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1.
Scand J Med Sci Sports ; 34(3): e14595, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38458991

RESUMO

We investigated the acute effects of caffeine supplementation (6 mgï½¥kg-1 ) on 60-m sprint performance and underlying components with a step-to-step ground reaction force measurement in 13 male sprinters. After the first round sprint as a control, caffeine supplementation-induced improvement in 60-m sprint times (7.811 s at the first versus 7.648 s at the second round, 2.05%) were greater compared with the placebo condition (7.769 s at the first versus 7.768 s at the second round, 0.02%). Using average values for every four steps, in the caffeine condition, higher running speed (all six step groups), higher step frequency (5th-16th and 21st-24th step groups), shorter support time (all the step groups except for 13th-16th step) and shorter braking time (9th-24th step groups) were found. Regarding ground reaction forces variables, greater braking mean force (13th-19th step group), propulsive mean force (1st-12th and 17th-20th step groups), and effective vertical mean force (9th-12th step group) were found in the caffeine condition. For the block clearance phase at the sprint start, push-off and reaction times did not change, while higher total anteroposterior mean force, average horizontal external power, and ratio of force were found in the caffeine condition. These results indicate that, compared with placebo, acute caffeine supplementation improved sprint performance regardless of sprint sections during the entire acceleration phase from the start through increases in step frequency with decreases in support time. Moreover, acute caffeine supplementation promoted increases in the propulsive mean force, resulting in the improvement of sprint performance.


Assuntos
Desempenho Atlético , Cafeína , Humanos , Masculino , Fenômenos Biomecânicos , Cafeína/farmacologia , Cinética , Aceleração , Suplementos Nutricionais
2.
Huan Jing Ke Xue ; 45(2): 898-908, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471928

RESUMO

Magnetic phosphorous biochar (MPBC) was prepared from Camellia oleifera shells using phosphoric acid activation and iron co-deposition. The materials were characterized and analyzed through scanning electron microscopy (SEM), X-ray diffractometry (XRD), specific surface area and pore size analysis (BET), Fourier infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). MPBC had a high surface area (1 139.28 m2·g-1) and abundant surface functional groups, and it could achieve fast solid-liquid separation under the action of an external magnetic field. The adsorption behavior and influencing factors of sulfamethoxazole (SMX) in water were investigated. The adsorbent showed excellent adsorption properties for SMX under acidic and neutral conditions, and alkaline conditions and the presence of CO32- had obvious inhibition on adsorption. The adsorption process conformed to the quasi-second-order kinetics and Langmuir model. The adsorption rate was fast, and the maximum adsorption capacity reached 356.49 mg·g-1. The adsorption process was a spontaneous exothermic reaction, and low temperature was beneficial to the adsorption. The adsorption mechanism was mainly the chemisorption of pyrophosphate surface functional groups (C-O-P bond) between the SMX molecule and MPBC and also included hydrogen bonding, π-π electron donor-acceptor (π-πEDA) interaction, and a pore filling effect. The development of MPBC adsorbent provides an effective way for resource utilization of waste Camellia oleifera shells and treatment of sulfamethoxazole wastewater.


Assuntos
Sulfametoxazol , Poluentes Químicos da Água , Sulfametoxazol/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Poluentes Químicos da Água/análise , Carvão Vegetal/química , Fósforo , Cinética , Fenômenos Magnéticos
3.
Bioresour Technol ; 399: 130560, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460563

RESUMO

The potential of hydrolytic enzyme cocktail obtained from designed bacterial consortium WSh-1 comprising Bacillus subtilis CRN 16, Paenibacillus dendritiformis CRN 18, Niallia circulans CRN 24, Serratia marscens CRN 29, and Streptomyces sp. CRN 30, was investigated for maximum saccharification. Activity was further enhanced to 1.01 U/ml from 0.82 U/ml by supplementing growth medium with biotin and cellobiose as a cofactor and inducer. Through kinetic analysis, the enzyme cocktail showed a high wheat straw affinity with Michaelis-Menten constant (Km) of 0.68 µmol/L and a deconstruction rate (Vmax) of 4.5 U/ml/min. The statistical optimization of critical parameters increased saccharification to 89 %. The optimized process in a 5-L lab-scale bioreactor yielded 501 mg/g of reducing sugar from NaOH-pretreated wheat straw. Lastly, genomic insights revealed unique abundant oligosaccharide deconstruction enzymes with the most diverse CAZyme profile. The consortium-mediated enzyme cocktails offer broader versatility with efficiency for the economical and sustainable valorization of lignocellulosic waste.


Assuntos
Consórcios Microbianos , Triticum , Cinética , Carboidratos , Bebidas Alcoólicas , Hidrólise
4.
J Environ Manage ; 355: 120274, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452618

RESUMO

In this study, rooibos tea waste (RTW) incorporated with a binary oxide (BO; Fe2O3-SnO2) has been reported for the first time as a highly efficient adsorbent material for the elimination of Ni(II) ions. The as-synthesised rooibos tea waste-binary oxide (RWBO) composite adsorbent was characterised using miscellaneous techniques such as FTIR, XRD, SEM, EDX, TGA, BET, and XPS. The RWBO was then tested for the removal of Ni(II) in a batch adsorption experiment. The composite adsorbent showed a great removal efficiency of about 99.75% for Ni(II) ions at 45 °C, 180 min agitation time, pH 7, and dosage of 250 mg. The adsorption process was found to be endothermic and spontaneous. Also, the spent adsorbent [RWBO-Ni(II)] was found to be solar light active with a narrow band gap of 1.4 eV. It was further used as a photocatalyst for the photocatalytic abatement of 10 mg/L ciprofloxacin with an extent of degradation of 83% obtained after 150 min. In addition, the extent of mineralisation of the ciprofloxacin by the spent adsorbent as obtained from the TOC data was found to be 64%. Overall, the RWBO composite adsorbent lends itself as an efficient, eco-friendly and promising material for environmental remediation.


Assuntos
Aspalathus , Poluentes Químicos da Água , Níquel , Óxidos , Ciprofloxacina , Chá , Aspalathus/metabolismo , Adsorção , Cinética , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Íons
5.
Carbohydr Res ; 537: 109074, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452719

RESUMO

Two new glycosides, sindosides A-B (1-2), along with 11 previously identified metabolites (3-13), were isolated from an ethanolic extract of the leaves of Sindora siamensis var. maritima. The structures of the purified phytochemicals were elucidated by interpreting their spectroscopic data (IR, NMR, and HRMS). The absolute configuration of compound 1 was established by experimental and calculated ECD spectra. The antimicrobial results revealed that compound 8 selectively inhibited C. albicans fungal with a MIC value of 64 µg/mL, whereas 11 presented a weak inhibition toward E. faecalis, S. aureus, and B. cereus bacterial strains with the same MIC value of 128 µg/mL. Interestingly, compounds 1, 2, 8, 9, and 11 showed α-glucosidase inhibitory activity with IC50 values ranging from 14.42 ± 0.21 to 30.62 ± 0.18 µM, which were more active than the positive control (acarbose, with an IC50 value of 46.78 ± 1.37 µM). Enzyme kinetic analysis revealed that compounds 1, 2, and 11 behaved as uncompetitive inhibitors with Ki values of 8.60 ± 1.04, 5.16 ± 0.73, and 7.17 ± 0.98 µM, respectively.


Assuntos
Anti-Infecciosos , alfa-Glucosidases , alfa-Glucosidases/metabolismo , Cinética , Staphylococcus aureus , Anti-Infecciosos/farmacologia , Extratos Vegetais/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química
6.
J Agric Food Chem ; 72(9): 4939-4946, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38401060

RESUMO

The kinetics of lipid oxidation includes a lag phase followed by an exponential increase in oxidation products, which cause rancidity. Current models focus on the slope of this exponential curve for shelf-life estimation, which still requires the measurement of full oxidation kinetics. In this paper, we analyzed the formation of lipid oxidation products in stripped soybean oil containing different levels of α-tocopherol. The lag phases of lipid hydroperoxides and headspace hexanal formation were found to have a strong positive correlation with the α-tocopherol depletion time. We propose that the kinetics of antioxidant (α-tocopherol) depletion occur during the lag phase and could serve as an early shelf-life indicator. Our results showed that α-tocopherol degradation can be described by Weibull kinetics over a wide range of initial concentrations. Furthermore, we conducted in silico investigations using Monte Carlo simulations to critically evaluate the feasibility and sensitivity of the shelf-life prediction using early antioxidant degradation kinetics. Our results revealed that the shelf life of soybean oil may be accurately predicted as early as 20% of the overall shelf life. This innovative approach provides a more efficient and faster assessment of shelf life, ultimately reducing waste and enhancing product quality.


Assuntos
Antioxidantes , alfa-Tocoferol , Óleo de Soja , Oxirredução , Óleos , Cinética
7.
J Food Sci ; 89(3): 1642-1657, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38317411

RESUMO

ß-Carotene, a precursor of vitamin A, can alleviate the deficiency of this vitamin prevalent worldwide. Earlier research studies have addressed the extraction of ß-carotene at relatively low temperatures (up to 70°C) due to its perceived instability at higher temperatures, as a result of which extraction rates recorded are relatively low. This study models the net rate of ß-carotene extraction by considering both extraction and degradation kinetics. The model developed, which accounts for degradation occurring in solid and extract phases, has been experimentally validated for the extraction of ß-carotene from freeze-dried carrot powder into sunflower oil over a range of temperatures 90-150°C. This study also gives insights into the application of sunflower oil as a carrier for ß-carotene during cooking and food processing, by monitoring and modeling the thermal degradation and isomerization of ß-carotene at temperatures up to 220°C. The modeling of extraction kinetics shows that it is possible to achieve viable extraction rates by employing temperatures in the range (90-150°C) for relatively short times (<5 min). The degradation kinetics shows that almost 75% of the ß-carotene can survive heating at 180°C for 10 min-indicating the possibility of using ß-carotene enriched edible oils for frying. This study also reports on the formation of three isomers of ß-carotene identified using HPLC: trans-, 9-cis, and 13-cis. The reaction network model developed in this study was able to account for the transient variation of the concentration of all three isomers. PRACTICAL APPLICATION: ß-Carotene is a precursor of vitamin A and its consumption can potentially alleviate the deficiency of this vitamin prevalent worldwide. This study validates a model for the extraction of ß-carotene in sunflower oil, which takes into account extraction as well as degradation occurring during extraction, so that a rational method is available for the design of efficient extractors for this purpose. This paper also establishes the thermal stability of ß-carotene under frying conditions by quantifying its thermal degradation as well as isomerization.


Assuntos
Daucus carota , beta Caroteno , beta Caroteno/metabolismo , Vitamina A , Óleo de Girassol , Pós , Temperatura , Vitaminas , Cinética
8.
J Chromatogr A ; 1719: 464712, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38377662

RESUMO

A drastic increase in demand for electric vehicles and energy storage systems increases lithium (Li) need as a critical metal for the 21st century. Lithium manganese oxides stand out among inorganic adsorbents because of their high capacity, chemical stability, selectivity, and affordability for lithium recovery from aqueous media. This study investigates using hydrometallurgically synthesized lithium manganese oxide (Li1.6Mn1.6O4) in granular form coated with cross-linked chitosan for lithium recovery from water. Characterization methods such as SEM, FTIR, XRD, and BET reveal the successful synthesis of the composite adsorbent. Granular cross-linked chitosan-coated and delithiated lithium manganese oxide (CTS/HMO) adsorbent demonstrated optimal removal efficiency of 86 % at pH 12 with 4 g/L of adsorbent dosage. The Langmuir isotherm at 25 °C, which showed monolayer adsorption with a maximum capacity of 4.94 mg/g, a better fit for the adsorption behavior of CTS/HMO. Adsorption was endothermic and thermodynamically spontaneous. Lithium adsorption followed the pseudo-first-order kinetic model.


Assuntos
Óxido de Alumínio , Quitosana , Óxido de Magnésio , Poluentes Químicos da Água , Água , Manganês , Lítio , Quitosana/química , Adsorção , Óxidos/química , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
9.
Int J Biol Macromol ; 261(Pt 2): 129882, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309405

RESUMO

This research investigates the application of an innovative bio-nanocomposite, Fenugreek seed mucilage/silicon carbide (FSM/SiC), as an exceptionally effective adsorbent for eliminating cadmium ions from aqueous solutions. Optimization of fenugreek mucilage extraction involved ultrasonic methods, establishing ideal conditions with a solid-to-solvent ratio of 1:55, 50 °C temperature, 37 kHz frequency, 100 % power, and 30 min processing time. Comprehensive characterization through FTIR spectroscopy, XRD, imaging, DLS, and SEM confirmed the preservation of crucial adsorption-related characteristics. Enhanced adsorption efficiency was achieved by systematically adjusting pH, temperature, adsorbent concentration, pollutant concentration, and contact time, identifying optimal conditions at pH 6, 0.03 g adsorbent dosage, 35 min contact time, and 30 mg/L initial cadmium concentration at 30 °C. Adsorption kinetics followed a pseudo-second-order model, while the Langmuir isotherm fit suggested monolayered adsorption. Thermodynamic analysis indicated exothermic and spontaneous Cd2+ ion adsorption onto FSM/SiC. Remarkably, FSM/SiC demonstrated exceptional regeneration potential, positioning it as a promising solution for water decontamination and environmental remediation. This research showcases FSM/SiC's potential with a maximum adsorption capacity of 41.6 mg/g for cadmium ions, highlighting its significance in addressing cadmium contamination.


Assuntos
Nanocompostos , Extratos Vegetais , Trigonella , Poluentes Químicos da Água , Cádmio/química , Termodinâmica , Água/química , Íons , Adsorção , Cinética , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química
10.
Int J Biol Macromol ; 261(Pt 2): 129962, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316322

RESUMO

In this work, novel monoclinic tungsten oxide (WO3)-encapsulated phosphate-rich porous sodium alginate (PASA) microspherical hydrogel beads were prepared for efficient U(VI) capture. These macroporous and hollow beads were systematically characterized through XRD, FTIR, EDX-mapping, and SEM-EDS techniques. The O and P atoms in the PO and monoclinic WO3 offered inner-spherical complexation with U(VI). The in situ growth of WO3 played a significant role inside the phosphate-rich biopolymeric network to improve its chemical stability, specific surface area, adsorption capacity, and sorption rate. The phytic acid (PA) served for heteroatom doping and crosslinking. The encapsulated WO3 mass ratio was optimized in different composites, and WO3/PASA3 (the microspherical beads with a mass ratio of 30.0 % w/w) exhibited remarkable maximum sorption capacity qm (336.42 mg/g) computed through the best-fit Langmuir model (R2 ≈ 0.99) and rapid sorption equilibrium, teq (150 min). The isothermal sorption studies were conducted at different temperatures (298, 303, and 308 K) and thermodynamic parameters concluded that the process of U(VI) sorption using WO3/PASA3 is endothermic and feasible having ΔHo (8.19 kJ/mol), ΔGo (-20.75, -21.38, and - 21.86 kJ/mol) and proceeds with a minute increase in randomness ΔSo (0.09 kJ/mol.K). Tungsten oxide (WO3)-encapsulated phosphate-rich porous microspherical beads could be promising material for uranium removal.


Assuntos
Alginatos , Óxidos , Tungstênio , Urânio , Alginatos/química , Adsorção , Fosfatos , Porosidade , Termodinâmica , Cinética , Urânio/química , Concentração de Íons de Hidrogênio
11.
Int J Biol Macromol ; 261(Pt 2): 129900, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316329

RESUMO

The presence of potentially toxic elements and compounds poses threats to the quality and safety of fruit juices. Among these, Hg(II) is considered as one of the most poisonous heavy metals to human health. Traditional chitosan-based and selenide-based adsorbents face challenges such as poor adsorption capacity and inconvenient separation in juice applications. In this study, we prepared nano­selenium functionalized chitosan gel beads (nanoSe@CBs) and illustrated the synergistic promotions between chitosan and nanoSe in removing Hg(II) from apple juice. The preparation conditions, adsorption behaviors, and adsorption mechanism of nanoSe@CBs were systematically investigated. The results revealed that the adsorption process was primarily controlled by chemical adsorption. At the 0.1 % dosage, the adsorbent exhibited high uptake, and the maximum adsorption capacity from the Langmuir isotherm model could reach 376.5 mg/g at room temperature. The adsorbent maintained high adsorption efficiency (> 90 %) across a wide range of Hg(II) concentrations (0.01 to 10 mg/L) and was unaffected by organic acids present in apple juice. Additionally, nanoSe@CBs showed negligible effects on the quality of apple juice. Overall, nanoSe@CBs open up possibilities to be used as a safe, low-cost and highly-efficient adsorbent for the removal of Hg(II) from juices and other liquid foods.


Assuntos
Quitosana , Malus , Mercúrio , Selênio , Poluentes Químicos da Água , Humanos , Sucos de Frutas e Vegetais , Malus/química , Quitosana/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
12.
Environ Pollut ; 345: 123510, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38325506

RESUMO

High levels of phosphorus released into the environment can cause eutrophication issues in wastewater, therefore discharge concentrations of such element are regulated in many countries. This study addresses the pressing need for effective phosphorus removal methods by developing a novel La2(CO3)3 and MnFe2O4 loaded biochar composite (LMB). A remarkable adsorption capacity towards the three forms of phosphorus from wastewater, including phosphate, phosphite, and etidronic acid monohydrate (as a representative of organic phosphorus), was exhibited by LMB (88.20, 16.35, and 15.95 mg g-1, respectively). The high saturation magnetization value (50.17 emu g-1) highlighted the easy separability and recyclability of the adsorbent. The adsorption process was well described by the Langmuir isotherm model and the pseudo-second-order kinetic model, which mainly involved chemisorption. Characterization results confirm the effective loading of La2(CO3)3 with ligand exchange and electrostatic attraction identified as the primary mechanisms. Importantly, the LMB demonstrated exceptional selectivity for phosphorus in wastewater samples containing various substances, exhibiting minimal interference from competing ions (Cl-, NO3-, SO42-, and CO32-). These findings enhance the understanding of LMB's application in efficient wastewater phosphorus removal. Holding significant promise in wastewater remediation, the LMB acts as an effective adsorbent, contributing substantially to the prevention and control of various types of phosphorus pollutants, thereby mitigating wastewater eutrophication.


Assuntos
Carvão Vegetal , Fósforo , Poluentes Químicos da Água , Fósforo/química , Águas Residuárias , Fosfatos , Adsorção , Cinética , Fenômenos Magnéticos , Poluentes Químicos da Água/análise
13.
Environ Sci Pollut Res Int ; 31(13): 19753-19763, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38363504

RESUMO

Three waste plant oils (olive oil, coconut oil, and soybean oil) were utilized as monomer crosslinking agents to synthesize polysulfides by inverse vulcanization with elemental sulfur, for mercury removal from wastewater. NMR analysis showed that 92.1% of the olefins participated in the inverse vulcanization reaction, indicating that the quantity of unsaturated olefins in plant oil mainly affects the ring-opening ratio of sulfur for the formation of sulfur-based polymers. The experimental results showed that olive oil polysulfide (S-r-olive) achieved 100% Hg2+ removal within 2 h at a pH of 6. The S-r-olive, S-r-soybean, and S-r-coconut exhibited adsorption capacities of 130.23, 42.72, and 28.08 mg/g, respectively. The kinetic and adsorption isotherm illustrated that the Hg2+ adsorption by polysulfides conformed to the pseudo-second-order and Freundlich models, showing that the reaction rate constant of S-r-olive is approximately 14 times and 4.6 times greater than that of S-r-soybean and S-r-coconut, respectively. The adsorption mechanism is concluded that Hg2+ first enters the suspended S-r-olive by physical adsorption, then combined with sulfur to form HgS by chemical action and fixed in the S-r-olive adsorbent. This study demonstrates that utilizing waste plant oils as monomer crosslinking agents to synthesize adsorbents for Hg2+ removal is feasible and effective.


Assuntos
Mercúrio , Olea , Sulfetos , Poluentes Químicos da Água , Águas Residuárias , Mercúrio/análise , Óleos de Plantas , Azeite de Oliva , Adsorção , Enxofre , Poluentes Químicos da Água/análise , Cinética
14.
Chemosphere ; 352: 141398, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342147

RESUMO

Hydroxyapatite has a high affinity to uranium, and element doping can effectively improve its adsorption performance. In this study, magnesia-silica-fluoride co-doped hydroxyapatite composite was prepared by hydrothermal method, and the effect of single-phase and multiphase doping on the structure and properties of the composites was investigated. The results showed that the specific surface area of Mg-Si-F-nHA composites increased by 63.01% after doping. Comparing with nHA, U(VI) adsorption capacity of Si-nHA, Mg-Si-nHA and Mg-Si-F-nHA composites increased by 13.01%, 17.39% and 22.03%, respectively. The adsorption capacity of Mg-Si-F-nHA composite reached 1286.76 mg/g. Adsorbent dosage and pH obviously affected U(VI) adsorption, and the experimental data can be fitted well by PSO and Sips models. The physicochemical characterization before and after adsorption suggested that complexation, ion exchange and precipitation participated in uranium adsorption. In conclusion, different elements doping can effectively improve the uranium adsorption properties of hydroxyapatite composites.


Assuntos
Fluoretos , Urânio , Dióxido de Silício , Óxido de Magnésio , Urânio/análise , Adsorção , Durapatita/química , Concentração de Íons de Hidrogênio , Cinética
15.
Food Res Int ; 178: 113878, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38309896

RESUMO

Coffee processing generates large amounts of residues of which a portion still has bioactive properties due to their richness in phenolic compounds. This study aimed to obtain a coffee husks extract (CHE) and to encapsulate it (ECHE) with polyvinylpyrrolidone using a one-step procedure of solid dispersion. The extraction and encapsulation yields were 9.1% and 92%, respectively. Thermal analyses revealed that the encapsulation increased the thermal stability of CHE and dynamic light scattering analyses showed a bimodal distribution of size with 81% of the ECHE particles measuring approximately 711 nm. Trigonelline and caffeine were the main alkaloids and quercetin the main phenolic compound in CHE, and the encapsulation tripled quercetin extraction. The total phenolics content and the antioxidant activity of ECHE, assayed with three different procedures, were higher than those of CHE. The antioxidant activity and the bioaccessibility of the phenolic compounds of ECHE were also higher than those of CHE following simulated gastrointestinal digestion (SGID). Both CHE and ECHE were not toxic against Alliumcepa cells and showed similar capacities for inhibiting the pancreatic α-amylase in vitro. After SGID, however, ECHE became a 1.9-times stronger inhibitor of the α-amylase activity in vitro (IC50 = 8.5 mg/mL) when compared to CHE. Kinetic analysis revealed a non-competitive mechanism of inhibition and in silico docking simulation suggests that quercetin could be contributing significantly to the inhibitory action of both ECHE and CHE. In addition, ECHE (400 mg/kg) was able to delay by 50% the increases of blood glucose in vivo after oral administration of starch to rats. This finding shows that ECHE may be a candidate ingredient in dietary supplements used as an adjuvant for the treatment of diabetes.


Assuntos
Antioxidantes , Coffea , Ratos , Animais , Antioxidantes/análise , Quercetina , Povidona , Coffea/química , Cinética
16.
Environ Sci Pollut Res Int ; 31(13): 19974-19985, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368300

RESUMO

Using organic waste and residue streams to be turned into valuable and greener materials for various applications has proven an efficient and suitable strategy. In this work, two green materials (nanosponges and a polymer) were synthesized using potato peels and applied for the first time to adsorb and recover Neodymium (Nd3+) from aqueous solutions. The recovery of Nd3+ that belongs to the rare earth elements has attracted important interest due to its/their importance in several industrial and technological applications. The fine potato peel waste (FPPW) polymer presented an irregular shape and porous surface. At the same time, the ß-cyclodextrin (ß-CD) nanosponges had uniform distribution with regular and smooth shapes. ß-CD nanosponges exhibited a much higher total carboxyl content (4.02 mmol g-1) than FPPW (2.50 mmol g-1), which could impact the Nd3+ adsorption performance because carboxyl groups can interact with cations. The adsorption capacity increased with the increase of the pH, reaching its maximum at pHs 6-7 for ß-CD nanosponges and 4-7 for FPPW polymer. The kinetic and equilibrium data were well-fitted by General order and Liu models. ß-CD nanosponges attained adsorption capacity near 100 mg Nd per gram of adsorbent. Thermodynamic and statistical physical results corroborated that the adsorption mechanism was due to electrostatic interaction/complexation and that the carboxyl groups were important in the interactions. ß-CD nanosponges (three cycles of use) were more effective than FPPW (one cycle of use) in the regeneration. Finally, ß-CD nanosponges could be considered an eco-friendly adsorbent to recover Nd3+ from aqueous matrices.


Assuntos
Solanum tuberosum , beta-Ciclodextrinas , Neodímio , Adsorção , Polímeros , beta-Ciclodextrinas/química , Água/química , Física , Cinética
17.
J Ethnopharmacol ; 319(Pt 3): 117368, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38380570

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Nyctanthes arbor-tristis Linn. has been used by Ayruvedic physicians for the cure of different diseases including ulcers, gastric and inflammatory diseases. AIM OF THE STUDY: To isolate and identify compounds from this source and investigate their therapeutic potential for the treatment of gastric ulcer and related disorders. MATERIAL AND METHODS: The ethanol extract of fresh aerial parts of N. arbor-tristis was used in the present studies which was subjected to a bio-assay guided fractionation followed by chromatographic separations. The structures of pure compounds were elucidated using various spectroscopic techniques. The inhibition of urease enzyme was evaluated by weatherburn indophenol method. Molecular docking studies were determined by using Molecular Operating Environment (MOE) version 2020.0901 version. The intracellular ROS production from phagocytes was determined by chemiluminescence assay and NO generation was detected by Griess method. The proinflammatory cytokine TNF-α was quantified by ELISA. Cytotoxic activity was assessed by MTT assay. RESULTS: One previously undescribed iridoid glycoside arborside F (1) and four known iridoid glycosides arborside A (2), arborside C (3), loganin (4) and 7-O-trans-cinnamoyl-6ß-hydroxyloganin (5) were isolated and characterized in the present studies and their urease inhibitory activity was determined. Among these, 2 and 5 showed strong urease inhibition (IC50 = 12.1 ± 1.74 and 14.1 ± 0.59 µM respectively) (standard acetohydroxamic acid IC50 = 20.3 ± 0.42 µM), whereas rest of compounds showed moderate to low inhibition. Kinetic studies revealed that compounds 2 and 5 possess competitive type of inhibition. Molecular docking showed polar and non-polar interactions of compounds 2 and 5 with urease enzyme residues. Compounds 2 and 3 showed inhibition of ROS from whole blood (IC50 = 1.6 ± 0.3 and 2.5 ± 0.09 µg/mL respectively) and PMNs (IC50 = 1.5 ± 0.03 and 1.4 ± 0.0 µg/mL respectively). Compound 2 significantly inhibited nitric oxide and proinflammatory cytokine TNF-α (IC50 = 18.2 ± 3.0 and 73.8 ± 6.6 µg/mL respectively). Compounds 1, 4 and 5 were inactive on ROS. All isolated compounds were non-toxic on normal mouse fibroblasts (NIH-3T3) cells. CONCLUSIONS: The ethno pharmacological repute of N. arbor-tristis in treating gastric and anti-inflammatory ailments is supported by present studies which resulted in isolation of a potent urease inhibitory and anti-inflammatory agent arborside A (2) a potential anti-ulcer and anti-inflammatory drug lead.


Assuntos
Extratos Vegetais , Urease , Camundongos , Animais , Extratos Vegetais/uso terapêutico , Glicosídeos Iridoides/farmacologia , Cinética , Simulação de Acoplamento Molecular , Espécies Reativas de Oxigênio , Fator de Necrose Tumoral alfa , Anti-Inflamatórios/farmacologia
18.
Environ Sci Pollut Res Int ; 31(11): 16554-16570, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38319420

RESUMO

The directed construction of productive adsorbents is essential to avoid damaging human health from the harmful radioactive and toxic U(VI)-containing wastewater. Herein, a sort of Zr-based metal organic framework (MOF) called PCN-222 was synthesized and oxime functionalized based on directed molecular structure design to synthesize an efficient adsorbent with antimicrobial activity, named PCN-222-OM, for recovering U(VI) from wastewater. PCN-222-OM unfolded splendid adsorption capacity (403.4 mg·g-1) at pH = 6.0 because of abundant holey structure and mighty chelation for oxime groups with U(VI) ions. PCN-222-OM also exhibited outstanding selectivity and reusability during the adsorption. The XPS spectra authenticated the -NH and oxime groups which revealed a momentous function. Concurrently, PCN-222-OM also possessed good antimicrobial activity, antibiofouling activity, and environmental safety; adequately decreased detrimental repercussions about bacteria and Halamphora on adsorption capacity; and met non-toxic and non-hazardous requirements for the application. The splendid antimicrobial activity and antibiofouling activity perhaps arose from the Zr6(µ3-O)4(µ3-OH)4(H2O)4(OH)4 clusters and rich functional groups within PCN-222-OM. Originally proposed PCN-222-OM was one potentially propitious material to recover U(VI) in wastewater on account of outstanding adsorption capacity, antimicrobial activity, antibiofouling activity, and environmental safety, meanwhile providing a newfangled conception on the construction of peculiar efficient adsorbent.


Assuntos
Anti-Infecciosos , Urânio , Humanos , Águas Residuárias , Urânio/análise , Oximas , Estrutura Molecular , Adsorção , Cinética
19.
Environ Sci Pollut Res Int ; 31(11): 16940-16957, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38326685

RESUMO

The applications of polysulfides derived from natural plant oil and sulfur via the inverse vulcanization in the removal of heavy metals from aqueous solutions suffered from their low porosity and scarce surface functionality because of their hydrophobic surfaces and bulk characteristics. In this study, polysulfides from sulfur and palm oil (PSPs) with significantly enhanced porosity (13.7-24.1 m2/g) and surface oxygen-containing functional groups (6.9-8.6 wt.%) were synthesized with the optimization of process conditions including reaction time, temperature, and mass ratios of sulfur/palm oil/NaCl/sodium citrate. PSPs were applied as sorbents to remove heavy metals present in aqueous solutions. The integration of porosity and oxygen modification allowed a fast kinetic (4.0 h) and enhanced maximum sorption capacities for Pb(II) (218.5 mg/g), Cu(II) (74.8 mg/g), and Cr(III) (68.4 mg/g) at pH 5.0 and T 298 K comparing with polysulfides made without NaCl/sodium citrate. The sorption behaviors of Pb(II), Cu(II), and Cr(III) on PSPs were highly dependent on the solution pH values and ionic strength. The sorption presented excellent anti-interference capability for the coexisting cations and anions. The sorption processes were endothermic and spontaneous. This work would guide the preparation of porous polysulfides with surface modification as efficient sorbents to remediate heavy metals from aqueous solutions.


Assuntos
Metais Pesados , Sulfetos , Poluentes Químicos da Água , Porosidade , Cloreto de Sódio , Chumbo , Óleo de Palmeira , Citrato de Sódio , Metais Pesados/química , Água , Enxofre , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/química
20.
J Environ Radioact ; 273: 107398, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38346378

RESUMO

Enzymatically catalyzed reduction of metals by bacteria has potential application value to uranium-mine wastewater. However, its practical implementation has long been restricted by its intrinsic drawbacks such as low efficiency and long treatment-time. This study aims to explore the effect of electrodes on U (VI) removal efficiency by a purified indigenous bacteria isolated from a uranium mining waste pile in China. The effects of current intensity, pH, initial U (Ⅵ) concentration, initial dosage of bacteria and contact time on U (Ⅵ) removal efficiency were investigated via static experiments. The results show that U(VI) removal rate was stabilized above 90% and the contact time sharply shortened within 1 h when utilized nickel-graphite electrode as an electron donor. Over the treatment ranges investigated maximum removal of U (Ⅵ) was 96.04% when the direct current was 10 mA, pH was 5, initial U (Ⅵ) concentration was 10 mg/L, and dosage of Leifsonia sp. was 0.25 g/L. In addition, it is demonstrated that U (VI) adsorption by Leifsonia sp. is mainly chemisorption and/or reduction as the quasi-secondary kinetics is more suitable for fitting the process. FTIR results indicated that amino, amide, aldehyde and phosphate -containing groups played a role in the immobilization of U (VI) more or less. SEM and EDS measurements revealed that U appeared to be more obviously aggregated on the surface of cells. A plausible explanation for this, supported by XPS, is that U (VI) was partially reduced to U (IV) by direct current then precipitated on the cells surface. These observations reveal that Nickel-graphite electrode exhibited good electro-chemical properties and synergistic capacity with Leifsonia sp. which potentially provides a new avenue for uranium enhanced removal/immobilization by indigenous bacteria.


Assuntos
Grafite , Monitoramento de Radiação , Urânio , Níquel , Urânio/análise , Elétrons , Bactérias , Eletrodos , Adsorção , Cinética
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