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1.
J Agric Food Chem ; 72(13): 6921-6930, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38516700

RESUMO

Copper (Cu) is an element widely used as a pesticide for the control of plant diseases. Cu is also known to influence a range of plant secondary metabolisms. However, it is not known whether Cu influences the levels of the major metabolites in hemp (Cannabis sativa L.), tetrahydrocannabinol (THC) and cannabidiol (CBD). This study investigated the impact of Cu on the levels of these cannabinoids in two hemp cultivars, Wife and Merlot, under field conditions, as a function of harvest time (August-September), Cu type (nano, bulk, or ionic), and dose (50, 100, and 500 ppm). In Wife, Cu caused significant temporal increases in THC and CBD production during plant growth, reaching increases of 33% and 31% for THC and 51% and 16.5% for CBD by harvests 3 and 4, respectively. CuO nanoparticles at 50 and 100 ppm significantly increased THC and CBD levels, compared to the control, respectively, by 18% and 27% for THC and 19.9% and 33.6% for CBD. These nanospecific increases coincided with significantly more Cu in the inflorescences (buds) than in the control and bulk CuO treatments. Contrarily, no temporal induction of the cannabinoids by Cu was noticed in Merlot, suggesting a cultivar-specific response to Cu. However, overall, in Merlot, Cu ions, but not particulate Cu, induced THC and CBD levels by 27% and 36%, respectively, compared to the control. Collectively, our findings provide information with contrasting implications in the production of these cannabinoids, where, dependent on the cultivar, metabolite levels may rise above the 0.3% regulatory threshold for THC but to a more profitable level for CBD. Further investigations with a wider range of hemp cultivars, CuO nanoparticle (NP) doses, and harvest times would clarify the significance and broader implications of the findings.


Assuntos
Canabidiol , Canabinoides , Cannabis , Dronabinol/farmacologia , Cobre
2.
Environ Pollut ; 344: 123335, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211874

RESUMO

The presence of per- and poly-fluoroalkyl substances (PFAS) in soils is a global concern as these emerging contaminants are highly resistant to degradation and cause adverse effects on human and environmental health at very low concentrations. Sequestering PFAS in soils using carbon-based materials is a low-cost and effective strategy to minimize pollutant bioavailability and exposure, and may offer potential long-term remediation of PFAS in the environment. This paper provides a comprehensive evaluation of current insights on sequestration of PFAS in soil using carbon-based sorbents. Hydrophobic effects originating from fluorinated carbon (C-F) backbone "tail" and electrostatic interactions deriving from functional groups on the molecules' "head" are the two driving forces governing PFAS sorption. Consequently, varying C-F chain lengths and polar functional groups significantly alter PFAS availability and leachability. Furthermore, matrix parameters such as soil organic matter, inorganic minerals, and pH significantly impact PFAS sequestration by sorbent amendments. Materials such as activated carbon, biochar, carbon nanotubes, and their composites are the primary C-based materials used for PFAS adsorption. Importantly, modifying the carbon structural and surface chemistry is essential for increasing the active sorption sites and for strengthening interactions with PFAS. This review evaluates current literature, identifies knowledge gaps in current remediation technologies and addresses future strategies on the sequestration of PFAS in contaminated soil using sustainable novel C-based sorbents.


Assuntos
Recuperação e Remediação Ambiental , Fluorocarbonos , Nanotubos de Carbono , Poluentes do Solo , Humanos , Solo/química , Poluentes do Solo/análise
3.
ACS Omega ; 8(41): 38160-38169, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37867672

RESUMO

Form-stable phase change materials (FSPCMs) composed of poly(ethylene glycol) (PEG) encapsulated in SiO2-modified expanded graphite (EG@SiO2) were prepared and investigated for thermal energy storage behaviors. The modification of SiO2 on EG was done using a simple sol-gel method, and then the resulting EG@SiO2 was introduced to confine PEG at varying content (60-90 wt %). Surface properties (including microstructure, morphology, and functional groups), PEG adsorptivity, leakage-proof ability, and thermal energy storage of the prepared materials were thoroughly characterized and discussed. The EG@SiO2 with 15 wt % SiO2 outstandingly adsorbed PEG as compared to the pristine EG, showing up >80 wt % of PEG. As a result, PEG was well stabilized in EG@SiO2 porous network without leakage, owing to capillary force, surface tension, and hydrogen bonding interactions. The optimal 80 wt % PEG/EG@SiO2 composite possessed high crystallinity (93.5%), high thermal energy storage capacity (132.5 J/g), and excellent thermal conductivity (4.086 W/m·K). In addition, it exhibited good cycling durability after 500 repeated melting/crystallization cycles. The high thermal efficacy and inexpensiveness would make the PEG/EG@SiO2 FSPCMs suitable for scale-up applications in thermal energy storage.

4.
ACS Omega ; 7(14): 12222-12230, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35449958

RESUMO

A series of n-octadecane/mesoporous silica (C18/MS) shape-stabilized phase change materials (SSPCMs) with varying C18 content were prepared, and the effects of adsorbed C18 distributed within porous MS on the thermal properties were analyzed. As characterized, C18 was first infiltrated into the mesoporous space, resulting in a SSPCM with a maximum of ∼52 wt % C18. Additional adsorption of C18 occurred on the external surface of MS. Consequently, the optimum 70 wt % C18 SSPCM had no C18 leakage and exhibited a heat storage capacity of 135.6 J/g and crystallinity of 83.5%, which were much larger than those of 52 wt % C18 SSPCM (60.2 J/g and 68.2%, respectively). The prepared C18/MS SSPCMs showed excellent thermal stability and thermal reliability up to 1000 accelerated thermal cycle tests. Moreover, the C18/MS SSPCM incorporated in gypsum effectively reduced the temperature changes compared with the original gypsum, suggesting the promising application of the prepared C18/MS SSPCM for energy-saving building applications.

5.
Food Chem ; 373(Pt B): 131469, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34731813

RESUMO

An ethanol extract of avocado seed (TN-1) and six smaller fractions (PD-1 to PD-6) were prepared. Most of the extracts exhibited scavenging DPPH radical, reducing Fe3+ to Fe2+, and inhibiting polyphenoloxidase, consistently matching with their high polyphenolic content (p < 0.05). Most of the 47 compounds identified from TN-1 were classified into phenolic acid, condensed tannin, flavonoid, fatty acids, and alkaloids. Two extracts TN-1 and PD-2 (0.025%, w/v) were used to treat white-leg shrimp and the quality changes were evaluated compared to those treated with sodium metabisulfite (1.25%, w/v) and controls (without treatment) during 8-day storage at 2 °C. Changes in melanosis scores, lipid peroxidation, pHs, microorganisms, and nutrient in shrimps treated with the extracts were comparable to or even much better than others. These results promise a potential use of avocado seed extract as a cost-effective, eco-friendly, and effective alternative to commercial additives in shrimp storage.


Assuntos
Persea , Antioxidantes , Flavonoides , Peroxidação de Lipídeos , Extratos Vegetais
6.
Prev Nutr Food Sci ; 26(2): 209-218, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34316486

RESUMO

Melanosis in shrimp usually leads to reduction in its shelf life and quality, which causes a significant loss in economic value of shrimp products. This study reports potential applications of nine ethanolic extracts of by-products, i.e., peel and/or seed from three Vietnamese avocado varieties as effective inhibitors of melanosis in whiteleg shrimp. Six out of nine shrimp samples treated with the prepared extracts (0.025%, w/v) reduced melanosis and lipid oxidation more significantly as compared to those treated with sodium metabisulfite (SMS, 1.25%, w/v) and control groups (treated with water) during 8-day storage at 4°C (P<0.05). These six extracts had mean gray values ranging from 47.0±0.7 to 57.3±0.4% were lower than those treated with SMS (mean gray of 39.8±0.4%). The inhibition of melanosis and lipid oxidation in shrimp for these extracts could be attributed to their high content of polyphenols [total phenolic content (TPC) from 44.5±1.1 to 144.7±1.9 mg gallic acid equivalents/g dried weight] and strong antioxidant activities [including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP), and tyrosinase enzyme inhibition]. Pearson statistical analysis showed strong correlation for melanosis inhibition to TPC and DPPH scavenging (r>0.80) followed by tyrosinase inhibition and FRAP (r>0.50). The findings obtained from this study suggest potential utilization of avocado by-product extracts as safe and cheap natural alternatives to traditional sulfites for anti-melanosis and shelf life extension of whiteleg shrimp.

7.
J Colloid Interface Sci ; 586: 741-747, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33198977

RESUMO

The superior removal selectivity of hydrated zirconium oxide nanoparticle-impregnated porous anion exchange resin (ZAE) highlights its use as phosphate removal adsorbent. However, most research examines selective phosphate removal performance using randomly determined single content of hydrated zirconium oxide, and thus the use of the ZAE in real applications remains limited. Therefore, this study aimed to investigate the selective phosphate removal performance of ZAE with different content of hydrated zirconium oxide nanoparticle (HZO NP, represented by zirconium content) by considering various conditions. A molybdate intermediate method was devised to fabricate ZAE with high loaded HZO by weakening the Donnan exclusion to HZO precursors produced from the fixed positively charged host. Consequently, the resultant ZAE was characterized by 17.8 wt% of zirconium. ZAE exhibited an increased selectivity to phosphate against competing ions in the synthetic and simulated real water matrices for both batch and fixed-bed modes as the zirconium content of ZAE increased. High performance was retained, and regeneration led to possible reusability. The linear correlation between selective phosphate removal performances and zirconium content indicates that the zirconium content is a fundamental factor determining the ZAE phosphate adsorption removal. The HZO NPs within ZAE slow adsorption kinetics by blocking AE pores and provide specific adsorption sites for phosphate removal by inner-sphere complexation.

8.
Environ Sci Pollut Res Int ; 26(36): 37046-37053, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31745776

RESUMO

Selective removal of trace arsenic is crucial for obtaining safe drinking water. Here, the selective adsorptive performance of arsenate (As(V)) on a hybrid ZMAE (nanoscale zirconium molybdate embedded a macroporous anion exchange resin) was examined. It was found that the As(V) adsorption efficiency of ZMAE was almost retained in the presence of competing ions (NO3- or SO42-) up an [SO42-]/[As] or [NO3-]/[As] ratio of 150/1, whereas that of bare AE (anion exchange resin) was negligible for [SO4]/[As] over 15/1. In addition, the As(V) maximum adsorption capacity of ZMAE was found to be 41.2 mg/g, which is in contrast with the negligible adsorption of bare AE under sulfate-rich condition. The enhanced arsenate selectivity of ZMAE can be attributed to the excellent selectivity of ZM NPs (zirconium molybdate nanoparticles), which contributed up to 45% of the adsorption capacity of ZMAE. The behavior of ZMAE towards arsenate was compared with that towards phosphate showing similar adsorption performances between them, which indicates the similar affinity of ZMAE towards arsenate and phosphate. Finally, ZMAE examined for fixed-bed column adsorption for As(V) removal from synthetic As(V) water was effective for up to 5100 BVs, treating As(V) from 0.1 mg/L to below 0.01 mg/L (meeting the WHO guidelines).


Assuntos
Resinas de Troca Aniônica/química , Arsênio/química , Molibdênio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Zircônio/química , Adsorção , Arseniatos , Arsênio/análise , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas , Fosfatos , Poluentes Químicos da Água/análise
9.
Water Res ; 134: 22-31, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29407648

RESUMO

Development of a selective adsorbent with an enhanced removal efficiency for phosphate from wastewater is urgently needed. Here, a hybrid adsorbent of nanoscale zirconium molybdate embedded in a macroporous anion exchange resin (ZMAE) is proposed for the selective removal of phosphate. The ZMAE consists of a low agglomeration of zirconium molybdate nanoparticles (ZM NPs) dispersed within the structure of the anion exchange (AE) resin. As major results, the phosphate adsorption capacity of the ZMAE (26.1 mg-P/g) in the presence of excess sulfate (5 mM) is superior to that of the pristine AE resin (1.8 mg-P/g) although their phosphate uptake capacity was similar in the absence of sulfate and these results were supported by the high selectivity coefficient of the ZMAE toward phosphate over sulfate (SPO4/SO4) more than 100 times compared to the pristine AE resin. This superior selective performance of the ZMAE for phosphate in the presence of sulfate ions is well explained by the role of the ZM NPs that contributed to 69% of the phosphate capacity which is based on an observation that the phosphate adsorption capacity of the ZM NPs is not affected by the presence of sulfate. In addition, the behavior of the selective phosphate removal by the ZMAE was well demonstrated by not only in the batch mode experiment with simulated Mekong river water and representative wastewater effluent but also in a column test.


Assuntos
Resinas de Troca Aniônica/química , Molibdênio/química , Nanopartículas/química , Fosfatos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Zircônio/química , Adsorção , Concentração de Íons de Hidrogênio , Águas Residuárias/química
10.
Environ Sci Pollut Res Int ; 24(31): 24235-24242, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28889227

RESUMO

Recently, nano zero-valent iron (nZVI) has emerged as an effective adsorbent for the removal of arsenic from aqueous solutions. However, its use in various applications has suffered from reactivity loss resulting in a decreased efficiency. Thus, the aim of this study was to develop an effective arsenic adsorbent as a core/shell structural nZVI/manganese oxide (or nZVI/Mn oxide) to minimize the reactivity loss of the nZVI. As the major result, the arsenic adsorption capacities of the nZVI/Mn oxide for As(V) and As(III) were approximately two and three times higher than that of the nZVI, respectively. In addition, the As(V) removal efficiency of the nZVI/Mn oxide was maintained through 4 cycles of regeneration whereas that of the nZVI was decreased significantly. The enhanced reactivity and reusability of the nZVI/Mn oxide can be successfully explained by the synergistic interaction of the nZVI core and manganese oxide shell, in which the manganese oxides participate in oxidation reactions with corroded Fe2+ and subsequently retard the release of aqueous iron providing additional surface sites for arsenic adsorption. In summary, this study reports the successful fabrication of a core/shell nZVI/Mn oxide as an effective adsorbent for the removal of arsenic from aqueous solutions.


Assuntos
Arsênio/análise , Nanopartículas Metálicas/química , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Purificação da Água , Adsorção , Arsênio/química , Ferro/química , Compostos de Manganês/química , Óxidos/química , Poluentes Químicos da Água/química
11.
Springerplus ; 5(1): 1789, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27795931

RESUMO

BACKGROUND: Based on some previous research, the chalcone derivatives exhibited potent xanthine oxidase inhibitory activity, e.g. sappanchalcone (7), with IC50 value of 3.9 µM, was isolated from Caesalpinia sappan. Therefore, objectives of this research are design and synthesis of 7 and other chalcone derivatives by Claisen-Schmidt condensation and then evaluate their XO inhibitory activity. RESULTS: Fifteen chalcone derivatives were synthesized by Claisen-Schmidt condensation, and were evaluated for XO inhibitory activity. Nine out of 15 synthetic chalcones showed inhibitory activity (3; 5-8; 10-13). Sappanchalcone derivatives (11) (IC50, 2.5 µM) and a novel chalcone (13) (IC50, 2.4 µM) displayed strong xanthine oxidase inhibitory activity that is comparable to allopurinol (IC50, 2.5 µM). The structure-activity relationship of these chalcone derivatives was also presented. CONCLUSIONS: It is the first research on synthesis sappanchalcone (7) by Claisen-Schmidt condensation. The overall yield of this procedure was 6.6 %, higher than that of reported procedure (4 %). Design, synthesis, and evaluation of chalcone derivatives were carried out. This result suggests that the chalcone derivative can be used as potential non-purine XO inhibitors.Graphical abstractThe chalcone derivatives as potential non-purine xanthine oxidase inhibitors.

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