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1.
Anal Chim Acta ; 1159: 338418, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33867032

RESUMO

Favipiravir, a promising antiviral agent, is undergoing clinical trials for the potential treatment of the novel coronavirus disease 2019 (COVID-19). This is the first report for the electrochemical activity of favipiravir and its electroanalytical sensing. For this purpose, the effect of cationic surfactant, CTAB was demonstrated on the enhanced accumulation of favipiravir at the surface of cathodically pretreated boron-doped diamond (CPT-BDD) electrode. At first, the electrochemical properties of favipiravir were investigated in the surfactant-free solutions by the means of cyclic voltammetry. The compound presented a single oxidation step which is irreversible and adsorption controlled. A systematic study of various operational conditions, such as electrode pretreatment, pH of the supporting electrolyte, concentration of CTAB, accumulation variables, and instrumental parameters on the adsorptive stripping response, was examined using square-wave voltammetry. An oxidation signal at around +1.21 V in Britton-Robinson buffer at pH 8.0 containing 6 × 10-4 M CTAB allowed to the adsorptive stripping voltammetric determination of favipiravir (after 60 s accumulation step at open-circuit condition). The process could be used in the concentration range with two linear segments of 0.01-0.1 µg mL-1 (6.4 × 10-8-6.4 × 10-7 M) and 0.1-20.0 µg mL-1 (6.4 × 10-7-1.3 × 10-4 M). The limit of detection values were found to be 0.0028 µg mL-1 (1.8 × 10-8 M), and 0.023 µg mL-1 (1.5 × 10-7 M) for the first and second segments of calibration graph, respectively. The feasibility of developed methodology was tested to the analysis of the commercial tablet formulations and model human urine samples.


Assuntos
Amidas/química , Antivirais/química , Boro , Diamante , Eletrodos , Pirazinas/química , Tensoativos/química , Humanos , /efeitos dos fármacos
2.
J Chromatogr A ; 1645: 462130, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-33848663

RESUMO

Inspired by the outstanding functions of 3-aminopropyltriethoxysilane (APTES), which can be used for functionalization of both covalent organic frameworks (COFs) and substrate surfaces, herein, a proof-of-concept demonstration was carried out by one-step synthesis and immobilization of COF-1 in capillary. COF-1 was grown on the inner wall of capillary using APTES, which played a triple role of catalyst, stabilizer, and connecting arm during the process. The immobilization of COF-1 on silicon surface was confirmed by scanning electron microscopy. Moreover, COF-1 modified capillary (COF-1@capillary) column exhibited excellent performance in the electrochromatographic separation of amino acids. High resolution and separation efficiency (225,378 plates/m for 4-methylbiphenyl) were successfully achieved. Separation of methylbenzene, styrene, ethylbenzene, chlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, 4-methylbiphenyl, naphthalene, and 4-vinylbipheny in the electro-driven mode confirmed the successful growth of COF-1 on the inner wall of capillary. The developed facile method for the immobilization of COF-1 may pave the way for further application prospects of boron-based COFs.


Assuntos
Eletrocromatografia Capilar/métodos , Estruturas Metalorgânicas/química , Derivados de Benzeno/análise , Derivados de Benzeno/química , Derivados de Benzeno/isolamento & purificação , Boro/química , Propilaminas/química , Silanos/química
3.
Ecotoxicol Environ Saf ; 214: 112083, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33676054

RESUMO

Boron (B), an essential element for increasing seed yield and germinability in alfalfa (Medicago sativa L.), plays a vital role in its reproductive processes. However, effects of B stress on physiological and proteomic changes in reproductive organs related to alfalfa seed yield and germinability are poorly understood. In order to gain a better insight into B response or tolerance mechanisms, field trials were designed for B deficiency (0 mg B L-1), B sufficiency (800 mg B L-1), and B surplus (1600 mg B L-1) application during alfalfa flowering to analyze the proteomics and physiological responses of alfalfa 'Aohan' reproductive organs. Results showed that B deficiency weakened the stress-responsive ability in these organs, while B surplus reduced the sugar utilization of 'Aohan' flowers and caused lipid membrane peroxidation in 'Aohan' seeds. In addition, four upregulated stress responsive proteins (ADF-like protein, IMFP, NAD(P)-binding Rossmann-fold protein and NAD-dependent ALDHs) might play pivotal roles in the response of 'Aohan' reproductive organs to conditions of B deficiency and B surplus. All of the above results would be helpful to understand the tolerance mechanisms of alfalfa reproductive organs to both B deficiency and B surplus conditions, and also to give insight into the regulatory role of B in improving seed yield and germinability in alfalfa seed production. In summary, B likely plays a structural and regulatory role in relation to lipid metabolism, carbohydrate metabolism, amino acid metabolism, and signal transduction, thus regulates alfalfa reproductive processes eventually affecting the seed yield and germinability of alfalfa seeds.


Assuntos
Boro/fisiologia , Medicago sativa/fisiologia , Boro/metabolismo , Metabolismo dos Carboidratos , Flores , Genitália , Germinação , Medicago sativa/metabolismo , Proteômica/métodos , Sementes/metabolismo
4.
Water Sci Technol ; 83(6): 1357-1368, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33767042

RESUMO

Conventional biological treatments used in most Indonesian landfill sites are mostly ineffective in treating stabilized landfill leachates to meet the standard regulation. Thus, a combination of biological and electrochemical process is offered to successfully treat leachates containing a high concentration of organic and nitrogenous compounds. In this study, a moving bed biofilm reactor (MBBR) was applied prior to electrochemical oxidation by using boron-doped diamond (BDD), Ti/IrO2, and Ti/Pt anodes with applied current of 350, 400 and 450 mA. The objectives were to investigate the effect of anode type and the applied current on the removal of organics as well as total nitrogen from the MBBR-treated leachate with electrochemical oxidation. The optimum removal of chemical oxygen demand (COD) observed on the Ti/Pt anode was 78% by applying 400 mA, with an estimated energy of 56.7 Wh g L-1. In the case of Ti/IrO2 and BDD anodes, the optimum removal of COD was 76 and 85% with an energy consumption of 58.9 and 36.9 Wh g L-1, respectively, both achieved at 350 mA. Although all anodes showed less-satisfactory performances for total nitrogen reduction, around 46-95% removal of nitrogenous compounds was achieved by MBBR, with their partial conversion to nitrates.


Assuntos
Diamante , Poluentes Químicos da Água , Biofilmes , Reatores Biológicos , Boro , Eletrodos , Indonésia , Oxirredução , Titânio , Poluentes Químicos da Água/análise
5.
Bratisl Lek Listy ; 122(4): 263-269, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729819

RESUMO

BACKGROUND: Seven dioxaborole compounds are investigated in this study. Structural and spectral characterizations are done at the M062X/6-31+G(d,p) level in water. Active sites of these compounds are determined by contour plots of frontier molecular orbital and molecular electrostatic potential (MEP) maps. Electrophilic and nucleophilic attack regions are determined. Since SARS-CoV-2 is a worldwide health problem, antiviral properties of studied boron-containing compounds are investigated by molecular docking calculations. In addition to these calculations, MM/PSBA calculations are performed. RESULTS AND CONCLUSION: It is found that the studied boron compounds can be good drug candidates against the main protease of SARS-CoV-2, while the best of them is 4,6-di-tert-butyl-2-(4-methoxyphenyl)benzo[d][1,3,2] dioxaborole (B2) (Tab. 3, Fig. 8, Ref. 23).


Assuntos
Antivirais , Antivirais/farmacologia , Antivirais/uso terapêutico , Boro , Compostos de Boro/farmacologia , Humanos , Simulação de Acoplamento Molecular , Proteínas não Estruturais Virais
6.
J Environ Manage ; 285: 112101, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33609977

RESUMO

The bioavailability of heavy metals in compost is critical for their agronomic value. The effect of inorganic additives (rock phosphate, PR and boron waste, BW) on Copper (Cu) and Zinc (Zn) bioavailability during co-compost of swine manure and rice straw was assessed using sequential extraction procedure (European Community Bureau of Reference). The result showed that both additives, applied at rates of 2.5%-7.5% (w/w) could promote the change of exchangeable Cu and reducible Cu into oxidizable Cu, thereby reducing their bioavailability factor (BF) by 15.5%-47.2%. While additives provided no significant reduction in BF of Zn, the shift from exchangeable Zn into reducible Zn can still reduce the mobility of Zn. Based on redundancy analysis (RDA), organic matter (OM) and electrical conductivity (EC) were identified as the most important controlling factors for redistribution of Cu and Zn fractions during composting. The inorganic additives strengthened the passivation of Cu and Zn bioavailability by stimulating OM degradation. The 7.5% (w/w) rock phosphate showed best passivating effect on the bioavailability of Cu.


Assuntos
Compostagem , Metais Pesados , Animais , Boro , Cobre/análise , Esterco , Metais Pesados/análise , Fosfatos , Solo , Suínos , Zinco
7.
Artigo em Inglês | MEDLINE | ID: mdl-33546264

RESUMO

The present study synthesized nano-magnetite (Fe3O4) from milled steel chips using the high energy ball milling (HEBM) method, characterized it, and then utilized it as a sorbent to remediate boron concentration at various pH (4-9), dosages (0.1-0.5 g), contact times (20-240 min), and initial concentrations (10-100 mg/L). The nano-sorbents were characterized based on SEM structure, elemental composition (EDX), surface area analysis (BET), crystallinity (XRD), and functional group analysis (FTIR). The highest adsorption capacity of 8.44 mg/g with removal efficiency of 84% was attained at pH 8, 0.5 g dosage, contact time of 180 min, and 50 mg/L initial concentration. The experimental data fit best with the pseudo-second-order kinetic model with R2 of 0.998, while the Freundlich adsorption isotherm describes the adsorption process with an R2 value of 0.9464. A regeneration efficiency of 47% was attained even after five cycles of reusability studies. This efficiency implies that the nano-magnetite has the potential for sustainable industrial application.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Boro , Óxido Ferroso-Férrico , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/análise
8.
Plant Physiol Biochem ; 161: 36-45, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33561659

RESUMO

Boron (B) is an essential micronutrient for the plant normal growth. In Arabidopsis, NIP6;1 is a boric acid channel required for the proper distribution of boric acid, especially in the nodal regions of shoots. BnaA02.NIP6;1a, a homologous gene of AtNIP6;1 in Brassica napus, was reported to play a key role in B transport activity. However, little is known about the other functions of BnaA02.NIP6;1a in Brassica napus. In this study, we found that BnaA02.NIP6; 1a was localized in both plasma membrane and cytoplasm, which was different from that in Arabidopsis. The transgenic Arabidopsis plant containing a BnaA02.NIP6;1a promoter driven GUS reporter gene displayed strong GUS activity in roots, stems, leaves, especially in buds and open flowers, which are different from the expression pattern from its homologous gene in Arabidopsis. Silencing BnaA02.NIP6;1a repressed vegetative growth under B-deficient condition in Brassica napus. More importantly, knockdown of BnaA02.NIP6;1a in rapeseed resulted in the reduction of boron accumulation in the flower under boron deficiency and lead to severe sterility, which has not yet been reported before. Furthermore, nip6;1 mutant in Arabidopsis only showed the loss of apical dominance phenotype under boron deficiency at reproductive stage, whereas BnaA02.NIP6;1 RNAi lines exhibited large amounts of abnormal development of the inflorescence as compared with the wild type under boron limitation. Taken together, our results demonstrate that BnaA02.NIP6;1a encodes a boron transporter required for plant development under boron deficiency in Brassica napus, which shows its novel and diverse function in rapeseed compared with model plant Arabidopsis.


Assuntos
Brassica napus , Boro/metabolismo , Brassica napus/genética , Brassica napus/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/metabolismo , Desenvolvimento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
9.
Plant Physiol Biochem ; 161: 156-165, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33609922

RESUMO

Ammonium (NH4+) and nitrate (NO3-) conversely alter pH of the rooting medium, and thus differentially affect the equilibrium between boric acid and borate in soil solution. This can alter boron (B) uptake by plants, which is passive under high, but facilitated (boric acid) or active (borate) under low B supply. Therefore, the effect of NH4+ and NO3- forms was investigated on the growth, 10B uptake rate and accumulation, and expression of B transporters in Brassica napus grown with low (1 µM) or high (100 µM) 10B for five days in the nutrient solution. At the low 10B level, NO3--fed plants had the same specific 10B uptake rate, 10B accumulation and xylem 10B concentration as NH4NO3-fed plants but these attributes were reduced at the high 10B level. BnaBOR1;2 and BnaNIP5;1 were upregulated in roots of NO3-fed plants at low 10B supply. NH4+-fed plants had substantially lower dry matters; due to nutrient solution acidification (2.0 units)-induced deficiency of nitrogen, potassium, magnesium, and iron in plant shoots. Reduced transpiration rates resulted in lower 10B uptake rate and accumulation in the roots and shoots of NH4+-fed plants. BnaNIP5;1 in roots, while both BnaBOR1;2 and BnaNIP5;1 in shoots were upregulated in NH4+-fed plants at low 10B level. Collectively, NH4+-induced acidity and consequent lowering of 10B uptake induced the upregulation of B transport mechanisms, even at marginal 10B concentrations, while NO3--induced alkalinization resulted in altered B distribution between roots and shoots due to restricted B transport, especially at higher 10B supply.


Assuntos
Compostos de Amônio , Brassica napus , Boro , Nitratos , Nitrogênio , Raízes de Plantas , Brotos de Planta
10.
Physiol Plant ; 171(4): 809-822, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33481273

RESUMO

Boron (B) is an essential mineral element for plant growth, and the seed B pool of crops can be crucial when seedlings need to establish on low-B soils. To date, it is poorly understood how B accumulation in grain crops is genetically controlled. Here, we assessed the genotypic variation of the B concentration in grains of a spring barley (Hordeum vulgare L.) association panel that represents broad genetic diversity. We found a large genetic variation of the grain B concentration and detected in total 23 quantitative trait loci (QTLs) using genome-wide association mapping. HvNIP2;2/HvLsi6, encoding a potential B-transporting membrane protein, mapped closely to a major-effect QTL accounting for the largest proportion of grain B variation. Based on transport studies using heterologous expression systems and gene expression analysis, we demonstrate that HvNIP2;2/HvLsi6 represents a functional B channel and that expression variation in its transcript level associates with root and shoot B concentrations as well as with root dry mass formation under B-deficient conditions.


Assuntos
Hordeum , Boro , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Hordeum/genética , Fenótipo , Locos de Características Quantitativas/genética
11.
Environ Monit Assess ; 193(1): 17, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33389185

RESUMO

The bioaccessibility of some elements (As, B, Cd, Cu, Fe, Mn, Ni and Zn) in soils and vegetables was determined using the physiologically based extraction test. An investigation of the geochemical phases of soils through sequential extraction methods followed by ICP-MS detection was also undertaken. Samples were collected from Iskele, Begendikler and Yolbasi villages in the Bigadic region and Yildiz village in the Susurluk region of Balikesir province, Turkey. All of these villages are close to boron mines. Principal component analysis and correlation analysis demonstrated the interrelationship between the bioaccessibility values of these elements in the gastric and intestinal extracts of soils as well as the plant samples grown in those soils and the elements' concentrations in the different soil fractions. From the bioaccessible concentrations of the elements in the intestinal phases, it was shown that the amounts of As, B, Cu, Mn and Ni in some plant samples were higher than the recommended and tolerable values for human consumption. The bioaccessibilty of these elements in the soils and plants were statistically related with the concentrations of these elements in the labile phases of the soil. The methodology adopted here would be applicable to determining interactions between elements and soil fractions and the interrelationships between bioaccessibility data and soil fractions for any soil samples.


Assuntos
Poluentes do Solo , Solo , Boro , Monitoramento Ambiental , Humanos , Poluentes do Solo/análise , Turquia , Verduras
12.
Molecules ; 26(3)2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33498632

RESUMO

Through a simple 1,3-cycloaddition reaction, three BODIPY-peptide conjugates that target the extracellular domain of the epidermal growth factor receptor (EGFR) were prepared and their ability for binding to EGFR was investigated. The peptide ligands K(N3)LARLLT and its cyclic analog cyclo(K(N3)larllt, previously shown to have high affinity for binding to the extracellular domain of EGFR, were conjugated to alkynyl-functionalized BODIPY dyes 1 and 2 via a copper-catalyzed click reaction. This reaction produced conjugates 3, 4, and 5 in high yields (70-82%). In vitro studies using human carcinoma HEp2 cells that overexpress EGFR demonstrated high cellular uptake, particularly for the cyclic peptide conjugate 5, and low cytotoxicity in light (~1 J·cm-2) and darkness. Surface plasmon resonance (SPR) results show binding affinity of the three BODIPY-peptide conjugates for EGFR, particularly for 5 bearing the cyclic peptide. Competitive binding studies using three cell lines with different expressions of EGFR show that 5 binds specifically to EGFR-overexpressing colon cancer cells. Among the three conjugates, 5 bearing the cyclic peptide exhibited the highest affinity for binding to the EGFR protein.


Assuntos
Compostos de Boro/química , Boro/química , Corantes Fluorescentes/química , Peptídeos Cíclicos/química , Porfobilinogênio/análogos & derivados , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Ligantes , Porfobilinogênio/química , Ligação Proteica , Ressonância de Plasmônio de Superfície/métodos
13.
Environ Int ; 146: 106291, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33395938

RESUMO

In this study, a boron-doped diamond (BDD) electro-oxidation technology coupled with nanofiltration membrane (EO-NF) technology was investigated for its effectiveness in removing antibiotics (i.e., sulfamethazine:SMZ) and mitigating biofouling during secondary wastewater treatment. The result showed that EO obtained an effective SMZ removal, owing to the ·OH generation observed by Electron paramagnetic resonance (EPR) analysis; complete elimination of SMZ was found under the high current density (30 mA/cm2) and long Electrolysis Time (ET = 60 min). Meanwhile, EO-NF process enabled to reduce COD content from 60 mg/L to nearly 5 mg/L. Furthermore, regardless of the effect of EO process, NF could retain most NH3-N because of the excellent performance of NF for ions rejection, and its permeate concentration was below 0.5 mg/L. EO was able to reduce membrane fouling notably, increasing the final flux (15 L/(m2·h)) of NF by 25.1% during long-term operation (240 h). Scanning electron microscopy-Energy dispersive spectrometry (SEM-EDS) showed that a porous layer formed on the vicinity of NF membrane in the case of filtrating EO effluent, in contrast to a uniform and dense biofouling layer generated during the direct NF. Besides, the content of adenosine triphosphate (ATP) and the number of bacterial colonies in the retentate of the EO-NF process were greater than those of the direct NF process. This resulted in a smaller amount of extracellular polymeric substances (EPS) attaching to the membrane surface, decreasing the tightness and hardness of the fouling layer in the case of EO, as indicated by CLSM analysis. Overall, considering its ability to effectively eliminate persistent contaminants and reduce membrane fouling, BDD-based EO is considered a promising pre-treatment option for future NF applications.


Assuntos
Incrustação Biológica , Poluentes Químicos da Água , Antibacterianos , Incrustação Biológica/prevenção & controle , Boro , Diamante , Oxirredução , Águas Residuárias , Poluentes Químicos da Água/análise
14.
Ecotoxicol Environ Saf ; 211: 111843, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33465626

RESUMO

Geothermal energy is a low-pollution energy source. However, air, soil, and water near geothermal plants may be affected by their operation. One of the largest geothermal energy sources in the world, Cerro Prieto, has a capacity of 720 MW and is located in northwest Mexico near an agricultural area. The abstracted geothermal fluids, which are enriched with arsenic (As), boron (B), lead (Pb), cadmium (Cd), and other heavy metals, are either reinjected into the aquifer or sent to an evaporation pond located in the geothermal plant. Because spills have occurred in other geothermal zones, it is important to evaluate the effect of those contaminants on the soils of the surrounding area and their possible infiltration into shallow groundwater. To that aim, soils (one chromic Vertisol and two calcic Regosols) from three sites near the Cerro Prieto Geothermal Plant were sampled to evaluate their behavior regarding As, Pb, and B retention. Batch experiments were carried out using the soils as the sorbent and geothermal water from three geothermal production wells as the sorbate. Raw water concentrations in each well were as follows: As: 0.2442 mg/L, 0.2774 mg/L, and mg/L; B: 18.409 mg/L, 13.5075 mg/L, and 16.646 mg/L; and Pb: 0.22 mg/L, 0.13 mg/L, and 0.26 mg/L. The physicochemical characteristics of the soils were determined and compared to the experimental results. A good adjustment of the chromic Vertisol sample to Freundlich isotherms was observed for As (r2 > 0.9), followed by Pb (r2 = 0.61), and B (r2 > 0.5). As retention also showed a good adjustment to the Langmuir model (r2 > 0.9). The retention followed the order Pb >As ≫B in one of the two calcic Regosols, while the other only retained Pb ≫ As. Cationic exchange capacity; clay minerals; carbonate; organic matter; and iron, aluminum, and manganese amorphous and crystalline oxides influenced the soils' retention capacities. Irrigation with geothermal water could not imply a toxicity risk to plants grown in the chromic Vertisol soil due to its high Pb and As sorption capacity. Pb concentration could not be a toxicity issue in the calcic Regosols for the same reason, but As and B could be. B would be a hazard to vegetables and water due to its low or lack of retention in the three soils and also for its possible infiltration into shallow groundwater used for irrigation in the area. This study highlights the importance of maintaining adequate operation and control of the disposal of geothermal fluids in geothermal plants.


Assuntos
Arsênico/análise , Boro/análise , Água Subterrânea/química , Chumbo/análise , Poluentes do Solo/análise , Agricultura , Cádmio/química , Metais Pesados/análise , México , Solo/química
15.
Sci Total Environ ; 751: 141644, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32866830

RESUMO

Rapeseed (Brassica napus L.) is extremely sensitive to both boron (B) and phosphorus (P) deficiencies. Application of chemical fertilizers is generally considered to be an effective agronomic practice to improve crop productivity, and it also affects soil bacterial community. However, there are few studies of the effects of balanced B and P fertilizer applications on crop yield and bacterial communities. In the present study, field experiments with five P application rates (0, 45, 90, 135 and 180 kg P2O5 ha-1) and four B application rates (0, 4.5, 9 and 18 kg Na2B4O7·5H2O ha-1) were conducted in 2016-2017 and 2017-2018 to investigate their effects on seed yield and P use efficiency (PUE) of B. napus. The smallest seed yields were obtained when B or P fertilizers were not applied (P90B0 or P0B9). Balanced B and P applications benefitted yields. The P45B4.5 treatment produced greater seed yield and PUE than the P45B18 treatment, and the P180B18 treatment produced greater seed yield and PUE than the P180B4.5 treatment. Sequencing of 16S rRNA genes revealed that the P90B9 treatment had greater soil bacterial diversity, and a different bacterial community composition, compared with the P90B0 or P0B9 treatments. Overall, our results underline the importance of balanced B and P nutrition for maximal seed yield of B. napus and the effects of B and P fertilizers on the soil bacterial community of B. napus.


Assuntos
Brassica napus , Fertilizantes , Boro , Brassica napus/genética , Fósforo , RNA Ribossômico 16S/genética , Sementes , Solo
16.
Food Chem ; 338: 127924, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932079

RESUMO

An exploratory study for verifying regional geographical origin of carrots from specific production regions in Austria ("Genussregionen") was performed by combining chemical fingerprinting methods, namely n(86Sr)/n(87Sr) isotope amount ratios, multi-elemental and metabolomic pattern. Chemometric classification models were built on individual and combined datasets using (data-driven) soft independent modelling of class analogies and (orthogonal) projections to latent structures-discriminant analysis to characterise and differentiate carrots grown in five regions in Austria. A predictive ability of 97% or better (depending on the classification technique) was obtained using combined Sr isotope amount ratios and multi-elemental data. The use of data fusion strategies, in particular the mid-level option (fusion of selected variables from the different analytical platforms), allowed highly efficient (99-100%, except soft independent modelling of class analogy with 97%) and correct classification of carrot samples.


Assuntos
Daucus carota/metabolismo , Metaboloma , Metabolômica/métodos , Isótopos de Estrôncio/análise , Áustria , Boro/análise , Daucus carota/química , Análise Discriminante , Geografia , Análise dos Mínimos Quadrados , Magnésio/análise , Análise de Componente Principal , Isótopos de Estrôncio/metabolismo
17.
Chemosphere ; 263: 128202, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297165

RESUMO

Pursuing a low-cost yet sustainable material with a high performance of removing boron is necessary for replacement of the synthetic adsorbents, but remains challengeable. Herein, we fabricated an mesopore-dominated bio-based material (LS-CPAM-TA) with abundant catechol groups by the electrostatic-interaction-driven self-assembly of lignosulfonate (LS), tannic acid (TA) and cationic polyacrylamide (CPAM) for efficient removal of boron. LS-CPAM-TA presented a mesopore area of 53.9 m2/g with a mesoporous distribution of 2-25 nm, as well as a mesopore/micropore volume ratio of 129.7. Such a mesopore-rich feature not only promoted the exposure of catechol groups in TA, which served as the adsorption sites, but also contributed to enhance the fast mass transport of boron. Consequently, a maximum adsorption capacity of 119.05 mg/g was observed for LS-CPAM-TA, surpassing some reported adsorbents. Even for the low concentration boron, LS-CPAM-TA also displayd the high adsorption efficiency. Moreover, LS-CPAM-TA followed the Langmuir isotherm adsorption model, and presented the excellent regeneration performance due to its robust self-assembled structure driven by the electrostatic interaction among LS, CPAM and TA. This work would provide guidelines for target design of bio-based materials with tunable porous structure and versatile adsorption or catalytic sites for various applications.


Assuntos
Boro , Taninos , Adsorção , Catecóis , Cátions
18.
ACS Appl Mater Interfaces ; 13(1): 306-311, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33382584

RESUMO

Photothermal therapy is a new type of tumor therapy with great potential. An ideal photothermal therapy agent should have high photothermal conversion effect, low biological toxicity, and degradability. The development of novel photothermal therapy agents with these properties is of great demand. In this study, we synthesized boron quantum dots (BQDs) with an ultrasmall hydrodynamic diameter. Both in vitro and in vivo studies show that the as-synthesized BQDs have good biological safety, high photoacoustic imaging performance, and photothermal conversion ability, which can be used for photoacoustic imaging-guided photothermal agents for tumor treatment. Our investigations confirm that the BQDs hold great promise in tumor theranostic applications.


Assuntos
Boro/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Pontos Quânticos/uso terapêutico , Animais , Boro/química , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Técnicas Fotoacústicas/métodos , Pontos Quânticos/química , Nanomedicina Teranóstica/métodos
19.
Sci Total Environ ; 761: 144192, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33352340

RESUMO

The catalytic boron­hydrogen bond break is usually regarded as an important reaction both in the area of environment treatment and hydrogen energy, attracting increasing attention in the past decades. Due to the limitation of conventional noble metal-based catalyst, cost-effective transition metal-based catalysts with high activity have been recently developed to become the promising candidates. Herein, the coffee ground waste was utilized as the biochar substrate loaded with ultrafine NiCoO2 nanoparticles. The abundant function groups on the biochar substrate efficiently adsorbed the metal ions and confined the crystal growth spatially, making the NiCoO2 nanoparticles highly dispersed on the surface. Moreover, the oxygen vacancies were further created in the catalysts by a vacuum-calcination strategy to boost their catalytic activity towards boron­hydrogen bond break both in the systems of 4-nitrophenol reduction by NaBH4 and hydrogen release from NH3BH3. The results indicated that the moderate presence of oxygen vacancies could effectively accelerate the boron­hydrogen bond break and the catalytic activity performed a satisfied stability during several recycles. The theoretical calculation method was adopted to analysis and discuss the mechanism within this process. This design strategy on active catalysts not only offered a novel solution of biowaste resource reuse but also demonstrated the significant role of oxygen vacancies in energy and environmental catalysis.


Assuntos
Boro , Nanopartículas , Carvão Vegetal , Café , Ligação de Hidrogênio
20.
Biosci. j. (Online) ; 36(6): 1999-2006, 01-11-2020. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1148021

RESUMO

The boron (B) fertilization in soybean is important to ensure great yields. Boron correction must be applied in deficient soils repairing losses, exports and leaching. The objective of this study was to evaluate the effects of doses, methods and times of application of B in soybean B content and yield. The field experiments were conducted during the 2015/16 and 2016/17 cropping seasons and set as a randomized block design with nine treatments (0, 0.5, 1, 1.5, 2 kg ha-1 of B, 0.5 kg ha-1 of B mixed with NPK (02-28-18) in furrow during sowing, foliar application with 0.3 kg ha-1 of B in V4 soybean stage, foliar application with 0.3 kg ha-1 of B in R1 soybean stage, and foliar application of 0.15 kg ha-1 in V4 plus 0.15 kg ha-1 of B in R1 soybean stage) and four replications. Boric acid was the B source and the variables analyzed were: B leaf content, B exported in seeds, number of pods per plant, number of seeds per pod, weight of 100 seeds (g) and productivity (kg ha-1). The levels of B in leaf were between 30.1 and 43.8 mg kg-1 and between 65.0 and 92.6 mg kg-1 in the 2015/16 and 2016/17 growing season, respectively. Exports of B in seeds were estimated between 166 and 248 g ha-1 and between 208.9 to 260.8 g ha-1 in the 2015/16 and 2016/17 growing season, respectively. Great productivity (3,820 kg ha-1) was observed in the 2016/17 growing season, with an estimated dose of 0.95 kg ha-1 of B.


A fertilização de boro na soja é importante para garantir boas produtividades, corrigir solos deficientes e repor perdas, exportação ou lixiviação. O objetivo deste estudo foi avaliar os efeitos de doses, avaliar modos e épocas de aplicação de B na produtividade da soja. Os experimentos foram implantados na Fazenda Experimental da UEG, Campus Ipameri, nas safras 2015/2016 e 2016/2017 com delineamento em blocos ao acaso, com nove tratamentos e quatro repetições. 0,0; 0,5; 1,0; 1,5; 2,0 kg ha-1 de boro, - 0,5 kg ha-1 de B junto com NPK 2-28-18 no sulco de semeadura; aplicação foliar com 0,3 kg ha-1 de boro em V4; aplicação foliar com 0,3 kg ha-1 de boro em R1; aplicação foliar de 0,150 kg ha-1 em V4 mais 0,150 kg ha-1 de boro em R1. Foi utilizado como fonte o ácido bórico. As variáveis respostas analisadas foram: teor na folha, exportação pelos grãos, número de vagens por planta, número de grãos por vagem, massa de 100 grãos e produtividade. Os teores de B encontrados ficaram entre 30,12 e 43,83 mg kg-1 na folha de soja na safra 2015/2016 e entre 65,0 e 92,6 mg kg-1 na safra 2016/2017. As exportações de Boro foram estimadas entre 166 e 248 g ha-1 e 208,9 a 260,8 g ha-1 na primeira e segunda safra, respectivamente. Houve maior produtividade na segunda safra (3820 kg ha-1) com dose estimada de 0,95 kg ha-1


Assuntos
Soja , Boro , Micronutrientes
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