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1.
Int J Nanomedicine ; 16: 2419-2441, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33814908

RESUMEN

Lignin is an abundant renewable natural biopolymer. Moreover, a significant development in lignin pretreatment and processing technologies has opened a new window to explore lignin and lignin-based bionanomaterials. In the last decade, lignin has been widely explored in different applications such as drug and gene delivery, tissue engineering, food science, water purification, biofuels, environmental, pharmaceuticals, nutraceutical, catalysis, and other interesting low-value-added energy applications. The complex nature and antioxidant, antimicrobial, and biocompatibility of lignin attracted its use in various biomedical applications because of ease of functionalization, availability of diverse functional sites, tunable physicochemical and mechanical properties. In addition to it, its diverse properties such as reactivity towards oxygen radical, metal chelation, renewable nature, biodegradability, favorable interaction with cells, nature to mimic the extracellular environment, and ease of nanoparticles preparation make it a very interesting material for biomedical use. Tremendous progress has been made in drug delivery and tissue engineering in recent years. However, still, it remains challenging to identify an ideal and compatible nanomaterial for biomedical applications. In this review, recent progress of lignin towards biomedical applications especially in drug delivery and in tissue engineering along with challenges, future possibilities have been comprehensively reviewed.


Asunto(s)
Sistemas de Liberación de Medicamentos , Técnicas de Transferencia de Gen , Lignina/química , Ingeniería de Tejidos , Animales , Biomasa , Humanos , Nanopartículas/química , Nanopartículas/ultraestructura
2.
Nat Commun ; 12(1): 1512, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33686076

RESUMEN

Bioenergy with carbon capture and storage (BECCS) is considered an important negative emissions (NEs) technology, but might involve substantial irrigation on biomass plantations. Potential water stress resulting from the additional withdrawals warrants evaluation against the avoided climate change impact. Here we quantitatively assess potential side effects of BECCS with respect to water stress by disentangling the associated drivers (irrigated biomass plantations, climate, land use patterns) using comprehensive global model simulations. By considering a widespread use of irrigated biomass plantations, global warming by the end of the 21st century could be limited to 1.5 °C compared to a climate change scenario with 3 °C. However, our results suggest that both the global area and population living under severe water stress in the BECCS scenario would double compared to today and even exceed the impact of climate change. Such side effects of achieving substantial NEs would come as an extra pressure in an already water-stressed world and could only be avoided if sustainable water management were implemented globally.


Asunto(s)
Biomasa , Cambio Climático , Deshidratación , Carbono , Simulación por Computador , Calentamiento Global , Humanos , Plantas , Agua
3.
Molecules ; 26(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668952

RESUMEN

In this study, we investigated the influence of epoxy resin treatment on the mechanical and tribological properties of hemp fiber (HF)-reinforced plant-derived polyamide 1010 (PA1010) biomass composites. HFs were surface-treated using four types of surface treatment methods: (a) alkaline treatment using sodium chlorite (NaClO2) solution, (b) surface treatment using epoxy resin (EP) solution after NaClO2 alkaline treatment, (c) surface treatment using an ureidosilane coupling agent after NaClO2 alkaline treatment (NaClO2 + A-1160), and (d) surface treatment using epoxy resin solution after the (c) surface treatment (NaClO2 + A-1160 + EP). The HF/PA1010 biomass composites were extruded using a twin-screw extruder and injection-molded. Their mechanical properties, such as tensile, bending, and dynamic mechanical properties, and tribological properties were evaluated by the ring-on-plate-type sliding wear test. The strength, modulus, specific wear rate, and limiting pv value of HF/PA1010 biomass composites improved with surface treatment using epoxy resin (NaClO2 + A-1160 + EP). In particular, the bending modulus of NaClO2 + A-1160 + EP improved by 48% more than that of NaClO2, and the specific wear rate of NaClO2 + A-1160 + EP was one-third that of NaClO2. This may be attributed to the change in the internal microstructure of the composites, such as the interfacial interaction between HF and PA1010 and fiber dispersion. As a result, the mode of friction and wear mechanism of these biomass composites also changed.


Asunto(s)
Resinas Compuestas/química , Resinas Epoxi/química , Nylons/química , Biomasa , Ensayo de Materiales , Tamaño de la Partícula , Estrés Mecánico , Propiedades de Superficie
4.
Bioresour Technol ; 329: 124870, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33652189

RESUMEN

The aim of this review is to provide insights into the upstream processing of microalgae, and to highlight the advantages of each step. This review discusses the most important steps of the upstream processing in microalgae research such as cultivation modes, photobioreactors design, preparation of culture medium, control of environmental factors, supply of microalgae seeds and monitoring of microalgal growth. An extensive list of bioreactors and their working volumes used, elemental composition of some well-known formulated cultivation media, different types of wastewater used for microalgal cultivation and environmental variables studied in microalgae research has been compiled in this review from the vast literature. This review also highlights existing challenges and knowledge gaps in upstream processing of microalgae and future research needs are suggested.


Asunto(s)
Microalgas , Biomasa , Medios de Cultivo , Fotobiorreactores , Aguas Residuales
5.
Waste Manag ; 125: 10-26, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33667979

RESUMEN

Anaerobic digestion is one of the main waste-to-energy technologies in reducing the volume of biodegradable waste into energy-rich biogas. Recent studies have revealed that kitchen wastes as a feedstock possess great potential in energy production and anaerobic digestion proved to be a promising technology among different kitchen waste management techniques such as incineration, pyrolysis, gasification, landfills, composting, etc. To anaerobically treat feedstock, an airtight enclosed container commonly known as biodigester will be employed. To suffice the energy requirement for cooking in the rural areas and recently even in the urban areas, a small-scale biogas unit commonly referred to as portable type biodigester is blooming as an attractive alternative for the production of biogas domestically. Hence, this review emphasizes on anaerobic digestion of kitchen wastes and the design of portable type biodigester. The present review provides an overview of different kitchen waste management techniques. The paper also discusses the different types of biomass feedstock and provides a generalized procedure for the design of a portable biogas unit. This study confirms that the systematic design of biogas units and proper feeding of kitchen waste offers an advantage of effective utilization of wastes in the production of decentralized energy.


Asunto(s)
Biocombustibles , Instalaciones de Eliminación de Residuos , Anaerobiosis , Biomasa , Reactores Biológicos , Incineración
6.
Waste Manag ; 125: 204-214, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33711734

RESUMEN

Steam co-gasification of banana peel with other biomass, i.e., Japanese cedar wood, rice husk and their mixture, was carried out for the hydrogen-rich gas production in a fixed-bed reactor. For the co-gasification process, the banana peels were physically mixed with rice husk, Japanese cedarwood and their mixture respectively by different mixing weight ratios. The effects of reaction temperature and the addition amount of banana peel on the gas production yield were investigated by comparing the experimental data with the calculated ones based on the individual biomass gasification at the same condition. It was found that the banana peel with a high content of alkali and alkaline earth metal (AAEM) species exhibited not only high gasification reactivity but also a significant enhancing catalytic effect on the co-gasification process at the low temperature, especially with the biomass containing no silica species. The high content of silica species in the rice husk had a negative effect on the gasification reactivity of banana peel during the co-gasification since it could hinder the release of AAEM from the biomass and/or lead to the possible formation of inactive alkaline silicates. However, the combination of these three samples with the suitable weight ratio could improve the gasification performance at the low temperature due to the synergetic effect provided by high contents of potassium and calcium from banana peel and cedarwood respectively. Moreover, the addition of calcined seashells as the CaO source could further improve the gas production yield, especially the hydrogen gas yield at a relatively low gasification temperature of 750 ℃.


Asunto(s)
Musa , Vapor , Biomasa , Hidrógeno , Madera
7.
Ecotoxicol Environ Saf ; 214: 112072, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33691243

RESUMEN

The Green Revolution faced a great cost to meet ever-increasing demands for food, where indiscriminate use of agrochemicals resulted in non-friendly habitats. Therefore, the development of a sustainable approach to better crop production of onion seeds (Allium cepa L.) is very crucial. It is time to use organic waste as a replacement for agrochemicals by using arbuscular mycorrhizal fungi (AMF) and Trichoderma. Fish waste as representative of food waste acts as a leading cause of contamination of the environment. The interaction of AMF and Trichoderma viride on biomass, total soluble protein, mycorrhizal colonization, amino acids, phosphatases and phosphorus and nitrogen contents of onion plants grown in fish waste amended soil was studied. Fish waste has caused a slight increase in onions biomass, total free amino acids, and soluble protein content while with AMF and T. viride dual inoculation more increments were recorded; such increases were related to an increase in mycorrhizal colonization. T. viride application significantly increased the mycorrhizal colonization levels, but these were significantly reduced with waste addition. Analysis of amino acids in plants showed that their concentrations had changed as a result of waste addition combined with AMF and/or T. viride. The effectiveness of fish waste combined with low cost and health/environmental safety leads to a prediction that the introduction of fish waste coupled with fungi will become a more popular feature of agriculture in the future.


Asunto(s)
Micorrizas/fisiología , Cebollas/fisiología , Trichoderma/fisiología , Agricultura , Aminoácidos/metabolismo , Biomasa , Alimentos , Hongos/metabolismo , Hypocreales , Micorrizas/metabolismo , Nitrógeno/metabolismo , Cebollas/química , Monoéster Fosfórico Hidrolasas/metabolismo , Fósforo/metabolismo , Eliminación de Residuos , Suelo , Trichoderma/metabolismo
8.
Sheng Wu Gong Cheng Xue Bao ; 37(3): 1058-1069, 2021 Mar 25.
Artículo en Chino | MEDLINE | ID: mdl-33783168

RESUMEN

The efficient production of lignocellulolytic enzyme systems is an important support for large-scale biorefinery of plant biomass. On-site production of lignocellulolytic enzymes could increase the economic benefits of the process by lowering the cost of enzyme usage. Penicillium species are commonly found lignocellulose-degrading fungi in nature, and have been used for industrial production of cellulase preparations due to their abilities to secrete complete and well-balanced lignocellulolytic enzyme systems. Here, we introduce the reported Penicillium species for cellulase production, summarize the characteristics of their enzymes, and describe the strategies of strain engineering for improving the production and performance of lignocellulolytic enzymes. We also review the progress in fermentation process optimization regarding the on-site production of lignocellulolytic enzymes using Penicillium species, and suggest prospect of future work from the perspective of building a "sugar platform" for the biorefinery of lignocellulosic biomass.


Asunto(s)
Celulasa , Penicillium , Biomasa , Celulasa/metabolismo , Fermentación , Hongos/metabolismo , Lignina/metabolismo
9.
Food Chem ; 351: 129328, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33647697

RESUMEN

A part of the fungicides used in foliar treatment penetrates into the soil. This study describes changes in the bioavailability of (essential) elements in soil, fructification, the amount of green biomass and the production of phenolic compounds related solely to the presence of triazoles (penconazole and cyproconazole) in soil, injected as a single compound or their mixture. The triazoles presence has substantially affected the bioavailability of Fe, Cu and Zn in soil. The amount of green biomass has significantly decreased, whereas the chlorophylls a and b have not been affected. As a potential mark of plant stress, the fruits of the treated variants are significantly bigger. The content of phenolics in tomato peel (e.g. quercetin, quercitrin, hesperidin, naringin, and chlorogenic, salicylic and p-coumaric acid) has been quantified. The biggest changes (increase/decrease) have been observed in the contents of p-coumaric and chlorogenic acid, quercetin and quercitrin.


Asunto(s)
Biomasa , Frutas/efectos de los fármacos , Frutas/crecimiento & desarrollo , Lycopersicon esculentum/efectos de los fármacos , Fenoles/metabolismo , Suelo/química , Triazoles/farmacología , Disponibilidad Biológica , Fungicidas Industriales/análisis , Fungicidas Industriales/farmacología , Lycopersicon esculentum/crecimiento & desarrollo , Lycopersicon esculentum/metabolismo , Triazoles/análisis
10.
Food Chem ; 351: 129264, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33662908

RESUMEN

The valorization of the brewer's spent grain (BSG) generated in a craft beer industry was studied by subcritical water hydrolysis in a semi-continuous fixed-bed reactor. Temperature was varied from 125 to 185 °C at a constant flow rate of 4 mL/min. Biomass hydrolysis yielded a maximum of 78% of solubilized protein at 185 °C. Free amino acids presented a maximum level at 160 °C with a value of 55 mg free amino acids/gprotein-BSG. Polar amino acid presented a maximum at lower temperatures than non-polar amino acids. The maximum in total phenolic compounds was reached at 185 °C. This maximum is the same for aldehyde phenolic compounds such as vanillin, syringic and protocatechuic aldehyde; however, for hydroxycinnamic acids, such as ferulic acid and p-coumaric, the maximum was obtained at 160 °C. This allows a fractionation of the bioactive compounds. Subcritical water addresses opportunities for small breweries to be incorporated within the biorefinery concept.


Asunto(s)
Fraccionamiento Químico/métodos , Grano Comestible/química , Proteínas de Plantas/aislamiento & purificación , Residuos , Agua/química , Bebidas Alcohólicas/análisis , Biomasa , Ácidos Cumáricos/análisis , Hidrólisis , Fenoles/análisis , Proteínas de Plantas/química , Factores de Tiempo
11.
J Environ Manage ; 287: 112257, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690013

RESUMEN

The economic developments around the globe resulted in the increased demand of energy, which overburdened the supply chain sources of energy. Fossil fuel reserves are exploited to meet the high demand of energy and their combustion is becoming the main source of environmental pollution. So there is dire need to find safe, renewable and sustainable energy resources. Waste to energy (WtE) may be viewed as a possible alternate source of energy, which is economically and environmentally sustainable. Municipal solid waste (MSW) is a major contributor to the development of renewable energy and sustainable environment. At present the scarcity of renewable energy resources and disposal of MSW is a challenging problem for the developing countries, which has generated a wide ranging socioeconomic and environmental problems. This situation stimulates the researchers to develop alternatives for converting WtE under a variety of scenarios. Herein, the present scenario in developing the WtE technologies such as, thermal conversion methods (Incineration, Gasification, Pyrolysis, Torrefaction), Plasma technology, Biochemical methods, Chemical and Mechanical methods, Bio-electrochemical process, Mechanical biological treatment (MBT), Photo-biological processes for efficacious energy recovery and the challenges confronted by developing and developed countries. In this review, a framework for the evaluation of WtE technologies has been presented for the ease of researchers working in the field. Furthermore, this review concluded that WtE is a potential renewable energy source that will partially satisfy the demand for energy and ensure an efficient MSW management to overcome the environmental pollution.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Biomasa , Incineración , Residuos Sólidos , Tecnología
12.
J Environ Manage ; 287: 112295, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33706096

RESUMEN

There is an urgent need to meet the demand of water and nutrients by their reuse and recycling to gratify sustainable food production system and resource conservation. Chlorella minutissima was found to be very effective in the removal of electrical conductivity (EC), total dissolved solids, phosphorous (P), potassium (K), ammonium, nitrate, biological oxygen demand (BOD5) and chemical oxygen demand (COD) of sewage wastewater. We tested the effects of phycoremediated algal biomass addition to soil in field plots of baby corn and spinach, on plant growth, yield and soil chemical properties. The application of 100% nitrogen (N) fertilizer by algal biomass lead to higher economic yield of spinach and baby corn than recommended dose of mineral fertilizers. The available N and P content in experimental plots applied with algae biomass as biofertilizers were significantly higher than other treatments. The soil enzymes, such as urease, nitrate reductase, and dehydrogenase were analysed during the cropping season of baby corn and spinach. The soil supplied with 100% N by algae biomass (C. minutissima) significantly (P < 0.05) increased the dehydrogenase activity in spinach grown soil. While the nitrate reductase activity in soil supplied with algal manure was maximum (0.13 mg NO2-N produced g-1 soil 24 h-1) and significantly higher than other treatments in baby corn grown soil. This study revealed that phycoremediation coupled with biofertilizers production from algae biomass is a recycling and resource conservation exercise to reduce eutrophication, recycling of wastewater, recycling of plant nutrients and improvement of the soil quality in circular economy fertilization.


Asunto(s)
Chlorella , Biomasa , Producción de Cultivos , Fertilización , Fertilizantes/análisis , Nitrógeno , Suelo
13.
J Environ Manage ; 287: 112293, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33714048

RESUMEN

This paper aims to investigate the causal relationship among renewable energy technologies, biomass energy consumption, per capita GDP, and CO2 emissions for Germany. We constructed an innovative algorithm, the Quantum model, and applied it with Machine Learning experiments - through a software capable of emulating a quantum system - to data over the period of 1990-2018. This process is possible after eliminating the "irreversibility" of classical computations (unitary transformations) by making the process "reversible". The empirical findings support the powerful role of biomass energy in reducing carbon dioxide emissions, although the effect of renewable energy technology displays a much stronger magnitude. Moreover, income remains an important determinant of environmental pollution in Germany.


Asunto(s)
Dióxido de Carbono , Energía Renovable , Biomasa , Dióxido de Carbono/análisis , Desarrollo Económico , Contaminación Ambiental/análisis , Alemania
14.
J Environ Manage ; 287: 112261, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33721760

RESUMEN

This research evaluates the impacts of the Renewable Portfolio Standard (RPS) on renewable electricity capacity using annual data spanning 47 states between 1990 and 2014 in the United States. RPS is a state-level policy that requires electricity suppliers to include a certain fraction of renewable electricity in their total electricity sales over a specified time period. Following nuanced identification strategies, generalized difference-in-difference method is used to transform observational data into a quasiexperimental setting to mitigate against potentially inconsistent estimator or selection bias concerns vis-à-vis the adoption of RPS across states. Generalized least squares with panel corrected standard errors and spatial econometric methods are selected as estimation techniques. The results show that RPS adoption drives more than one third increase in overall renewable electricity capacity. RPS impacts on total electricity capacity remain significantly positive with consistent estimates across modeling scenarios. However, the results reveal that impacts of heterogeneous RPS attributes differ across competing sources of renewable electricity. The impacts are positively significant for solar and wind capacity with the largest impact on wind capacity, while they are insignificant or significantly negative for biomass and geothermal capacity. The significantly positive contribution of renewable energy certificates provision and manifestation of spatial spillover effects indicate the regional marketing possibilities of renewable energy. The results imply that scaling up RPS proliferation across the states and specifying RPS targets by renewable energy sources at least up to the point when renewable energy sector achieves efficiency gains (economies of scales and allocative efficiency) or better alternatives to the RPS become available (e.g., least-cost carbon pricing policy), can play critical roles to exert transformative advances in renewable electricity sector.


Asunto(s)
Energía Renovable , Viento , Biomasa , Electricidad , Estándares de Referencia , Estados Unidos
15.
Water Res ; 196: 117038, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33751972

RESUMEN

It is necessary to develop sustainable technologies for centrate wastewater (CW) and biogas treatment from sludge anaerobic digestion (AD) systems in an environmentally friendly and economical manner. The microalgae-based bioremediation approach presents a competitive alternative due to its capacity for nutrient recovery and carbon sequestration. However, process instabilities and operating challenges limit its development and implementation largely due to the complexities in the CW and biogas. In this study, the evolved native microalgal consortium (ENMC) was firstly developed using the gradual stress increase method to enhance their adaptation in high ammonium condition. The supplementation of local snow (with Ca2+ and Mg2+) and biogas into CW significantly enhanced ENMC growth through batch tests. Subsequently, an integrated ENMC-snow (ENMCS) system was proposed consisting of a hydrolysis-acidification reactor (HAR), biogas upgrade reactor, and photobioreactor (PBR). The ENMCS system was systematically investigated under both batch and semi-continuous operations, by adjusting primary process parameters including the fill ratio, feeding time, hydraulic retention time (HRT), wastewater pretreatment, and PBR type. It was eventually optimized as a 24 h, 70% fermented CW diluted with 30% snow water, semi-continuous feeding system with a fill ratio of 50% and HRT of 6 d in an open-PBR. Long-term operation (310 days) showed superior biomass yield (0.3059 ± 0.0039 g/(L•d)) and nutrient removal efficiencies (95.6 ± 0.13% and 90.8 ± 0.44% for NH4+-N and PO43--P removal). Meanwhile, biogas was upgraded with an 82.2% CO2 reduction. The economic and environmental analysis further demonstrated the ENMCS system as an effective alternative for the bioremediation of AD effluents while simultaneously producing value-added biomass, especially applicable to snowy regions.


Asunto(s)
Microalgas , Biodegradación Ambiental , Biocombustibles/análisis , Biomasa , Nieve , Aguas Residuales
16.
Water Res ; 196: 117053, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33774349

RESUMEN

Understanding the climatic drivers of eutrophication is critical for lake management under the prism of the global change. Yet the complex interplay between climatic variables and lake processes makes prediction of phytoplankton biomass a rather difficult task. Quantifying the relative influence of climate-related variables on the regulation of phytoplankton biomass requires modelling approaches that use extensive field measurements paired with accurate meteorological observations. In this study we used climate and lake related variables obtained from the ERA5-Land reanalysis dataset combined with a large dataset of in-situ measurements of chlorophyll-a and phytoplankton biomass from 50 water bodies to develop models of phytoplankton related responses as functions of the climate reanalysis data. We used chlorophyll-a and phytoplankton biomass as response metrics of phytoplankton growth and we employed two different modelling techniques, boosted regression trees (BRT) and generalized additive models for location scale and shape (GAMLSS). According to our results, the fitted models had a relatively high explanatory power and predictive performance. Boosted regression trees had a high pseudo R2 with the type of the lake, the total layer temperature, and the mix-layer depth being the three predictors with the higher relative influence. The best GAMLSS model retained mix-layer depth, mix-layer temperature, total layer temperature, total runoff and 10-m wind speed as significant predictors (p<0.001). Regarding the phytoplankton biomass both modelling approaches had less explanatory power than those for chlorophyll-a. Concerning the predictive performance of the models both the BRT and GAMLSS models for chlorophyll-a outperformed those for phytoplankton biomass. Overall, we consider these findings promising for future limnological studies as they bring forth new perspectives in modelling ecosystem responses to a wide range of climate and lake variables. As a concluding remark, climate reanalysis can be an extremely useful asset for lake research and management.


Asunto(s)
Lagos , Fitoplancton , Biomasa , Clorofila , Clorofila A , Ecosistema , Eutrofización , Lagos/análisis
17.
Molecules ; 26(4)2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33669948

RESUMEN

To demonstrate the importance of sample preparation used in Fourier transform infrared (FTIR) spectroscopy of microbiological materials, bacterial biomass samples with and without grinding and after different drying periods (1.5-23 h at 45 °C), as well as biogenic selenium nanoparticles (SeNPs; without washing and after one to three washing steps) were comparatively studied by transmission FTIR spectroscopy. For preparing bacterial biomass samples, Azospirillum brasilense Sp7 and A. baldaniorum Sp245 (earlier known as A. brasilense Sp245) were used. The SeNPs were obtained using A. brasilense Sp7 incubated with selenite. Grinding of the biomass samples was shown to result in slight downshifting of the bands related to cellular poly-3-hydroxybutyrate (PHB) present in the samples in small amounts (under ~10%), reflecting its partial crystallisation. Drying for 23 h was shown to give more reproducible FTIR spectra of bacterial samples. SeNPs were shown to contain capping layers of proteins, polysaccharides and lipids. The as-prepared SeNPs contained significant amounts of carboxylated components in their bioorganic capping, which appeared to be weakly bound and were largely removed after washing. Spectroscopic characteristics and changes induced by various sample preparation steps are discussed with regard to optimising sample treatment procedures for FTIR spectroscopic analyses of microbiological specimens.


Asunto(s)
Azospirillum/química , Nanopartículas/análisis , Selenio/análisis , Biomasa , Espectroscopía Infrarroja por Transformada de Fourier
18.
Carbohydr Polym ; 260: 117814, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712158

RESUMEN

Lytic polysaccharide monooxygenases (LPMOs), monocopper enzymes that oxidatively cleave recalcitrant polysaccharides, have important biotechnological applications. Thermothelomyces thermophilus is a rich source of biomass-active enzymes, including many members from auxiliary activities family 9 LPMOs. Here, we report biochemical and structural characterization of recombinant TtLPMO9H which oxidizes cellulose at the C1 and C4 positions and shows enhanced activity in light-driven catalysis assays. TtLPMO9H also shows activity against xyloglucan. The addition of TtLPMO9H to endoglucanases from four different glucoside hydrolase families (GH5, GH12, GH45 and GH7) revealed that the product formation was remarkably increased when TtLPMO9H was combined with GH7 endoglucanase. Finally, we determind the first low resolution small-angle X-ray scattering model of the two-domain TtLPMO9H in solution that shows relative positions of its two functional domains and a conformation of the linker peptide, which can be relevant for the catalytic oxidation of cellulose and xyloglucan.


Asunto(s)
Celulasas/metabolismo , Celulosa/metabolismo , Activación Enzimática/efectos de la radiación , Proteínas Fúngicas/metabolismo , Luz , Oxigenasas de Función Mixta/metabolismo , Sordariales/enzimología , Biomasa , Catálisis , Celulosa/química , Proteínas Fúngicas/química , Proteínas Fúngicas/clasificación , Proteínas Fúngicas/genética , Glucanos/química , Glucanos/metabolismo , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/clasificación , Oxigenasas de Función Mixta/genética , Oxidación-Reducción , Filogenia , Dominios Proteicos , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Dispersión del Ángulo Pequeño , Estereoisomerismo , Especificidad por Sustrato , Difracción de Rayos X , Xilanos/química , Xilanos/metabolismo
19.
Ecotoxicol Environ Saf ; 214: 112125, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33714138

RESUMEN

Phytomanagement is proposed as a cost-effective and environmentally-friendly suggestion for sustainable use of large metal-contaminated areas. In the current work, the energy crop miscanthus (Miscanthus × giganteus) was grown in ex situ conditions on agricultural soils presenting a Cd, Pb and Zn contamination gradient. After 93 days of culture, shoot and root growth parameters were measured. Soils and plants were sampled as well to study the TE accumulation in miscanthus and the effects of this plant on TE mobility in soils. Results demonstrated that miscanthus growth depended more on the soils silt content rather than TE-contamination level. Moreover, soil organic carbon at T93 increased in the soils after miscanthus cultivation by 25.5-45.3%, whereas CaCl2-extractible TEs decreased due to complex rhizosphere processes driving plant mineral uptake, and organic carbon inputs into the rhizosphere. In the contaminated soils, miscanthus accumulated Cd, Pb and Zn mainly in roots (BCF in roots: Cd " Zn > Pb), while strongly reducing the transfer of these elements from soil to all organs and from roots to rhizomes, stems and leaves (average TFs: 0.01-0.06, 0.11-1.15 and 0.09-0.79 corresponding to Cd, Pb and Zn respectively). Therefore, miscanthus could be considered a TE-excluder, hence a potential candidate crop for coupling phytostabilization and biomass production on the studied Metaleurop TE-contaminated soils.


Asunto(s)
Metales Pesados/metabolismo , Poaceae/metabolismo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , Biomasa , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/metabolismo , Poaceae/crecimiento & desarrollo , Rizosfera
20.
Nat Commun ; 12(1): 1785, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741981

RESUMEN

Tropical secondary forests sequester carbon up to 20 times faster than old-growth forests. This rate does not capture spatial regrowth patterns due to environmental and disturbance drivers. Here we quantify the influence of such drivers on the rate and spatial patterns of regrowth in the Brazilian Amazon using satellite data. Carbon sequestration rates of young secondary forests (<20 years) in the west are ~60% higher (3.0 ± 1.0 Mg C ha-1 yr-1) compared to those in the east (1.3 ± 0.3 Mg C ha-1 yr-1). Disturbances reduce regrowth rates by 8-55%. The 2017 secondary forest carbon stock, of 294 Tg C, could be 8% higher by avoiding fires and repeated deforestation. Maintaining the 2017 secondary forest area has the potential to accumulate ~19.0 Tg C yr-1 until 2030, contributing ~5.5% to Brazil's 2030 net emissions reduction target. Implementing legal mechanisms to protect and expand secondary forests whilst supporting old-growth conservation is, therefore, key to realising their potential as a nature-based climate solution.


Asunto(s)
Secuestro de Carbono , Carbono/metabolismo , Cambio Climático , Bosques , Clima Tropical , Algoritmos , Biomasa , Brasil , Conservación de los Recursos Naturales/métodos , Ecosistema , Fuego , Agricultura Forestal , Geografía , Modelos Teóricos , Imágenes Satelitales/métodos , Árboles/crecimiento & desarrollo , Árboles/metabolismo
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