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1.
Acta Biochim Biophys Sin (Shanghai) ; 56(4): 621-633, 2024 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-38516704

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, with a global prevalence of 25%. Patients with NAFLD are more likely to suffer from advanced liver disease, cardiovascular disease, or type II diabetes. However, unfortunately, there is still a shortage of FDA-approved therapeutic agents for NAFLD. Lian-Mei-Yin (LMY) is a traditional Chinese medicine formula used for decades to treat liver disorders. It has recently been applied to type II diabetes which is closely related to insulin resistance. Given that NAFLD is another disease involved in insulin resistance, we hypothesize that LMY might be a promising formula for NAFLD therapy. Herein, we verify that the LMY formula effectively reduces hepatic steatosis in diet-induced zebrafish and NAFLD model mice in a time- and dose-dependent manner. Mechanistically, LMY suppresses Yap1-mediated Foxm1 activation, which is crucial for the occurrence and development of NAFLD. Consequently, lipogenesis is ameliorated by LMY administration. In summary, the LMY formula alleviates diet-induced NAFLD in zebrafish and mice by inhibiting Yap1/Foxm1 signaling-mediated NAFLD pathology.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Enfermedad del Hígado Graso no Alcohólico , Humanos , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Lipogénesis , Pez Cebra , Diabetes Mellitus Tipo 2/metabolismo , Hígado/metabolismo , Dieta Alta en Grasa , Factores de Transcripción/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Lípidos , Ratones Endogámicos C57BL , Proteína Forkhead Box M1/metabolismo
2.
Phytomedicine ; 124: 155296, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38176276

RESUMEN

BACKGROUND: Diabetes belongs to the most prevalent metabolic diseases worldwide, which is featured with insulin resistance, closely associated with obesity and urgently needs to be treated. Baicalin, belonging to natural flavonoids, has been reported to inhibit oxidative stress or inflammatoin. PURPOSE: This study investigated the properties of baicalin on modulating abnormal glucolipid metabolism, as well as the underlying in-vitro and in-vivo mechanisms. METHODS: Insulin-resistant (IR)-HepG2 cells were stimulated by dexamethasone (20 µM) and high glucose (50 mM) for 48 h and incubated with or without baicalin or metformin for another 16 h. Male C57BL/6 J mice were fed with a high-fat diet (HFD, 60 % kcal% fat) during the total 14 weeks. Obese mice were then administered with baicalin (50 and 100 mg/kg) or vehicle solution everyday through oral gavage during the last 4-week period. Moreover, baicalin metabolisms in vitro and in vivo were determined using UPLC/MS/MS to study its metabolism situation. RESULTS: Exposure to dexamethasone and high glucose damaged the abilities of glycogen synthesis and glucose uptake with elevated oxidative stress and increased generation levels of advanced glycation end-products (AGEs) in HepG2 cells. These impairments were basically reversed by baicalin treatment. Four-week oral administration with baicalin ameliorated hyperglycemia and dyslipidemia in HFD-induced obese and pre-diabetic mice. Downregulation of IRS/PI3K/Akt signaling pathway accomplished with reduced GLUT4 expression and enhanced GSK-3ß activity was observed in insulin resistant HepG2 cells as well as liver tissues from pre-diabetic mice; and such effect was prevented by baicalin. Moreover, baicalin and its matabolites were detected in IR-HepG2 cells and mouse plasma. CONCLUSION: The study illustrated that baicalin alleviated insulin resistance by activating insulin signaling pathways and inhibiting oxidative stress and AGEs production, revealing the potential of baicalin to be a therapeutic natural flavonoid against hepatic insulin and glucose-lipid metabolic disturbance in pre-diabetes accompanied with obesity.


Asunto(s)
Diabetes Mellitus Experimental , Resistencia a la Insulina , Estado Prediabético , Masculino , Ratones , Animales , Glucosa/metabolismo , Insulina/metabolismo , Estado Prediabético/tratamiento farmacológico , Ratones Obesos , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Espectrometría de Masas en Tándem , Ratones Endogámicos C57BL , Flavonoides/uso terapéutico , Transducción de Señal , Hígado , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Dexametasona/farmacología , Dieta Alta en Grasa/efectos adversos
3.
Molecules ; 28(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36770712

RESUMEN

The tuberous root of Ophiopogon japonicus (Thunb.) Ker-Gawl. is a well-known Chinese medicine also called Maidong (MD) in Chinese. It could be divided into "Chuanmaidong" (CMD) and "Zhemaidong" (ZMD), according to the geographic origins. Meanwhile, the root of Liriope spicata (Thunb.) Lour. var. prolifera Y. T. Ma (SMD) is occasionally used as a substitute for MD in the market. In this study, a reliable pressurized liquid extraction and HPLC-DAD-ELSD method was developed for the simultaneous determination of nine chemical components, including four steroidal saponins (ophiopojaponin C, ophiopogonin D, liriopesides B and ophiopogonin D'), four homoisoflavonoids (methylophiopogonone A, methylophiopogonone B, methylophiopogonanone A and methylophiopogonanone B) and one sapogenin (ruscogenin) in CMD, ZMD and SMD. The method was validated in terms of linearity, sensitivity, precision, repeatability and accuracy, and then applied to the real samples from different origins. The results indicated that there were significant differences in the contents of the investigated compounds in CMD, ZMD and SMD. Ruscogenin was not detected in all the samples, and liriopesides B was only found in SMD samples. CMD contained higher ophiopogonin D and ophiopogonin D', while the other compounds were more abundant in ZMD. Moreover, the anticancer effects of the herbal extracts and selected components against A2780 human ovarian cancer cells were also compared. CMD and ZMD showed similar cytotoxic effects, which were stronger than those of SMD. The effects of MD may be due to the significant anticancer potential of ophiopognin D' and homoisoflavonoids. These results suggested that there were great differences in the chemical composition and pharmacological activity among CMD, ZMD and SMD; thus, their origins should be carefully considered in clinical application.


Asunto(s)
Medicamentos Herbarios Chinos , Ophiopogon , Neoplasias Ováricas , Saponinas , Compuestos de Espiro , Humanos , Femenino , Ophiopogon/química , Línea Celular Tumoral , Saponinas/farmacología , Saponinas/química , Medicamentos Herbarios Chinos/química
4.
J Nanobiotechnology ; 21(1): 57, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36803772

RESUMEN

BACKGROUND: Globally, millions of patients suffer from regenerative deficiencies, such as refractory wound healing, which is characterized by excessive inflammation and abnormal angiogenesis. Growth factors and stem cells are currently employed to accelerate tissue repair and regeneration; however, they are complex and costly. Thus, the exploration of new regeneration accelerators is of considerable medical interest. This study developed a plain nanoparticle that accelerates tissue regeneration with the involvement of angiogenesis and inflammatory regulation. METHODS: Grey selenium and sublimed sulphur were thermalized in PEG-200 and isothermally recrystallised to composite nanoparticles (Nano-Se@S). The tissue regeneration accelerating activities of Nano-Se@S were evaluated in mice, zebrafish, chick embryos, and human cells. Transcriptomic analysis was performed to investigate the potential mechanisms involved during tissue regeneration. RESULTS: Through the cooperation of sulphur, which is inert to tissue regeneration, Nano-Se@S demonstrated improved tissue regeneration acceleration activity compared to Nano-Se. Transcriptome analysis revealed that Nano-Se@S improved biosynthesis and ROS scavenging but suppressed inflammation. The ROS scavenging and angiogenesis-promoting activities of Nano-Se@S were further confirmed in transgenic zebrafish and chick embryos. Interestingly, we found that Nano-Se@S recruits leukocytes to the wound surface at the early stage of regeneration, which contributes to sterilization during regeneration. CONCLUSION: Our study highlights Nano-Se@S as a tissue regeneration accelerator, and Nano-Se@S may provide new inspiration for therapeutics for regenerative-deficient diseases.


Asunto(s)
Nanocompuestos , Nanopartículas , Selenio , Embrión de Pollo , Humanos , Ratones , Animales , Selenio/farmacología , Selenio/química , Pez Cebra/metabolismo , Especies Reactivas de Oxígeno , Cicatrización de Heridas , Nanopartículas/química , Inflamación , Azufre
5.
Phytomedicine ; 113: 154718, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36854203

RESUMEN

BACKGROUND: Ophiopogon japonicus (Thunb.) Ker Gawl., a well-known Chinese herb, has been used in traditional Chinese medicine for thousands of years. Extensive in vitro and in vivo studies have shown that O. japonicus and its active compounds exhibit potential anticancer effects in a variety of cancer cells in vitro and suppress tumor growth and metastasis without causing serious toxicity in vivo. PURPOSE: This review aims to systemically summarize and discuss the anticancer effects and the underlying mechanisms of O. japonicus extracts and its active compounds. METHODS: The review is prepared following the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Various scientific databases including Web of Science, PubMed, Scopus, and Chinese National Knowledge Infrastructure were searched using the keywords: Ophiopogon japonicus, tumor, cancer, carcinoma, content, pharmacokinetics, and toxicity. RESULTS: O. japonicus extracts and the active compounds, such as ruscogenin-1-O-[ß-d-glucopyranosyl(1→2)][ß-d-xylopyranosyl(1→3)]-ß-d-fucopyranoside (DT-13), ophiopogonin B, and ophiopogonin D, exert potential anticancer effects, including the induction of cell cycle arrest, activation of apoptosis and autophagy, and inhibition of metastasis and angiogenesis. In addition, the mechanisms underlying these effects, as well as the pharmacokinetics, toxicity and clinical utility of O. japonicus extracts and active compounds are discussed. Furthermore, this review highlights the research and application prospects of these compounds in immunotherapy and combination chemotherapy. CONCLUSIONS: The traditional herb O. japonicus and its phytochemicals could be safe and reliable anticancer drug candidates, alone or in combination with chemotherapeutic drugs. We hope that this review, which highlights the anticancer properties of O. japonicus, will contribute to drug optimization, therapeutic development, and future studies on cancer therapies based on this medicinal plant.


Asunto(s)
Medicamentos Herbarios Chinos , Ophiopogon , Medicamentos Herbarios Chinos/química , Ophiopogon/química , Medicina Tradicional China , Fitoquímicos
6.
J Control Release ; 353: 752-766, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36526020

RESUMEN

The combination of excessive reactive oxygen species (ROS) levels, neuroinflammation, and pathogenic protein aggregation disrupt the homeostasis of brain microenvironment, creating conditions conducive to the progression of Parkinson's disease (PD). Restoring homeostasis by remodeling the brain microenvironment could reverse this complex pathological progression. However, treatment strategies that can induce this effect are currently unavailable. Herein, we developed a "Swiss Army Knife" nanodelivery platform consisting of matrine (MT) and polyethylene glycol-modified black phosphorus nanosheets (BP) that enables PD treatment by restoring brain microenvironment homeostasis. Under NIR irradiation, the photothermal effect induced by BP allowed the nanomedicine to cross the blood-brain barrier (BBB) and entered the brain parenchyma. In PD brains, the biological effects of BP and MT resulted in the removal of excess ROS, effective reduction of neuroinflammation, decreased aggregation of pathogenic proteins, and improved neurotransmitter delivery, eventually restoring dopamine levels in the striatum. This study demonstrated the effective capacity of a BP-based nanodelivery platform to enter the brain parenchyma and trigger multiple neuropathological changes in PD brains. The platform serves as a safe and effective anti-PD nanomedicine with immense clinical potential.


Asunto(s)
Enfermedad de Parkinson , Fósforo , Humanos , Especies Reactivas de Oxígeno , Enfermedades Neuroinflamatorias , Encéfalo/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Antiparkinsonianos/uso terapéutico
7.
Materials (Basel) ; 15(23)2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36499961

RESUMEN

Understanding the coupling between electrons and phonons in iron chalcogenides FeTexSe1-x has remained a critical but arduous project in recent decades. The direct observation of the electron-phonon coupling effect through electron dynamics and vibrational properties has been lacking. Here, we report the first pressure-dependent ultrafast photocarrier dynamics and Raman scattering studies on an iron chalcogenide FeTe0.5Se0.5 to explore the interaction between electrons and phonons in this unconventional superconductor. The lifetime of the excited electrons evidently decreases as the pressure increases from 0 to 2.2 GPa, and then increases with further compression. The vibrational properties of the A1g phonon mode exhibit similar behavior, with a pronounced frequency reduction appearing at approximately 2.3 GPa. The dual evidence reveals the enhanced electron-phonon coupling strength with pressure in FeTe0.5Se0.5. Our results give an insight into the role of the electron-phonon coupling effect in iron-based superconductors.

8.
ACS Cent Sci ; 8(9): 1336-1349, 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36188350

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the gradual loss of dopaminergic neurons in the substantia nigra and the accumulation of α-synuclein aggregates called Lewy bodies. Here, nanodecoys were designed from a rabies virus polypeptide with a 29 amino acid (RVG29)-modified red blood cell membrane (RBCm) to encapsulate curcumin nanocrystals (Cur-NCs), which could effectively protect dopaminergic neurons. The RVG29-RBCm/Cur-NCs nanodecoys effectively escaped from reticuloendothelial system (RES) uptake, enabled prolonged blood circulation, and enhanced blood-brain barrier (BBB) crossing after systemic administration. Cur-NCs loaded inside the nanodecoys exhibited the recovery of dopamine levels, inhibition of α-synuclein aggregation, and reversal of mitochondrial dysfunction in PD mice. These findings indicate the promising potential of biomimetic nanodecoys in treating PD and other neurodegenerative diseases.

9.
Front Pharmacol ; 13: 1017830, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36188550

RESUMEN

Ophiopogon japonicus (OJ) is a traditional Chinese herbal medicine that has been used for thousands of years. Recently, the anticancer effects of OJ have been reported in multiple types of cancer, particularly in lung cancer. However, the underlying mechanisms remain unclear. In present study, the effects of OJ against NCI-H1299 human lung cancer cells were investigated, and the underlying mechanisms were explored using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS)-based cell metabolomics. As a result, OJ inhibited the proliferation, induced the apoptosis and suppressed the migration of NCI-H1299 cells. A total of 22 differential metabolites responsible for the effects of OJ were screened and annotated based on the LC-MS-based cell metabolomics approach. The altered metabolites were involved in three metabolic pathways, including glycerophospholipid metabolism, ether lipid metabolism and glutathione metabolism. These results showed that cell metabolomics-based strategies are promising tools to discover the action mechanisms of OJ against lung cancer cells.

10.
Front Nutr ; 9: 887992, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35586734

RESUMEN

Monk fruit, also named Luo Han Guo, is the fruit of Siraitia grosvenorii (Swingle) C. Jeffrey ex A. M. Lu et Z. Y. Zhang and has been used as both food and traditional Chinese medicine. Due to preservation concerns, monk fruit is usually processed by hot-air drying or using low-temperature techniques after harvest. In this study, high-performance thin-layer chromatography (HPTLC) method was developed for the analysis of 13 mogrosides, 1 flavonoid, and 3 sugars in monk fruit products. Then chemometric analysis was applied to investigate the chemical characteristics in the samples dried by different methods. The results showed that the contents of mogroside V, 11-oxo-mogroside V, isomogroside V, and sucrose in monk fruits dried at low temperature were much higher than those in traditional hot-air drying samples, which was also confirmed by HPTLC-scanning. These findings indicate that HPTLC combined with chemometric analysis provides a reliable tool to understand the chemical differences between the monk fruit products processed by different drying methods, which will be helpful for their quality evaluation.

11.
Front Pharmacol ; 13: 857706, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35330825

RESUMEN

As a prevalent medicinal liquor among Chinese people, a type of Chinese herbal spirit from Jing Brand Co., Ltd (CHS-J) is a newly developed health beverage with the health functions of anti-fatigue and immune enhancement. The researchers from the enterprise found that the contents of several components in CHS-J samples have been significantly decreasing during the stated storage period, as detected by the HPLC-UV method, which would make a great challenge for quality control of CHS-J. Furthermore, the chemical stability of CHS-J during the storage period is greatly challenged affected, especially in the environment of high temperature and light exposure. To systematically reveal the unstable components and promote the quality control of CHS-J, the chemical stability of CHS-J during the shelving storage period was characterized by the UPLC/Q-TOFMS-based metabolomics approach. First, the targeted and untargeted metabolomics approaches discovered the significantly changed components in CHS-J samples produced in different years. Furthermore, the accelerated tests of newly produced CHS samples and several authorized standards were conducted to validate the above results and elucidate the possible mechanisms underlying these chemical changes. Moreover, these chemical changes during the storage period had little influence on the anti-fatigue effect of CHS-J samples. These findings will offer new insight into the understanding of the chemical stability of CHS-J and will facilitate the quality control of CHS-J.

12.
Chin Med ; 17(1): 29, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35193628

RESUMEN

Chinese herbal medicines (CHMs) have unique advantages in the prevention and treatment of diseases, which are widely recognized in the world. More and more CHMs are becoming increasingly popular in the international markets. However, the quality control of CHMs is a significant issue for their acceptance and recognition in the international market. This review mainly focuses on the quality requirements for CHMs to enter the European Union (EU) market. Both Chinese and European regulations and quality controls are compared. Firstly, the EU medicinal regulatory system and relevant regulations were reviewed. Secondly, the key factors of the quality control of CHMs, including Chinese herbal drugs, extracts and products were compared with those of European herbal medicines in the EU market. Subsequently, three main registration routes for herbal medicinal products including Chinese herbal medicinal products entering the EU were introduced. Furthermore, the legal status of traditional Chinese medicine granules in the EU was also discussed. Through the comparison of the key quality factors for CHMs in China and the EU, the similarities and differences in terms of quality requirements and regulations are addressed, which provides a reference for the development of CHMs into the EU market.

13.
Biomaterials ; 260: 120339, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32861017

RESUMEN

The treatment of Parkinson's disease (PD) is hampered by the blood-brain barrier (BBB). As such, there is an urgent need for the development of a novel nanoplatform capable of penetrating the BBB in order to effectively treat PD. In the present study, we utilized black phosphorus nanosheets (BP) containing the brain-targeting ligand lactoferrin (Lf) and loaded with Paeoniflorin (Pae) to obtain Lf-BP-Pae. Through an effective photo-thermal effect, these Lf-BP-Pae particles were capable of traversing the BBB and effectively treating PD in a targeted manner. Importantly, this BP-based nanoplatform was capable of achieving satisfactory biocompatibility and biosafety with excellent anti-Parkinsonian efficacy, making it ideal for clinical applications.


Asunto(s)
Nanopartículas , Nanoestructuras , Enfermedad de Parkinson , Barrera Hematoencefálica , Encéfalo , Sistemas de Liberación de Medicamentos , Humanos , Lactoferrina , Enfermedad de Parkinson/tratamiento farmacológico , Fósforo/uso terapéutico
14.
Chin Med ; 15: 76, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32742301

RESUMEN

Traditional Chinese medicine (TCM) are becoming more and more popular all over the world. However, quality issues of TCM may lead to medical incidents in practice and therefore quality control is essential to TCM. In this review, the state of TCM in European Pharmacopoeia are compared with that in Chinese Pharmacopoeia, and herbal drugs that are not considered as TCM and not elaborated by TCM working party at European Directorate for the Quality of Medicines & Health Care (EDQM) but present in both European Pharmacopoeia and Chinese Pharmacopoeias are also discussed. Different aspects in quality control of TCM including origins, identification, tests and assays, as well as sample preparation, marker selection and TCM processing are covered to address the importance of establishing comprehensive quality standard of TCM. Furthermore, advanced analytical techniques for quality control and standard establishment of TCM are also reviewed.

15.
ACS Appl Mater Interfaces ; 11(48): 45276-45289, 2019 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-31638771

RESUMEN

Recent work has highlighted the potential of puerarin (PU) as a valuable compound to treat Parkinson's disease (PD), but its undesirable water solubility and bioavailability have constrained its utility. In this study, we sought to develop nanoparticles (NPs) that could be used to encapsulate PU, thereby extending its in vivo half-life and improving its bioavailability and accumulation in the brain to treat the symptoms of PD. We prepared spherical NPs (88.36 ± 1.67 nm) from six-armed star-shaped poly(lactide-co-glycolide) (6-s-PLGA) NPs that were used to encapsulate PU (PU-NPs) with 89.52 ± 1.74% encapsulation efficiency, 42.97 ± 1.58% drug loading, and a 48 h sustained drug release. NP formation and drug loading were largely mediated by hydrophobic interactions, while changes in the external environment led these NPs to become increasingly hydrophilic, thereby leading to drug release. Relative to PU alone, PU-NPs exhibited significantly improved cellular internalization, permeation, and neuroprotective effects. Upon the basis of Förster resonance energy transfer (FRET) of NPs-administered zebrafish, we were able to determine that these NPs were rapidly absorbed into circulation whereupon they were able to access the brain. We further conducted oral PU-NPs administration to rats, revealing significant improvements in PU accumulation within the plasma and brain relative to rats administered free PU. In MPTP-mediated neurotoxicity in mice, we found that PU-NPs treatment improved disease-associated behavioral deficits and depletion of dopamine and its metabolites. These findings indicated that PU-NPs represent a potentially viable approach to enhancing PU oral absorption, thus improving its delivery to the brain wherein it can aid in the treatment of PD.


Asunto(s)
Encéfalo/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Medicamentos Herbarios Chinos/administración & dosificación , Isoflavonas/administración & dosificación , Enfermedad de Parkinson/tratamiento farmacológico , Administración Oral , Animales , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/instrumentación , Evaluación Preclínica de Medicamentos , Liberación de Fármacos , Medicamentos Herbarios Chinos/efectos adversos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacocinética , Femenino , Humanos , Isoflavonas/efectos adversos , Isoflavonas/química , Isoflavonas/farmacocinética , Masculino , Ratones , Ratones Endogámicos C57BL , Nanopartículas/química , Ratas , Ratas Sprague-Dawley , Pez Cebra
16.
Environ Pollut ; 255(Pt 1): 113157, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31541838

RESUMEN

As one of the highest energy consuming and polluting industries, the power generation industry is an important source of particulate matter emissions. Recently, implementation of ultra-low emission technology has changed the emission characteristic of fine particulate matter (PM2.5). In this study, PM2.5 emitted from four typical power plants in China was sampled using a dilution channel sampling system, and analyzed for elements, water-soluble ions and carbonaceous fractions. The results showed that PM2.5 concentrations emitted from the four power plants were 0.78 ±â€¯0.16, 0.63 ±â€¯0.09, 0.29 ±â€¯0.07 and 0.28 ±â€¯0.01 mg m-3, respectively. Emission factors were 0.004-0.005 g/kg coal, nearly 1-2 orders of magnitude lower than those reported in previous studies. The highest proportions of PM2.5 consisted of organic carbon (OC), SO42-, elemental carbon (EC), NH4+, Al and Cl-. Coefficients of divergence (CDs) were in the ranges 0.22-0.41 (for an individual plant), 0.43-0.69 (among different plants), and 0.60-0.99 (in previous studies). The results indicated that the source profiles of each tested power plant were relatively similar, but differed from those in previous studies. Enrichment factors showed elevated Se and Hg, in accordance with the source markers Se and As. Comparing source profiles with previous studies, the proportion of OC, EC and NH4+ were higher, while the proportion of Al in PM2.5 were relatively lower. The OC/EC ratio became concentrated at ∼5. Results from this study can be used for source apportionment and emission inventory calculations after implementation of ultra-low emission technologies.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Centrales Eléctricas , Aluminio/análisis , Arsénico/análisis , Carbono/análisis , China , Carbón Mineral/análisis , Mercurio/análisis , Selenio/análisis , Agua/química
17.
Environ Sci Pollut Res Int ; 26(23): 24305-24312, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31256395

RESUMEN

Identifying the sources of volatile organic compounds (VOCs) is key to air quality control and pollution prevention. Though receptor models have been widely used in source apportionment of VOCs, they are not applicable to identify the potential source of labile species. In this study, the potential source of methyl mercaptan (MeSH) near a large refining and petrochemical plant was identified using an indirect method. When wind directions were controlled, the study period was separated into two subperiods depending on the detection of MeSH. Relative contributions from potential sources were predicted by chemical mass balance model and positive matrix factorization model based on ambient concentrations of sulfur-free compounds. Both models predicted that petroleum refinery and petrochemical production were the dominant sources of VOCs in the study area. When MeSH was detected, the relative contribution from gasoline, liquefied petroleum gas, or crude oil increased by 7.4 to 26.8% point, depending on wind direction and the predictive model used, suggesting a close relationship between MeSH and the emission from petroleum refinery. Consistent with the indirect source apportionment, among the coexisting VOCs, MeSH was most highly correlated or associated with ethane, propane, isobutane, cis-2-pentente, and isoprene, which are major components of the products or by-products of petrochemical refining processes.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Modelos Químicos , Compuestos de Sulfhidrilo/análisis , Contaminación del Aire , Gasolina , Petróleo , Compuestos Orgánicos Volátiles/análisis , Viento
18.
Planta Med ; 85(11-12): 917-924, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31207650

RESUMEN

Ideally, metabolomics should deal with all the metabolites that are found within cells and biological systems. The most common technologies for metabolomics include mass spectrometry, and in most cases, hyphenated to chromatographic separations (liquid chromatography- or gas chromatography-mass spectrometry) and nuclear magnetic resonance spectroscopy. However, limitations such as low sensitivity and highly congested spectra in nuclear magnetic resonance spectroscopy and relatively low signal reproducibility in mass spectrometry impede the progression of these techniques from being universal metabolomics tools. These disadvantages are more notorious in studies of certain plant secondary metabolites, such as saponins, which are difficult to analyse, but have a great biological importance in organisms. In this study, high-performance thin-layer chromatography was used as a supplementary tool for metabolomics. A method consisting of coupling 1H nuclear magnetic resonance spectroscopy and high-performance thin-layer chromatography was applied to distinguish between Ophiopogon japonicus roots that were collected from two growth locations and were of different ages. The results allowed the root samples from the two growth locations to be clearly distinguished. The difficulties encountered in the identification of the marker compounds by 1H nuclear magnetic resonance spectroscopy was overcome using high-performance thin-layer chromatography to separate and isolate the compounds. The saponins, ophiojaponin C or ophiopogonin D, were found to be marker metabolites in the root samples and proved to be greatly influenced by plant growth location, but barely by age variation. The procedure used in this study is fully described with the purpose of making a valuable contribution to the quality control of saponin-rich herbal drugs using high-performance thin-layer chromatography as a supplementary analytical tool for metabolomics research.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Ophiopogon/metabolismo , Raíces de Plantas/metabolismo , Saponinas/metabolismo , Cromatografía en Capa Delgada/métodos , Espectroscopía de Resonancia Magnética , Metabolómica , Ophiopogon/química , Raíces de Plantas/química , Saponinas/análisis , Saponinas/química , Espirostanos/química
19.
Molecules ; 24(1)2018 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-30591651

RESUMEN

The emergence and development of two-dimensional (2D) materials has provided a new direction for enhancing the thermoelectric (TE) performance due to their unique structural, physical and chemical properties. However, the TE performance measurement of 2D materials is a long-standing challenge owing to the experimental difficulties of precise control in samples and high demand in apparatus. Until now, there is no universal methodology for measuring the dimensionless TE figure of merit (ZT) (the core parameter for evaluating TE performance) of 2D materials systematically in experiments. Raman spectroscopy, with its rapid and nondestructive properties for probing samples, is undoubtedly a powerful tool for characterizing 2D materials as it is known as a spectroscopic 'Swiss-Army Knife'. Raman spectroscopy can be employed to measure the thermal conductivity of 2D materials and expected to be a systematic method in evaluating TE performance, boosting the development of thermoelectricity. In this review, thermoelectricity, 2D materials, and Raman techniques, as well as thermal conductivity measurements of 2D materials by Raman spectroscopy are introduced. The prospects of obtaining ZT and testing the TE performance of 2D materials by Raman spectroscopy in the future are also discussed.


Asunto(s)
Electricidad , Ensayo de Materiales , Espectrometría Raman , Temperatura , Fósforo/química
20.
J Chromatogr A ; 1501: 39-50, 2017 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-28476319

RESUMEN

To meet the demands from plant physiologists and pharmacognosists, sustainable efforts are being devoted by the analytical chemists from all over the world to search an approach being capable of simultaneously monitoring primary along with secondary metabolites. The key technical bottlenecks currently lie at affording satisfactory chromatographic and spectrometric performances for both hydrophilic and hydrophobic substances that span a great content range. Herein, reverse phase liquid chromatography was directly coupled with hydrophilic interaction chromatography, namely RPLC-HILIC, to integrate their merits, whereas dilution pumps were employed to tackle the mismatching for the mobile phase between them. On the other side, inferior parameters rather than the optimal ones were applied for those abundant ingredients to advance the upper limits of quantitation, such as echinacoside (1250.0µg/mL), mannitol (100.0µg/mL), and acteoside (125µg/mL), in mass spectrometer domain. As a desert parasitic plant as well as tonic materials, Cistanche tubulosa (CT) has drawn widely interests from plant physiologists and pharmacognosists regarding its quantitative metabolome. Simultaneous determination of 23 abundant and minor ingredients covering most chemical families in CT, i.e. amino acid, nucleoside, organic acid, phenylethanoid glycoside, lignan, and iridoid, was attempted to understand the physiologic patterns as well as pharmacological values of the crude materials. Although the analytes spanned wide polarity (-3.326≤cLogP≤1.421) and content (more than 5 orders of magnitude) ranges, satisfactory chromatographic and spectrometric behaviors were gained for all analytes. Reliable quantitation was demonstrated via various method validation assays, such as recovery, linearity, sensitivity, and precision. The contents of 23 hydrophilic and hydrophobic substances were quantified in 20 batches of CT. Significant variations occurred for the contents of those components. Echinacoside (1.35-387.50mg/g) was usually observed as the most abundant component, whereas ferulic acid (<0.0043mg/g) always exhibited trace distributions. Above all, the integrated equipment setup could serve as a fit-for-purpose tool for in-depth quality evaluation of CT and more importantly, for comprehensively understanding the metabolome of plants.


Asunto(s)
Cromatografía de Fase Inversa/métodos , Cistanche/química , Extractos Vegetales/química , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos , Glucósidos/análisis , Glicósidos/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Metaboloma , Nucleósidos , Fenoles/análisis
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