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1.
J Chromatogr A ; 1722: 464896, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38631224

RESUMEN

In this study, a novel magnetic bead-based ligand fishing method was developed for rapid discovery of monoterpene indoles as monoamine oxidase A inhibitors from natural products. In order to improve the screening efficiency, two different magnetic beads, i.e. amine and carboxyl terminated magnetic beads, were comprehensively compared in terms of their ability to immobilize monoamine oxidase A (MAOA), biocatalytic activity and specific adsorption rates for affinity ligands. Carboxyl terminated magnetic beads performed better for MAOA immobilization and demonstrated superior performance in ligand fishing. The MAOA immobilized magnetic beads were applied to screen novel monoamine oxidase inhibitors in an alkaloid-rich plant, Hunteria zeylanica. Twelve MAOA affinity ligands were screened out, and ten of them were identified as monoterpene indole alkaloids by HPLC-Obitrap-MS/MS. Among them, six ligands, namely geissoschizol, vobasinol, yohimbol, dihydrocorynanthenol, eburnamine and (+)-isoeburnamine which exhibited inhibitory activity against MAOA with low IC50 values. To further explore their inhibitory mechanism, enzyme kinetic analysis and molecular docking studies were conducted.


Asunto(s)
Simulación del Acoplamiento Molecular , Inhibidores de la Monoaminooxidasa , Monoaminooxidasa , Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/farmacología , Inhibidores de la Monoaminooxidasa/aislamiento & purificación , Monoaminooxidasa/metabolismo , Monoaminooxidasa/química , Ligandos , Indoles/química , Monoterpenos/química , Monoterpenos/aislamiento & purificación , Cinética , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Enzimas Inmovilizadas/antagonistas & inhibidores , Humanos , Extractos Vegetales/química
2.
Sci Rep ; 14(1): 8406, 2024 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600150

RESUMEN

The aim of this work was to synthesize a green nanoparticle SnCuO@FeO nanocomposite core-shell to break oily water emulsions during petroleum-enhancing production processes as an alternative to chemical and physical processes. In this study, eight bacterial isolates (MHB1-MHB8) have been isolated from tree leaves, giant reeds, and soil samples. The investigation involved testing bacterial isolates for their ability to make FeO nanoparticles and choosing the best producers. The selected isolate (MHB5) was identified by amplification and sequencing of the 16S rRNA gene as Bacillus paramycoides strain OQ878685. MHB5 produced the FeO nanoparticles with the smallest particle size (78.7 nm) using DLS. XRD, FTIR, and TEM were used to characterize the biosynthesized nanoparticles. The jar experiment used SnCuO@FeO with different ratios of Sn to CuO (1:1, 2:1, and 3:1) to study the effect of oil concentration, retention time, and temperature. The most effective performance was observed with a 1:1 ratio of Sn to CuO, achieving an 85% separation efficiency at a concentration of 5 mg/L, for a duration of 5 min, and at a temperature of 373 K. Analysis using kinetic models indicates that the adsorption process can be accurately described by both the pseudo-first-order and pseudo-second-order models. This suggests that the adsorption mechanism likely involves a combination of film diffusion and intraparticle diffusion. Regarding the adsorption isotherm, the Langmuir model provides a strong fit for the data, while the D-R model indicates that physical interactions primarily govern the adsorption mechanism. Thermodynamic analysis reveals a ∆H value of 18.62 kJ/mol, indicating an exothermic adsorption process. This suggests that the adsorption is a favorable process, as energy is released during the process. Finally, the synthesized green SnCuO@FeO nanocomposite has potential for use in advanced applications in the oil and gas industry to help the industry meet regulatory compliance, lower operation costs, reduce environmental impact, and enhance production efficiency.


Asunto(s)
Nanocompuestos , Petróleo , Contaminantes Químicos del Agua , Emulsiones , ARN Ribosómico 16S , Termodinámica , Agua/química , Adsorción , Cinética , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno
3.
PLoS One ; 19(4): e0301986, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38626158

RESUMEN

The production of sludge-based biochar to recover phosphorus (P) from wastewater and reuse the recovered phosphorus as agricultural fertilizer is a preferred process. This article mainly studied the removal of phosphate (PO4-P) from aqueous solution by synthesizing sludge-based biochar (MgSBC-0.1) from anaerobic fermentation sludge treated with magnesium (Mg)-loading-modification, and compared it with unmodified sludge-based biochar (SBC). The physicochemical properties, adsorption efficiency, and adsorption mechanism of MgSBC-0.1 were studied. The results showed that the surface area of MgSBC-0.1 synthesized increased by 5.57 times. The material surface contained MgO, Mg(OH)2, and CaO nanoparticles. MgSBC-0.1 can effectively remove phosphate in the initial solution pH range of 3.00-7.00, with a fitted maximum phosphorus adsorption capacity of 379.52 mg·g-1. The adsorption conforms to the pseudo second-order kinetics model and Langmuir isotherm adsorption curve. The characterization of the adsorbed composite material revealed the contribution of phosphorus crystal deposition and electrostatic attraction to phosphorus absorption.


Asunto(s)
Fosfatos , Contaminantes Químicos del Agua , Fosfatos/química , Magnesio , Aguas del Alcantarillado , Adsorción , Carbón Orgánico , Fósforo/química , Cinética , Contaminantes Químicos del Agua/análisis
4.
Photodermatol Photoimmunol Photomed ; 40(3): e12964, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38616405

RESUMEN

INTRODUCTION: Pityriasis lichenoides chronica is the chronic end of the spectrum of pityriasis lichenoides which have several forms of papulosuamous conditions. Several treatments obtained complete clearance of the condition including phototherapy and specifically narrow band ultraviolet B. The Excimer light 308 is a monochromatic light that acts within the ultraviolet B wavelength and used as a targeted phototherapy in several skin conditions. METHODS: Thirty-four patients with histopathologically diagnosed pityriasis lichenoides chronica underwent treatment with biweekly sessions of excimer light 308 nm. Treatment continued until complete clearance was obtained or to a maximum of 48 sessions (24 weeks). RESULTS: Thirty-one patients obtained complete clearance with no recurrence till the end of the study period, two patients had partial response and only one patient showed poor response to treatment. CONCLUSION: Excimer light can be a safe and effective treatment of pityriasis lichinoides chronica in different ages and genders.


Asunto(s)
Pitiriasis Liquenoide , Humanos , Femenino , Masculino , Pitiriasis Liquenoide/radioterapia , Fototerapia , Cinética
5.
Environ Sci Pollut Res Int ; 31(20): 29264-29279, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38573576

RESUMEN

Guided by efficient utilization of natural plant oil and sulfur as low-cost sorbents, it is desired to tailor the porosity and composition of polysulfides to achieve their optimal applications in the management of aquatic heavy metal pollution. In this study, polysulfides derived from soybean oil and sulfur (PSSs) with improved porosity (10.2-22.9 m2/g) and surface oxygen content (3.1-7.0 wt.%) were prepared with respect to reaction time of 60 min, reaction temperature of 170 °C, and mass ratios of sulfur/soybean oil/NaCl/sodium citrate of 1:1:3:2. The sorption behaviors of PSSs under various hydrochemical conditions such as contact time, pH, ionic strength, coexisting cations and anions, temperature were systematically investigated. PSSs presented a fast sorption kinetic (5.0 h) and obviously improved maximum sorption capacities for Pb(II) (180.5 mg/g), Cu(II) (49.4 mg/g), and Cr(III) (37.0 mg/g) at pH 5.0 and T 298 K, in comparison with polymers made without NaCl/sodium citrate. This study provided a valuable reference for the facile preparation of functional polysulfides as well as a meaningful option for the removal of aquatic heavy metals.


Asunto(s)
Cobre , Plomo , Metales Pesados , Aceite de Soja , Sulfuros , Contaminantes Químicos del Agua , Adsorción , Plomo/química , Aceite de Soja/química , Cobre/química , Sulfuros/química , Porosidad , Contaminantes Químicos del Agua/química , Metales Pesados/química , Cromo/química , Cinética , Concentración de Iones de Hidrógeno
6.
J Pharm Biomed Anal ; 244: 116125, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38554553

RESUMEN

As a pivotal enzyme that regulates dephosphorylation in cell activities and participates in the insulin signaling pathway, protein tyrosine phosphatase 1B (PTP1B) is considered to be an important target for the therapy of diabetes. In this work, a rapid and efficient inhibitor screening method of PTP1B was established based on capillary electrophoresis (CE), and used for screening and evaluating the inhibition effect of Traditional Chinese Medicine on PTP1B. Response Surface Methodology was used for optimizing the conditions of analysis. After method validation, the enzyme kinetic study and inhibition test were performed. As a result, the IC50 of PTP1B inhibitors Ⅳ and ⅩⅧ were consistent with reported values measured by a conventional method. It was found that the extracts of Astragalus membranaceus (Fisch) Bunge and Morus alba L. showed prominent inhibition on the activity of PTP1B, which were stronger than the positive controls. Meanwhile, on top of the excellent advantages of CE, the whole analysis time is less than 2 min. Thus, the results demonstrated that a fast and efficient screening method was successfully developed. This method could be a powerful tool for screening inhibitors from complex systems. It can also provide an effective basis for lead compound development in drug discovery.


Asunto(s)
Medicamentos Herbarios Chinos , Electroforesis Capilar , Hipoglucemiantes , Medicina Tradicional China , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Electroforesis Capilar/métodos , Hipoglucemiantes/farmacología , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Medicina Tradicional China/métodos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/análisis , Morus/química , Astragalus propinquus , Humanos , Cinética
7.
J Environ Manage ; 355: 120274, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38452618

RESUMEN

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.


Asunto(s)
Aspalathus , Contaminantes Químicos del Agua , Níquel , Óxidos , Ciprofloxacina , , Aspalathus/metabolismo , Adsorción , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Iones
8.
Molecules ; 29(6)2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38542970

RESUMEN

Currently, little is known about the characteristics of polyphenol oxidase from wheat bran, which is closely linked to the browning of wheat product. The wheat PPO was purified by ammonium sulfate precipitation, DEAE-Sepharose ion-exchange column, and Superdex G-75 chromatography column. Purified wheat PPO activity was 11.05-fold higher, its specific activity was 1365.12 U/mg, and its yield was 8.46%. SDS-PAGE showed that the molecular weight of wheat PPO was approximately 21 kDa. Its optimal pH and temperature were 6.5 and 35 °C for catechol as substrate, respectively. Twelve phenolic substrates from wheat and green tea were used for analyzing the substrate specificity. Wheat PPO showed the highest affinity to catechol due to its maximum Vmax (517.55 U·mL-1·min-1) and low Km (6.36 mM) values. Docking analysis revealed strong affinities between catechol, gallic acid, EGCG, and EC with binding energies of -5.28 kcal/mol, -4.65 kcal/mol, -4.21 kcal/mol, and -5.62 kcal/mol, respectively, for PPO. Sodium sulfite, ascorbic acid, and sodium bisulfite dramatically inhibited wheat PPO activity. Cu2+ and Ca2+ at 10 mM were considered potent activators and inhibitors for wheat PPO, respectively. This report provides a theoretical basis for controlling the enzymatic browning of wheat products fortified with green tea.


Asunto(s)
Catecol Oxidasa , Fibras de la Dieta , Catecol Oxidasa/química , Fibras de la Dieta/análisis , Concentración de Iones de Hidrógeno , Cinética , Proteínas de Plantas/metabolismo , Catecoles/análisis , Especificidad por Sustrato ,
9.
Carbohydr Res ; 537: 109074, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38452719

RESUMEN

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.


Asunto(s)
Antiinfecciosos , alfa-Glucosidasas , alfa-Glucosidasas/metabolismo , Cinética , Staphylococcus aureus , Antiinfecciosos/farmacología , Extractos Vegetales/química , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química
10.
Environ Sci Pollut Res Int ; 31(17): 26112-26122, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38492141

RESUMEN

In this study, a bacterial strain Chryseobacterium bernardetii WK-3 was isolated from the rhizosphere soil of a uranium tailings in Southern China. It can efficiently adsorb hexavalent uranium with an adsorption ratio of 92.3%. The influence of different environmental conditions on the adsorption ratio of Chryseobacterium bernardetii strain WK-3 was investigated, and the adsorption mechanism was preliminarily discussed by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). The results showed that the optimal adsorption conditions for U(VI) by Chryseobacterium bernardetii strain WK-3 were pH = 5, temperature 30 ℃, NaCl concentration 1%, and inoculation volume 10%. When the initial concentration of U was 50 ~ 150 mg/L, the adsorption capacity of Chryseobacterium bernardetii strain WK-3 to U(VI) reached the maximum and maintained the equilibrium at 44 h. SEM-EDS results showed that phosphorus in cells participates in the interaction of uranyl ions, which may indicate that phosphate was produced during cell metabolism and was further combined to form U(VI)-phosphate minerals. In summary, Chryseobacterium bernardetii strain WK-3 would be a promising alternative for environmental uranium contamination remediation.


Asunto(s)
Chryseobacterium , Uranio , Uranio/análisis , Adsorción , Suelo , Fosfatos , Cinética , Concentración de Iones de Hidrógeno
11.
J Ethnopharmacol ; 328: 118116, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38548118

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Aristolochic acids (AAs) are naturally occurring nitro phenanthrene carboxylic acids primarily found in plants of the Aristolochiaceae family. Aristolochic acid D (AAD) is a major constituent in the roots and rhizomes of the Chinese herb Xixin (the roots and rhizomes of Asarum heterotropoides F. Schmidt), which is a key material for preparing a suite of marketed Chinese medicines. Structurally, AAD is nearly identical to the nephrotoxic aristolochic acid I (AAI), with an additional phenolic group at the C-6 site. Although the nephrotoxicity and metabolic pathways of AAI have been well-investigated, the metabolic pathway(s) of AAD in humans and the influence of AAD metabolism on its nephrotoxicity has not been investigated yet. AIM OF THE STUDY: To identify the major metabolites of AAD in human tissues and to characterize AAD O-glucuronidation kinetics in different enzyme sources, as well as to explore the influence of AAD O-glucuronidation on its nephrotoxicity. MATERIALS AND METHODS: The O-glucuronide of AAD was biosynthesized and its chemical structure was fully characterized by both 1H-NMR and 13C-NMR. Reaction phenotyping assays, chemical inhibition assays, and enzyme kinetics analyses were conducted to assess the crucial enzymes involved in AAD O-glucuronidation in humans. Docking simulations were performed to mimic the catalytic conformations of AAD in human UDP-glucuronosyltransferases (UGTs), while the predicted binding energies and distances between the deprotonated C-6 phenolic group of AAD and the glucuronyl moiety of UDPGA in each tested human UGT isoenzyme were measured. The mitochondrial membrane potentials (MMP) and reactive oxygen species (ROS) levels in HK-2 cells treated with either AAI, or AAD, or AAD O-glucuronide were tested, to elucidate the impact of O-glucuronidation on the nephrotoxicity of AAD. RESULTS: AAD could be rapidly metabolized in human liver and intestinal microsomes (HLM and HIM, respectively) to form a mono-glucuronide, which was purified and fully characterized as AAD-6-O-ß-D-glucuronide (AADG) by NMR. UGT1A1 was the predominant enzyme responsible for AAD-6-O-glucuronidation, while UGT1A9 contributed to a lesser extent. AAD-6-O-glucuronidation in HLM, HIM, UGT1A1 and UGT1A9 followed Michaelis-Menten kinetics, with the Km values of 4.27 µM, 9.05 µM, 3.87 µM, and 7.00 µM, respectively. Docking simulations suggested that AAD was accessible to the catalytic cavity of UGT1A1 or UGT1A9 and formed catalytic conformations. Further investigations showed that both AAI and AAD could trigger the elevated intracellular ROS levels and induce mitochondrial dysfunction and in HK-2 cells, but AADG was hardly to trigger ROS accumulation and mitochondrial dysfunction. CONCLUSION: Collectively, UGT1A-catalyzed AAD 6-O-glucuronidation represents a crucial detoxification pathway of this naturally occurring AAI analogs in humans, which is very different from that of AAI.


Asunto(s)
Ácidos Aristolóquicos , Enfermedades Mitocondriales , Humanos , Ácidos Aristolóquicos/toxicidad , Glucurónidos/metabolismo , Microsomas Hepáticos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Glucuronosiltransferasa/metabolismo , Cinética , Catálisis , Uridina Difosfato/metabolismo
12.
J Environ Manage ; 357: 120725, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38554454

RESUMEN

Since the electroplating industry is springing up, effective control of phosphate has attracted global concerns. In this study, a novel biosorbent (MIL-88@CS-HDG) was synthesized by loading a kind of Fe-based metal organic framework called MIL-88 into chitosan hydrogel beads and applied in deep treatment of phosphate removal in electroplating wastewater. The adsorption capacities of H2PO4- on MIL-88@CS-HDG could reach 1.1 mmol/g (corresponding to 34.1 mg P/g and 106.7 mg H2PO4-/g), which was 2.65% higher than that on single MOF powders and chitosan hydrogel beads. The H2PO4- adsorption was well described by the Freundlich isotherm model. Over 90% H2PO4- could be adsorbed at contact time of 3 h. It could keep high adsorption capacity in the pH range from 2 to 7, which had a wider pH range of application compared with pure MIL-88. Only NO3- and SO42- limited the adsorption with the reduction rate of 11.42% and 23.23%, proving it tolerated most common co-existing ions. More than 92% of phosphorus could be recovered using NaOH and NaNO3. Electrostatic attraction between Fe core and phosphorus in MIL-88@CS-HDG and ion exchange played the dominant role. The recovered MIL-88@CS-HDG remained stable and applicable in the treatment process of real electroplating wastewater even after six adsorption-regeneration cycles. Based on the removal properties and superb regenerability, MIL-88@CS-HDG is potentially applicable to practical production.


Asunto(s)
Quitosano , Contaminantes Químicos del Agua , Fosfatos , Hidrogeles , Quitosano/química , Aguas Residuales , Galvanoplastia , Fósforo , Adsorción , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno , Cinética
13.
J Environ Manage ; 357: 120727, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38555844

RESUMEN

The urgent concerns of controlling water body eutrophication and the alleviating phosphorus shortage have led to an urgent need for action. The removal of phosphate from polluted waters and its reuse are essential for the prevention of eutrophication and for the sustainable utilization of phosphate resources. In this study, modified attapulgite with different Ca:Mg molar ratios was synthesized to facilitate the recovery of phosphate, with subsequent use of soil fertilizer. Ca-Mg modified attapulgite with the optimal ratio (ACM-5:3) exhibited an exceptional adsorption quality, achieving a maximum adsorption capacity of 63.2 mg/g. The pseudo-second-order model and Langmuir model could well describe the adsorption kinetics and isotherms, respectively. The adsorption mechanism analyses suggested that the interaction between ACM-5:3 and phosphate depended mainly on ion exchange and electrostatic attraction. Moreover, phosphate-laden-ACM-5:3 demonstrated a significant potential as a phosphorus-releasing fertilizer. It could promote corn growth by ensuring a continuous supply of phosphorus and minimizing phosphorus runoff losses. The above results suggested that ACM-5:3 was a potential adsorbent for efficient phosphate removal and recovery.


Asunto(s)
Fosfatos , Compuestos de Silicona , Contaminantes Químicos del Agua , Fertilizantes , Compuestos de Magnesio , Fósforo , Adsorción , Cinética , Contaminantes Químicos del Agua/análisis
14.
Int J Biol Macromol ; 265(Pt 1): 130914, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38492702

RESUMEN

An innovative and simple nanocomposite denoted as MHNTs@PEI was synthesized for gallic acid (GA) analytical sample pretreatment. Polyethyleneimine (PEI) functionalized was binded onto magnetic halloysite nanotubes (MHNTs) to inhence adsorption capacity. MHNTs@PEI was obtained only through two steps modification (amination and PEI modification). Characterizations showed that there are layers of synthetic PEI on the tubular structure of the material and magnetic spheres on its surface, both indicating successful synthesis of the nanocomposite. Furthermore, the adsorption isotherms and kinetic modeling showed that the Langmuir model and pseudo-first-order model fit the adsorption data, respectively. MHNTs@PEI achieved an adsorption capacity of 158 mg·g-1. Overall, the abundant adsorption sites significantly improved the adsorption performance of the MHNTs@PEI. Regeneration tests demonstrated that the MHNTs@PEI exhibits effective adsorption, even after undergoing five consecutive cycles. Optimization of key parameters (ratio, volume of elution, elution time and frequency) in the process of adsorption and desorption was also conducted. The limit of detection (LOD) and that of the quantification (LOQ) were 0.19 and 0.63 µg·mL-1, respectively, and the recoveries were 95.67-99.43 %. Finally, the excellent magnetism (43.5 emu·g-1) and the adsorption feature of MHNTs@PEI enabled its successful utilization in analytical sample pretreatment through the extraction of GA from green tea.


Asunto(s)
Nanotubos , Contaminantes Químicos del Agua , Arcilla , Polietileneimina/química , Ácido Gálico , , Nanotubos/química , Adsorción , Fenómenos Magnéticos , Cinética
15.
Huan Jing Ke Xue ; 45(2): 898-908, 2024 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-38471928

RESUMEN

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.


Asunto(s)
Sulfametoxazol , Contaminantes Químicos del Agua , Sulfametoxazol/química , Adsorción , Espectroscopía Infrarroja por Transformada de Fourier , Agua , Contaminantes Químicos del Agua/análisis , Carbón Orgánico/química , Fósforo , Cinética , Fenómenos Magnéticos
16.
Scand J Med Sci Sports ; 34(3): e14595, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38458991

RESUMEN

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.


Asunto(s)
Rendimiento Atlético , Cafeína , Humanos , Masculino , Fenómenos Biomecánicos , Cafeína/farmacología , Cinética , Aceleración , Suplementos Dietéticos
17.
Bioresour Technol ; 399: 130560, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460563

RESUMEN

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.


Asunto(s)
Consorcios Microbianos , Triticum , Cinética , Carbohidratos , Bebidas Alcohólicas , Hidrólisis
18.
Environ Sci Pollut Res Int ; 31(16): 24064-24076, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438637

RESUMEN

The efficient development of selective materials for uranium recovery from wastewater and seawater is crucial for the utilization of uranium resources and environmental protection. The potential of graphene oxide (GO) as an effective adsorbent for the removal of environmental contaminants has been extensively investigated. Further modification of the functional groups on the basal surface of GO can significantly enhance its adsorption performance. In this study, a novel poly(amidoxime-hydroxamic acid) functionalized graphene oxide (pAHA-GO) was synthesized via free radical polymerization followed by an oximation reaction, aiming to enhance its adsorption efficiency for U(VI). A variety of characterization techniques, including SEM, Raman spectroscopy, FT-IR, and XPS, were employed to demonstrate the successful decoration of amidoxime and hydroxamic acid functional groups onto GO. Meanwhile, the adsorption of U(VI) on pAHA-GO was studied as a function of contact time, adsorbent dosage, pH, ionic strength, initial U(VI) concentration, and interfering ions by batch-type experiments. The results indicated that the pAHA-GO exhibited excellent reuse capability, high stability, and anti-interference ability. Specially, the U(VI) adsorption reactions were consistent with pseudo-second-order and Langmuir isothermal adsorption models. The maximum U(VI) adsorption capacity was evaluated to be 178.7 mg/g at pH 3.6, displaying a higher U(VI) removal efficiency compared with other GO-based adsorbents in similar conditions. Regeneration of pAHA-GO did not significantly influence the adsorption towards U(VI) for up to four sequential cycles. In addition, pAHA-GO demonstrated good adsorption capacity stability when it was immersed in HNO3 solution at different concentrations (0.1-1.0 mol/L) for 72 h. pAHA-GO was also found to have anti-interference ability for U(VI) adsorption in seawater with high salt content at near-neutral pH condition. In simulated seawater, the adsorption efficiency was above 94% for U(VI) across various initial concentrations. The comprehensive characterization results demonstrated the involvement of oxygen- and nitrogen-containing functional groups in pAHA-GO in the adsorption process of U(VI). Overall, these findings demonstrate the feasibility of the pAHA-GO composite used for the capture of U(VI) from aqueous solutions.


Asunto(s)
Grafito , Oximas , Uranio , Uranio/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Agua , Adsorción , Cinética
19.
J Environ Manage ; 356: 120502, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38479281

RESUMEN

Effective removal of phosphorus from water is crucial for controlling eutrophication. Meanwhile, the post-disposal of wetland plants is also an urgent problem that needs to be solved. In this study, seedpods of the common wetland plant lotus were used as a new raw material to prepare biochar, which were further modified by loading nano La(OH)3 particles (LBC-La). The adsorption performance of the modified biochar for phosphate was evaluated through batch adsorption and column adsorption experiments. Adsorption performance of lotus seedpod biochar was significantly improved by La(OH)3 modification, with adsorption equilibrium time shortened from 24 to 4 h and a theoretical maximum adsorption capacity increased from 19.43 to 52.23 mg/g. Moreover, LBC-La maintained a removal rate above 99% for phosphate solutions with concentrations below 20 mg/L. The LBC-La exhibited strong anti-interference ability in pH (3-9) and coexisting ion experiments, with the removal ratio remaining above 99%. The characterization analysis indicated that the main mechanism is the formation of monodentate or bidentate lanthanum phosphate complexes through inner sphere complexation. Electrostatic adsorption and ligand exchange are also the mechanisms of LBC-La adsorption of phosphate. In the dynamic adsorption experiment of simulated wastewater treatment plant effluent, the breakthrough point of the adsorption column was 1620 min, reaching exhaustion point at 6480 min, with a theoretical phosphorus saturation adsorption capacity of 6050 mg/kg. The process was well described by the Thomas and Yoon-Nelson models, which indicated that this is a surface adsorption process, without the internal participation of the adsorbent.


Asunto(s)
Lotus , Contaminantes Químicos del Agua , Fósforo , Aguas Residuales , Fosfatos/química , Carbón Orgánico , Adsorción , Lantano/química , Contaminantes Químicos del Agua/química , Semillas , Cinética
20.
Int J Biol Macromol ; 267(Pt 1): 131150, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38556236

RESUMEN

Gut microbial ß-glucuronidases (gmß-GUS) played crucial roles in regulating a variety of endogenous substances and xenobiotics on the circulating level, thus had been recognized as key modulators of drug toxicity and human diseases. Inhibition or inactivation of gmß-GUS enzymes has become a promising therapeutic strategy to alleviate drug-induced intestinal toxicity. Herein, the Rhodiola crenulata extract (RCE) was found with potent and broad-spectrum inhibition on multiple gmß-GUS enzymes. Subsequently, the anti-gmß-GUS activities of the major constituents in RCE were tested and the results showed that 1,2,3,4,6-penta-O-galloyl-ß-d-glucopyranose (PGG) acted as a strong and broad-spectrum inhibitor on multiple gmß-GUS (including EcGUS, CpGUS, SaGUS, and EeGUS). Inhibition kinetic assays demonstrated that PGG effectively inhibited four gmß-GUS in a non-competitive manner, with the Ki values ranging from 0.12 µM to 1.29 µM. Docking simulations showed that PGG could tightly bound to the non-catalytic sites of various gmß-GUS, mainly via hydrogen bonding and aromatic interactions. It was also found that PGG could strongly inhibit the total gmß-GUS activity in mice feces, with the IC50 value of 1.24 µM. Collectively, our findings revealed that RCE and its constituent PGG could strongly inhibit multiple gmß-GUS enzymes, suggesting that RCE and PGG could be used for alleviating gmß-GUS associated enterotoxicity.


Asunto(s)
Inhibidores Enzimáticos , Microbioma Gastrointestinal , Simulación del Acoplamiento Molecular , Rhodiola , Rhodiola/química , Animales , Ratones , Microbioma Gastrointestinal/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Medicina Tradicional Tibetana , Cinética , Masculino
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