiota was able to help to suppress disease development when inoculum levels were low, but was not effective in suppressing high pressure from artificially introduced fungal inoculum. Determination of the composition of the casing microbiome paves the way for the development of synthetic casing communities that can be used to investigate the role of specific components of the casing microbiota in mushroom production and disease control.


Assuntos
Agaricus/crescimento & desenvolvimento , Microbiota/fisiologia , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Meios de Cultura/química , Hypocreales/crescimento & desenvolvimento , Hypocreales/isolamento & purificação , Interações Microbianas , RNA Ribossômico 16S/genética
14.
AMB Express ; 8(1): 146, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30229415

RESUMO

Mushroom supplementation is an agronomic process which consists of the application of nutritional amendments to the substrates employed for mushroom cultivation. Different nitrogen and carbohydrate rich supplements have been evaluated in crops with a substantial impact on mushroom yield and quality; however, there is still controversy regarding the nutritional requirements of mushrooms and the necessity for the development of new commercial additives. The addition of external nutrients increases the productivity of some low-yielding mushroom varieties, and therefore is a useful tool for the industry to introduce new commercially viable varieties. Spent mushroom compost is a waste material that could feasibly be recycled as a substrate to support a new commercially viable crop cycle when amended with supplements. On the other hand, a new line of research based on the use of mushroom growth promoting microorganisms is rising above the horizon to supplement the native microbiota, which appears to cover nutritional deficiencies. Several supplements employed for the cultivated mushrooms and their agronomic potential in terms of yield and quality are reviewed in this paper as a useful guide to evaluate the nutritional requirements of the crop and to design new formulas for commercial supplementation.

15.
J Sci Food Agric ; 96(11): 3838-45, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26692380

RESUMO

BACKGROUND: This work assesses the agronomic performance of defatted pistachio meal, after oil extraction, as a nutritional substrate supplement when growing the mushroom species Agaricus bisporus (Lange) Imbach and Pleurotus ostreatus (Jacq.) P. Kumm. Materials were applied at different doses at spawning. Along with non-supplemented substrates, commercial nutritional supplements were used as controls. Proximate analysis of mushrooms is also considered. RESULTS: For the cultivation of champignon, defatted pistachio meal has provided larger mushrooms (unitary weight and cap diameter) with firmer texture and greater content in dry weight and protein, without significant alterations in quantitative parameters. For Pleurotus ostreatus, the supplement led to significant yield increase, even providing up to 34.4% of increment compared to non-supplementation with meal, reaching a biological efficiency of 129.9 kg dt(-1) , when applied to the 15 g kg(-1) compost dose. Supplementation has also been conducted to increase dry weight, protein and fibre within carpophores and to decrease the energy value. Defatted pistachio meal has similar or better results compared to the commercial supplements used as reference. CONCLUSIONS: Compost supplementation with defatted pistachio meal in A. bisporus concerns mainly the quantitative parameters (size, texture, dry weight and protein). Based on the results obtained, this technique has greater potential of development for P. ostreatus commercial crops, basically due to expected increases in production, with a direct impact on benefits and crop profitability. © 2015 Society of Chemical Industry.


Assuntos
Agaricus/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Qualidade dos Alimentos , Resíduos Industriais/análise , Nozes/química , Pistacia/química , Pleurotus/crescimento & desenvolvimento , Agaricus/química , Agaricus/metabolismo , Agricultura/métodos , Produtos Agrícolas/química , Produtos Agrícolas/economia , Produtos Agrícolas/metabolismo , Gorduras na Dieta/análise , Fibras na Dieta/análise , Proteínas Alimentares/análise , Indústria de Processamento de Alimentos/economia , Proteínas Fúngicas/análise , Proteínas Fúngicas/biossíntese , Humanos , Resíduos Industriais/economia , Fenômenos Mecânicos , Micologia/métodos , Valor Nutritivo , Pleurotus/química , Pleurotus/metabolismo , Espanha , Regulação para Cima
16.
Pediatr Infect Dis J ; 32(10): 1066-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23722530

RESUMO

AIM: To determine whether the treatment with oseltamivir improves the outcome of children with confirmed influenza infection and no other underlying disease. METHODS: Multicentric, retrospective study performed in 10 hospitals of Madrid between September 2010 and June 2012. All children admitted to the hospitals with confirmed influenza infections were eligible. Children with risk factors for serious disease and nosocomial influenza infections were excluded. Asthma was not considered an exclusion factor. The study compared patients treated and untreated with oseltamivir. Fever duration, oxygen support, antibiotics administration, length of hospital stay, intensive care admission and bacterial complications were analyzed. To compare variables, χ(2) test, Fisher exact test, ANOVA or Mann-Whitney U test were used. RESULTS: Two hundred eighty-seven children were included and 93 of them were treated with oseltamivir (32%). There were no significant differences between treated and untreated patients in days of fever after admission (1.7 ± 2; 2.1 ± 2.9, P > 0.05), length of stay (5.2 ± 3.6; 5.5 ± 3.4, P > 0.05), days of hypoxia (1.6 ± 2.3; 2.1 ± 2.9, P > 0.05), diagnosis of bacterial pneumonia (10%; 17%, P > 0.05), intensive care admission (6.5%; 1.5%,P > 0.05) or antibiotic prescription (44%; 51%, P > 0.05). There were no differences when the population was stratified by age (below or over 1 year) or by the presence or absence of asthma. CONCLUSIONS: There were no proven benefits of treatment with oseltamivir in hospitalized pediatric patients without the underlying diseases or risk factors for developing a serious illness, including those with asthma.


Assuntos
Antivirais/uso terapêutico , Influenza Humana/tratamento farmacológico , Oseltamivir/uso terapêutico , Análise de Variância , Distribuição de Qui-Quadrado , Pré-Escolar , Feminino , Febre/virologia , Hospitalização , Humanos , Lactente , Tempo de Internação , Masculino , Estudos Retrospectivos
17.
J Agric Food Chem ; 60(13): 3331-40, 2012 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-22394577

RESUMO

Iron chlorosis is a very common nutritional disorder in plants that can be treated using iron fertilizers. Synthetic chelates have been used to correct this problem, but nowadays environmental concerns have enforced the search for new, more environmentally friendly ligands, such as lignosulfonates. In this paper, Fe coordination environment and speciation in lignosulfonate (LS) complexes prepared under different experimental conditions were studied by (57)Fe Mössbauer spectroscopy in relation to the Fe-complexing capacities, chemical characteristics of the different products, and efficiency to provide iron in agronomic conditions. It has been observed that the complex formation between iron and lignosulfonates involves different coordination sites. When Fe(2+) is used to prepare the iron-LS product, complexes form weak adducts and are sensitive to oxidation, especially at neutral or alkaline pH. However, when Fe(3+) is used to form the complexes, both Fe(2+) and Fe(3+) are found. Reductive sugars, normally present in lignosulfonates, favor a relatively high content of Fe(2+) even in those complexes prepared using Fe(3+). The formation of amorphous ferrihydrite is also possible. With respect to the agronomical relevance of the Fe(2+)/Fe(3+) speciation provided by the Mössbauer spectra, it seems that the strong Fe(3+)-LS complexes are preferred when they are applied to the leaf, whereas root uptake in hydroponics could be more related with the presence of weak bonding sites.


Assuntos
Fertilizantes/análise , Ferro/química , Lignina/análogos & derivados , Concentração de Íons de Hidrogênio , Ligantes , Lignina/química , Espectroscopia de Mossbauer
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