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1.
Chemosphere ; 338: 139530, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37459924

RESUMEN

Micro/nanomotors that can promote mass transport have attracted more and more research concern in the photocatalysis field. Here we first report a newly-designed hierarchical α-Fe2O3/ZnFe2O4/Mn2O3 magnetic micromotor as a heterogeneous photocatalyst for the degradation of cationic dye methylene blue (MB) from wastewater. The resulting three-dimensional (3D) flower-like hollow Janus micromotors are fabricated through a green and scalable strategy, in which each component has different functions. ZnFe2O4 microspheres serve as a magnetic scaffold for the nucleation and growth of α-Fe2O3 nanosheets and for the recycling of the micromachine. α-Fe2O3 nanosheets have shown great potential as an ideal semiconductor material for the photocatalytic decontamination of pollutants. Mn2O3 nanoparticles are mainly utilized as a catalyst to produce O2 bubbles to propel the autonomic movement of the micromotors in the presence of H2O2 fuel and also as a Fenton-like catalyst to decompose H2O2 to generate reactive oxygen species. Furthermore, the resultant micromotors exhibited linear-like motion form with an average speed of 189.1 µm s-1 in 5 wt% H2O2 solution. Moreover, the self-driven micromotors exhibited a superior catalytic degradation property toward MB, which was attributed to the synergistic effect of heterogeneous photocatalyst and the boosted micro-mixing and mass transfer caused by the vigorous motion of the micro-actuator. The possible degradation intermediates and passways of MB by α-Fe2O3/ZnFe2O4/Mn2O3 micromotor were identified with time of flight mass spectroscopy (TOF-MS). The 3D Janus micromotors have the potential to be used as a high-efficiency and active heterogeneous photocatalyst for the degradation of organic pollutants.


Asunto(s)
Peróxido de Hidrógeno , Aguas Residuales , Peróxido de Hidrógeno/química , Microesferas
2.
RSC Adv ; 13(22): 15031-15040, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37200703

RESUMEN

The inexpensive and highly efficient electrocatalysts toward oxygen evolution reaction (OER) in water splitting electrolysis have displayed promising practical applications to relieve energy crisis. Herein, we prepared a high-yield and structurally regulated bimetallic cobalt-iron phosphide electrocatalyst by a facile one-pot hydrothermal reaction and subsequent low-temperature phosphating treatment. The tailoring of nanoscale morphology was achieved by varying the input ratio and phosphating temperature. Thus, an optimized FeP/CoP-1-350 sample with the ultra-thin nanosheets assembled into a nanoflower-like structure was obtained. FeP/CoP-1-350 heterostructure displayed remarkable activity toward the OER with a low overpotential of 276 mV at a current density of 10 mA cm-2, and a low Tafel slope of only 37.71 mV dec-1. Long-lasting durability and stability were maintained with the current with almost no obvious fluctuation. The enhanced OER activity was attributed to the presence of copious active sites from the ultra-thin nanosheets, the interface between CoP and FeP components, and the synergistic effect of Fe-Co elements in the FeP/CoP heterostructure. This study provides a feasible strategy to fabricate highly efficient and cost-effective bimetallic phosphide electrocatalysts.

3.
Biomed Pharmacother ; 161: 114379, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36827711

RESUMEN

Chrysanthemum morifolium Ramat. is a kind of food and drug dual-use traditional Chinese medicine possessing multiple pharmacological and biochemical benefits. In our study, a rapid and high-throughput method based on Surface plasmon resonance (SPR) biosensor technology was developed and verified for screening potential xanthine oxidase (XOD) inhibitors exemplarily in the Chrysanthemum morifolium Ramat. Coupled with ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS), 14 XOD-binders were identified. In the SPR-based biosensor and molecular docking analysis, most compounds exhibited a strong affinity and binding kinetic property (association rate constant, Kon and dissociation rate constant, Koff) for XOD and could be regarded as potential inhibitors. More importantly, to further accurately assess target occupancy of candidate compounds in vivo, a mathematical model was established and verified involving three crucial intrinsic kinetic processes (Pharmacokinetics, Binding kinetic and Target kinetic). Overall, the proposed screening and assessment strategy could be proved an effective theoretical basis for further pharmacodynamic evaluation.


Asunto(s)
Chrysanthemum , Xantina Oxidasa , Chrysanthemum/química , Simulación del Acoplamiento Molecular , Cinética , Cromatografía Líquida de Alta Presión/métodos , Inhibidores Enzimáticos
4.
Biomolecules ; 12(12)2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36551294

RESUMEN

PURPOSE: Inhibition of dipeptidyl peptidase-IV (DPP-IV) is an effective therapy for treating type II diabetes (T2D) that has been widely applied in clinical practice. We aimed to evaluate the DPP-IV inhibitory properties of ginger protease hydrolysate (GPH) and propose a comprehensive approach to screen and evaluate DPP-IV inhibitors. METHODS: We evaluated the in vitro inhibitory properties of fish skin gelatin hydrolysates produced by five proteases, namely, neutral protease, alkaline protease, bromelain, papain, and ginger protease, toward DPP-IV. We screened the most potent DPP-IV inhibitory peptide (DIP) using liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with in silico analysis. Next, surface plasmon resonance (SPR) technology was innovatively introduced to explore the interactions between DPP-IV and DIP, as well as the IC50. Furthermore, we performed oral administration of DIP in rats to study its in vivo absorption. RESULTS: GPH displayed the highest degree of hydrolysis (20.37%) and DPP-IV inhibitory activity (65.18%). A total of 292 peptides from the GPH were identified using LC-MS/MS combined with de novo sequencing. Gly-Pro-Hyp-Gly-Pro-Pro-Gly-Pro-Gly-Pro (GPXGPPGPGP) was identified as the most potent DPP-IV inhibitory peptide after in silico screening (Peptide Ranker and molecular docking). Then, the in vitro study revealed that GPXGPPGPGP had a high inhibitory effect on DPP-IV (IC50: 1012.3 ± 23.3 µM) and exhibited fast kinetics with rapid binding and dissociation with DPP-IV. In vivo analysis indicated that GPXGPPGPGP was not absorbed intact but partially, in the form of dipeptides and tripeptides. CONCLUSION: Overall, the results suggested that GPH would be a natural functional food for treating T2D and provided new ideas for searching and evaluating potential antidiabetic compounds. The obtained GPXGPPGPGP can be structurally optimized for in-depth evaluation in animal and cellular experiments.


Asunto(s)
Diabetes Mellitus Tipo 2 , Tilapia , Ratas , Animales , Gelatina/química , Cromatografía Liquida , Simulación del Acoplamiento Molecular , Espectrometría de Masas en Tándem , Péptidos/farmacología , Péptidos/química
5.
Molecules ; 27(15)2022 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-35956951

RESUMEN

(1) Methods: An integrated strategy, including in vitro study (degree of hydrolysis (DH) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity) and in vivo study (absorption after oral administration in rats), was developed to evaluate the properties of the fish skin gelatin hydrolysates prepared using different proteases (pepsin, alkaline protease, bromelain, and ginger protease). Meanwhile, in order to identify the hydrolysis site of ginger protease, the peptides in the ginger protease-degraded collagen hydrolysate (GDCH) were comprehensively characterized by liquid chromatography/tandem mass spectrometry (LC-MS) method. (2) Results: The GDCH exhibited the highest DH (20.37%) and DPPH radical scavenging activity (77.73%), and in vivo experiments showed that the GDCH was more efficiently absorbed by the gastrointestinal tract. Further oral administration experiments revealed that GDCH was not entirely degraded to free amino acids and can be partially absorbed as dipeptides and tripeptides in intact forms, including Pro-Hyp, Gly-Pro-Hyp, and X-Hyp-Gly tripeptides. LC-MS results determined the unique substrate specificity of ginger protease recognizing Pro and Hyp at the P2 position based on the amino acids at the P2 position from the three types of tripeptides (Gly-Pro-Y, X-Hyp-Gly, and Z-Pro-Gly) and 136 identified peptides (>4 amino acids). Interestingly, it suggested that ginger protease can also recognize Ala in the P2 position. (3) Conclusions: This study comprehensively evaluated the properties of GDCH by combining in vitro and in vivo strategies, and is the first to identify the cleavage site of ginger protease by LC-MS technique. It provides support for the follow-up study on the commercial applications of ginger protease and bioactivities of the hydrolysate produced by ginger protease.


Asunto(s)
Zingiber officinale , Aminoácidos , Animales , Cromatografía Liquida , Colágeno/química , Estudios de Seguimiento , Péptido Hidrolasas/química , Péptidos , Ratas , Espectrometría de Masas en Tándem , Tecnología
6.
Front Pharmacol ; 12: 759157, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34912220

RESUMEN

The study of screening active constituents from traditional Chinese medicine (TCM) is important for explicating the mechanism of action of TCM and further evaluating the safety and efficacy effectively. However, detecting and identifying the active constituents from complicated biological samples still remain a challenge. Here, a practical, quick, and novel integrated strategy from in vitro, in situ, in vivo to in silico for rapidly screening the active constituents was developed. Firstly, the chemical profile of TCM in vitro was identified using UPLC-Q Exactive-Orbitrap HRMS. Secondly, the in situ intestinal perfusion with venous sampling (IPVS) method was used to investigate the intestinal absorption components. Thirdly, after intragastric administration of the TCM extract, the in vivo absorbed prototype components were detected and identified. Finally, the target network pharmacology approach was applied to explore the potential targets and possible mechanisms of the absorbed components from TCM. The reliability and availability of this approach was demonstrated using Tongfengding capsule (TFDC) as an example of herbal medicine. A total of 141 compounds were detected and identified in TFDC, and among them, 64 components were absorbed into the plasma. Then, a total of 35 absorbed bioactive components and 50 related targets shared commonly by compounds and gout were integrated via target network pharmacology analysis. Ultimately, the effects of the absorbed components on metabolism pathways were verified by experiments. These results demonstrated that this original method may provide a practical tool for screening bioactive compounds from TCM treating particular diseases. Furthermore, it also can clarify the potential mechanism of action of TCM and rationalize the application of TFDC as an effective herbal therapy for gout.

7.
Front Pharmacol ; 12: 746594, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34737703

RESUMEN

We aimed to develop a physiological-based pharmacokinetic and dipepidyl peptidase 4 (DPP-4) occupancy model (PBPK-DO) characterized by two simultaneous simulations to predict pharmacokinetic (PK) and pharmacodynamic changes of saxagliptin and metabolite M2 in humans when coadministered with CYP3A4 inhibitors or inducers. Ketoconazole, delavirdine, and rifampicin were selected as a CYP3A4 competitive inhibitor, a time-dependent inhibitor, and an inducer, respectively. Here, we have successfully simulated PK profiles and DPP-4 occupancy profiles of saxagliptin in humans using the PBPK-DO model. Additionally, under the circumstance of actually measured values, predicted results were good and in line with observations, and all fold errors were below 2. The prediction results demonstrated that the oral dose of saxagliptin should be reduced to 2.5 mg when coadministrated with ketoconazole. The predictions also showed that although PK profiles of saxagliptin showed significant changes with delavirdine (AUC 1.5-fold increase) or rifampicin (AUC: a decrease to 0.19-fold) compared to those without inhibitors or inducers, occupancies of DPP-4 by saxagliptin were nearly unchanged, that is, the administration dose of saxagliptin need not adjust when there is coadministration with delavirdine or rifampicin.

8.
Front Pharmacol ; 12: 762756, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34712143

RESUMEN

Tongluo Yishen (TLYS) decoction is an herb that is extensively applied for the treatment of chronic kidney disease (CKD) in traditional Chinese medicine. In this study, 37 different dominant chemical constituents of TLYS were identified. Rats with unilateral ureteral obstruction (UUO) were used as animal models, and TLYS decoction was administered orally for 14 days. TLYS decoction reduced the levels of renal function indicators, serum creatinine levels and blood urea nitrogen levels and alleviated renal pathological changes. Gene Ontology (GO) and KEGG pathway analyses of RNA sequencing data showed that TLYS decoction had significant effects on biological processes, cellular components and molecular functions in UUO rats and that the phagosome (a membrane source in the early stages of autophagy), lysosome (an important component of autolysosome), and oxidation pathways (which contribute to mitochondrial function) might be related to the antifibrotic effects of TLYS decoction. Moreover, we found significant mitochondrial function impairment, including a decreased mitochondrial membrane potential (MMP) and an imbalance in mitochondrial dynamics, excessive oxidative stress, and activation of Pink1/Parkin-mediated mitophagy in UUO rats. Treatment with TLYS decoction significantly increased the MMP, normalized mitochondrial dynamics and ameliorated renal injury. Moreover, TLYS alleviated the mitophagy clearance deficiency. In conclusion, our study showed that TLYS decoction can ameliorate mitochondrial dynamics by reducing oxidative stress and regulating mitophagy, thereby relieving renal injury, protecting renal function, and reducing renal fibrosis. This study provides support for the application of and further research on TLYS decoction.

9.
Front Nutr ; 8: 677659, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34604271

RESUMEN

Screening functional food ingredients (FFI) from medicinal and edible plants (MEP) has still remained a great challenge due to the complexity of MEP and its obscure function mechanisms. Herein, an integrated strategy based on sequential metabolites identification approach, network pharmacology, molecular docking, and surface plasmon resonance (SPR) analysis was proposed for quickly identifying the active constituents in MEP. First, the sequential biotransformation process of MEP, including intestinal absorption and metabolism, and hepatic metabolism, was investigated by oral gavage, and intestinal perfusion with venous sampling method. Then the blood samples were analyzed by UPLC-Q Exactive Orbitrap HRMS. Second, the network pharmacology approach was used to explore the potential targets and possible mechanisms of the in vivo metabolites of MEP. Third, molecular docking and SPR approaches were used to verify the specific interactions between protein targets and representative ingredients. The proposed integrated strategy was successfully used to explore the heptoprotective components and the underlying molecular mechanism of Paeoniae Radix Alba (PRA). A total of 44 compounds were identified in blood samples, including 17 porotypes and 27 metabolites. The associated metabolic pathways were oxidation, methylation, sulfation, and glucuronidation. After further screening, 31 bioactive candidates and 377 related targets were obtained. In addition, the bioactive components contained in PRA may have therapeutic potentials for non-alcoholic fatty liver disease (NAFLD). The above results demonstrated the proposed strategy may provide a feasible tool for screening FFI and elaborating the complex function mechanisms of MEP.

10.
Biomed Pharmacother ; 139: 111664, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34243606

RESUMEN

The accurate quantitative determination of affinity and binding kinetics (BK) for tight binding inhibition is extraordinary important from both the continuous optimization of compounds, particularly in developing structure-activity relationships (SAR), and the prediction of in vivo target occupancy (TO). Due to the unique properties for tight binding inhibition that the inhibitors are characterized by the ultrahigh-affinity, relatively fast association to the target enzyme combined with extremely slow dissociation of the inhibitor-enzyme binary complex, the classical steady state equilibrium methods are no longer valid. Here, we made several recommendations of how to design the optimal experiments and apply special mathematical calculation approaches to quantitatively evaluate the accurate affinity and BK as the examples of two tight binding inhibitors against the xanthine oxidase (XO), as well as compared the differences in the results calculated from the different data analytical methods and analyzed the influence of these differences on the XO engagement in human. Analysis of the results displayed that the accurate apparent dissociation constant (Ki*,app) was 0.2 ± 0.06 nM for topiroxotstat and was 0.45 ± 0.2 nM for febuxostat; that on-rate (kon) was (4.3 ± 1.1) × 106 M-1s-1 for topiroxotstat and was(133.3 ± 3.5) × 106 M-1s-1 for febuxostat, and off-rate (koff) was (1.0±0.2) × 10-5 s-1 for topiroxotstat and was ≤ 0.16 × 10-5 s-1for febuxostat. Moreover, there were significant differences in the Ki*,app and koff values estimated using the appropriate specialized methods for tight binding inhibition versus classical steady state equilibrium methods, with the substantial differences of 14-fold and 32-fold reduction for topiroxostat, respectively, and of 9.6-fold and ≥ 213-fold reduction for febuxostat, while the kon values remain the moderate differences for the two inhibitors. The obvious greater AUC of XO engagement time courses and longer durations of above 70% engagement by the appropriate specialized methods for tight binding inhibition were observed that the results display the differences of 70.1% and 88%, respectively for topiroxostat and of 38.1% and 35.0%, respectively for febuxostat in human liver cell than by classical steady state equilibrium methods. Again, our studies provide several valuable recommendations of the optimal experiment protocols and appropriate analytical approaches for accurately quantitatively assessing the affinity and BK parameters as well as demonstrate the ability of our recommended methods to generate reliable data for tight binding inhibitors against XO.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Xantina Oxidasa/antagonistas & inhibidores , Xantina Oxidasa/metabolismo , Células Cultivadas , Febuxostat/farmacología , Humanos , Cinética , Unión Proteica/fisiología , Relación Estructura-Actividad
11.
Zhongguo Zhong Yao Za Zhi ; 46(7): 1822-1831, 2021 Apr.
Artículo en Chino | MEDLINE | ID: mdl-33982487

RESUMEN

Based on the target occupancy mathematical model, the binding kinetic process of potential active ingredients of lowering uric acid in Chrysanthemum morifolium with xanthine oxidase(XOD) was evaluated. The potential active ingredients of lowering uric acid in Ch. morifolium were screened by UPLC-Q-Exactivems MS technology, reference substance identification and in vitro enzymatic kinetics experiments. The binding kinetic parameters of xanthine oxidase and potential inhibitor in Ch. morifolium were determined by surface plasma resonance(SPR). The verified mathematical model of the XOD target occupancy evaluated the kinetic binding process of inhibitors and xanthine oxidase in vivo. According to UPLC-Q-Exactive MS and reference substance identification, 39 potential uric acid-lowering active ingredients in Ch. morifolium extracts were identified and the inhibitory activities of 23 compounds were determined. Three potential xanthine oxidase inhibitors were screened, namely genistein, luteolin, and apigenin. whose IC_(50 )were 1.23, 1.47 and 1.59 µmol·L~(-1), respectively. And the binding rate constants(K_(on)) were 1.26×10~6, 5.23×10~5 and 6.36×10~5 mol·L~(-1)·s~(-1), respectively. The dissociation rate constants(K_(off)) were 10.93×10~(-2), 1.59×10~(-2), and 5.3×10~(-2 )s~(-1), respectively. After evaluation by different administration methods, the three selected compounds can perform rapid and sustained inhibition of xanthine oxidase in vivo under combined administration. This study comprehensively evaluated the target occupancy process of three effective components in different ways of administration in vivo by UPLC-MS, concentration-response method, SPR technology and xanthine oxidase target occupancy model, which would provide a new research idea and method for screening active ingredients in traditional Chinese medicine.


Asunto(s)
Chrysanthemum , Preparaciones Farmacéuticas , Cromatografía Liquida , Flavonoides , Cinética , Espectrometría de Masas en Tándem , Xantina Oxidasa/metabolismo
12.
J Anal Methods Chem ; 2021: 6616854, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33628576

RESUMEN

Bupleuri Radix (Chaihu, in Chinese) is the principal drug in Xiaochaihu granules (XGs) that is a famous Chinese medicine preparation in China. Since previous analytical methods have not focused on the multiactive saikosaponins of Chaihu, it is difficult to effectively control the quality of XG on the market. In this manuscript, the simultaneous determination of 7 saikosaponins (saikosaponins C, I, H, A, B2, G, and B1) in XG by HPLC with charged aerosol detection (CAD) and confirmation by LC-Q-Orbitrap HRMS were described. The saikosaponins were purified on an SPE cartridge and determined on a Waters CORTECTS C18 column (4.6 mm × 150 mm, 2.7 µm) by gradient elution using 0.01% acetic acid aqueous solution and acetonitrile. The results showed good linearity with the r 2 values higher than 0.998 for all analytes. The average recoveries at three different concentration levels ranged from 80% to 109% and the intraday and interday precision (relative standard deviations, RSD%) were in the range of 1.0%∼1.9% and 1.4%∼2.1%, respectively. The established HPLC-CAD method was subsequently applied to 15 batches of XG to investigate the batch-to-batch consistency and controllability. The proposed method could potentially be used for the quality control of XG and also be helpful in the quality evaluation of Chaihu and its related preparations.

13.
Front Pharmacol ; 11: 423, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32317976

RESUMEN

Constipation is a common gastrointestinal disorder without effective treatment approach. Buzhongyiqi decoction (BZYQD) is a classical formula that has been commonly used for gastrointestinal disorders for nearly 1,000 years. In this study, we aimed to investigate the protective effect of BZYQD against loperamide-induced constipation and its potential mechanism. Rats with loperamide-induced constipation were orally administered BZYQD. BZYQD treatment obviously increased the small intestinal transit rate and alleviated colon tissue pathological damage. Subsequently, serum metabolomics study was performed to identify the metabolites affected by BZYQD. Metabolomics identified that the levels of 17 serum metabolites, including prostaglandin E2 (PGE2), arachidonic acid (AA), and inositol, were significantly changed in BZYQD-treated group compared with those in the loperamide-induced group. Pathway analysis revealed that those metabolites were mainly associated with arachidonic acid metabolism, biosynthesis of unsaturated fatty acids, ascorbate and aldarate metabolism, inositol phosphate metabolism. Additionally, BZYQD treatment down-regulated the cyclooxygenase-2 expression and decrease production of the proinflammatory mediator PGE2. Further study revealed that BZYQD administration decreased serum levels of the inflammatory factors IL-1ß and TNF-α, inhibited phosphorylation of the nuclear transcription factor NF-κB, and down-regulated expression of the inflammatory factors IL-1ß and IL-6 in the constipated rat colon. Moreover, BZYQD treatment also increased serum levels of inositol, motilin and gastrin, and promoted gastrointestinal motility. In conclusion, the present study suggested that BZYQD exerted a protective effect against loperamide-induced constipation, which may be associated with its role in regulation of multiple metabolic pathways.

14.
Colloids Surf B Biointerfaces ; 188: 110742, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31881409

RESUMEN

A novel core-shell Fe3O4/CoFe-LDH (layered double hydroxides) hybrid as a peroxidase mimic for the colorimetric detection of ascorbic acid was first fabricated via a facile two-step route. The resulting Fe3O4/CoFe-LDH hybrid exhibited much higher peroxidase-like catalytic activity for the oxidation of 3,3',5,5'- tetramethylbenzidine (TMB) with H2O2 than the pristine Fe3O4 and CoFe-LDH nanosheets owing to the unique hierarchical architecture containing more exposed active sites and the synergistic effect between Fe3O4 and CoFe-LDH. A sensitively and selectively visual sensor for the determination of ascorbic acid (AA) was successfully constructed based on the reduction effect of AA with enediol group on the formed oxidation of TMB, which exhibited a sensitive response to AA in the range of 0.5 ∼ 10 µM with the detection limit of 0.2 µM. Additionally, the Fe3O4/CoFe-LDH magnetic hybrid could be easily recycled by applying a magnetic field. This work provided a feasible means for the fabrication of magnetic nanomaterials with encouraging prospect in biosensing, environmental monitoring and medical diagnostics.


Asunto(s)
Ácido Ascórbico/análisis , Cobalto/química , Colorimetría , Compuestos Férricos/química , Hidróxidos/química , Hierro/química , Catálisis , Oxidación-Reducción , Tamaño de la Partícula , Propiedades de Superficie
15.
J Colloid Interface Sci ; 555: 234-244, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31386992

RESUMEN

This paper reports the first proof-of-concept of using bioinspired ZIF-8 based micromotors for efficient water remediation. Natural kapok fibers have unique hollow structure that contains cellulose and lignin, inspiring the design and fabrication of bubble-driving tubular micromotors as an active self-propelled micromachine for the removal of organic pollutants from water. The outer dense ZIF-8 layer can adsorb organic pollutants on the micromotors, and the inner catalyst acts as the engine decomposing fuel H2O2 for providing bubble propulsion. The magnetic γ-Fe2O3 enables the external magnetic control movement and recovery of micromotors. The maximum adsorption capacity of ZIF-8-based magnetic micromotors toward Congo red and doxycycline were high as 394 and 242 mg g-1, respectively, mainly due to the enhanced micromotor-pollutant contacts by their autonomous motion and the resulting mixing associated effect. This novel ZIF-8 micromotor also showed outstanding stability and reusability in aqueous solution, indicating that their great potential for future application in water treatment.

16.
Drug Test Anal ; 9(11-12): 1779-1787, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28842970

RESUMEN

Musk, the dried secretion of the musk pod (sac) of adult male musk deer, has been used as traditional Chinese Medicine (TCM) in China and south-east Asian countries for thousands of years. Due to the anabolic steroid component in this TCM, musk preparations have been included in the list of medical products containing prohibited substances employed for doping by the State Food and Drug Administration of China. The application of musk pod formulation was claimed to be responsible for some adverse analytical findings (AAFs) in the 2011 FIFA Women's World Cup. Our preliminary study has suggested that musk ingestion did not lead to AAFs of doping control with the single dosage of 100 mg. However, the influences of musk administration in large and multi dosage are still unclear. The aim of this study is to further investigate the influences of musk administration for doping control. Wild and domestic deer musk samples were collected. The concentrations and δ13 C-values of steroids in musk were analyzed. In an excretion study, 200 and 100 mg of wild and domestic deer musk samples were administrated by 29 subjects, respectively. Fluctuations in steroid profile could be observed, and the ratio of 5α-androstane-3α,17ß-diol to 5ß-androstane-3α,17ß-diol was more sensitive than other parameters. In the IRMS test, the ∆Δδ13 C-value between endogenous reference compound and etiocholanolone was a sensitive parameter, and AAFs were obtained. It is the first time to confirm with excretion study that musk administration could lead to positive result of doping control. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Androstanos/administración & dosificación , Doping en los Deportes , Etiocolanolona/administración & dosificación , Esteroides/administración & dosificación , Androstanos/química , China , Etiocolanolona/química , Ácidos Grasos Monoinsaturados , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Esteroides/química
17.
Mar Drugs ; 15(6)2017 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-28629153

RESUMEN

Fucoidan, a fucose-containing sulfated polysaccharide with diverse biological functions, is mainly recovered from brown algae. In this study, we utilized a compressional-puffing process (CPP) to pretreat Sargassum crassifolium (SC) and extracted fucoidans from SC by warm water. Three fucoidan extracts (SC1: puffing at 0 kg/cm²; SC2: puffing at 1.7 kg/cm²; and SC3: puffing at 6.3 kg/cm²) were obtained, and their composition, and antioxidant and neuroprotective activities were examined. The results suggest that CPP decreased the bulk density of algal samples, expanded the algal cellular structures, and eliminated the unpleasant algal odor. The extraction yields of fucoidans were increased and impurities of fucoidans were decreased by increasing the pressures used in CPP. The SC1-SC3 extracts displayed various characteristics of fucoidan as illustrated by the analyses of composition, Fourier transform infrared (FTIR) spectroscopy, and molecular weight. All three extracts SC1-SC3 showed antioxidant activity dose-dependently. Although both SC1 and SC2 possessed high and similar neuronal protective properties, SC2 showed a higher extraction yield, higher efficacy in the reversion of H2O2-induced cytotoxicity in rat pheochromocytoma PC-12 cells, and lower impurities compared with SC1, and thus SC2 is suggested as a good candidate for a therapeutic agent in the preventive treatment of neurodegenerative diseases.


Asunto(s)
Antioxidantes/farmacología , Fármacos Neuroprotectores/farmacología , Polisacáridos/farmacología , Sargassum/química , Animales , Células PC12 , Polisacáridos/análisis , Ratas
18.
Food Chem ; 197 Pt B: 1121-9, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26675848

RESUMEN

Fucoidan, a multifunctional marine polymer, is normally extracted from brown algae via extensive use of acid, solvent or high temperature water and a long reaction time. In present study, we developed a novel compressional-puffing-hydrothermal extraction (CPHE) process which primarily decomposes the cellular structure of algae and facilitates the release of fucoidan by hot water extraction. The CPHE process provides a number of advantages including simple procedure, reactant-saving, reduced pollution, and feasibility for continuous production. Sargassum glaucescens (SG) was utilized in this study, and the maximum extraction yield of polysaccharide was approximately 9.83 ± 0.11% (SG4). Thin layer chromatography (TLC), Fourier transform infrared (FTIR) analysis, and measurements of monosaccharide composition, fucose, sulfate, and uronic acid contents revealed that the extracted polysaccharide showed characteristics of fucoidan. All extracts exhibited antioxidant activities, and thus, further exploration of these extracts as potential natural and safe antioxidant agents is warranted.


Asunto(s)
Antioxidantes/farmacología , Extractos Vegetales/farmacología , Polisacáridos/aislamiento & purificación , Sargassum , Polisacáridos/farmacología , Sargassum/química
19.
Zhongguo Zhong Yao Za Zhi ; 41(7): 1188-1191, 2016 Apr.
Artículo en Chino | MEDLINE | ID: mdl-28879729

RESUMEN

The information of drug deposition in the intestine is required in the study for the drug absorption in biopharmaceutics classification system (BCS). To illustrate the impacts of gut wall metabolism on the absorption, metabolism of multiple components in Chuanxiong Rhizoma in gut wall was tested by rat S9 incubation in vitro. The chemical fingerprint technology was used in this study to simultaneously detect multiple components in Chuanxiong, and peak areas before and after S9 incubation were compared. The results showed that senkyunolide I and several constituents were metabolized by gut wall, and one new metabolite was founded. However, ferulic acid and other compounds remained unchanged after incubation. Therefore, the subsequent intestinal permeability of multiple components in Chuanxiong that were not metabolized in the intestine was suggested to be detected directly by in situ single-pass intestinal perfusion (SPIP).Nonetheless, the intestinal permeability of the constituents that were metabolized in the intestine shall be explored by appropriate approaches.


Asunto(s)
Medicamentos Herbarios Chinos/metabolismo , Absorción Intestinal , Mucosa Intestinal/metabolismo , Animales , Biofarmacia , Permeabilidad , Ratas , Rizoma/química
20.
Talanta ; 139: 67-74, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25882410

RESUMEN

Ezetimibe is a novel lipid-lowering agent that inhibits intestinal absorption of dietary and biliary cholesterol. In the present work, a simple, sensitive and reproducible gradient reverse phase high performance liquid chromatographic (RP-HPLC) method for separation and determination of the related substances of ezetimibe was developed and validated. Eleven potential process-related impurities (starting materials, (3S,4S,3'S)-isomer, degradants and byproducts) were identified in the crude samples. Tentative structures for all the impurities were assigned primarily based on comparison of their retention time and mass spectrometric data with that of available standards and references. This method can be applied to routine analysis in quality control of both bulk drugs and commercial tablets. Separation of all these compounds was performed on a Phenomenex Luna Phenyl-Hexyl (100mm×4.6mm, 5µm) analytical column. The mobile phase-A consists of acetonitrile-water (pH adjusted to 4.0 with phosphoric acid)-methanol at 15:75:10 (v/v/v), and mobile phase-B contains acetonitrile. The eluted compounds were monitored at 210nm. Ezetimibe was subjected to hydrolytic, acid, base, oxidative, photolytic and thermal stress conditions as per ICH serves to generate degradation products that can be used as a worst case to assess the analytical method performance. The drug showed extensive degradation in thermal, acid, oxidative, base and hydrolytic stress conditions, while it was stable to photolytic degradation conditions. The main degradation product formed under thermal, acid, oxidative, base and hydrolytic stress conditions corresponding to (2R,3R,6S)-N, 6-bis(4-fluorophenyl)-2-(4-hydroxyphenyl)-oxane-3-carboxamide (Ezetimibe tetrahydropyran impurity) was characterized by LC-MS/MS analysis. The degradation products were well resolved from the main peak and its impurities, thus proved the stability-indicating power of the method. The developed method was validated as per international conference on harmonization (ICH) guidelines with respect to specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, precision and robustness.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Estabilidad de Medicamentos , Ezetimiba/análisis , Ezetimiba/química , Espectrometría de Masas en Tándem/métodos , Anticolesterolemiantes/análisis , Anticolesterolemiantes/química , Contaminación de Medicamentos , Ezetimiba/aislamiento & purificación , Humanos , Hidrólisis , Límite de Detección , Reproducibilidad de los Resultados , Comprimidos
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