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1.
RSC Adv ; 14(9): 6064-6071, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38370457

RESUMO

In petroleum, petrochemicals, metallurgy, and chemical industries, a significant volume of oily wastewater is unavoidably generated throughout the production processes. This not only harms the environment but also brings about diverse adverse effects on social and economic progress. In this study, copper mesh separation membranes exhibiting superhydrophobicity and superhydrophilicity/underwater superoleophobicity were fabricated through in situ oxidation, chemical vapor deposition, and other physical and chemical modification techniques. Moreover, copper meshes possessing contrasting wetting properties were incorporated into a system combining superhydrophilicity and superhydrophobicity enabling the continuous and efficient separation of mixed oil-water liquids. The separation efficiency of both the superhydrophobic and superhydrophilic membranes surpassed 99.0% and remained above 97.0% after 15 days of continuous use, showcasing the remarkable effectiveness and durability of the integrated system design. This research presents a straightforward and cost-effective design approach for the large-scale treatment of oily wastewater in industrial settings, which is expected to have extensive applications in practical production.

2.
Chem Sci ; 15(4): 1260-1270, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38274075

RESUMO

[4 + 2] cycloaddition has led to diverse polycyclic chiral architectures, serving as novel sources for organic synthesis and biological exploration. Here, an unprecedented class of cadinane sesquiterpene [4 + 2] dimers, henryinins A-E (1-5), with a unique 6/6/6/6/6-fused pentacyclic system, were isolated from Schisandra henryi. The divergent total syntheses of compounds 1-5 and their enantiomers (6-10) were concisely accomplished in eight linear steps using a protection-free approach. Mechanistic studies illustrated the origin of selectivity in the key [4 + 2] cycloaddition as well as the inhibition of reaction pathway bifurcation via desymmetrization. The chemical proteomics results showed that a pair of enantiomers shared common targets (PRDX5 C100 and BLMH C73) and had unique targets (USP45 C588 for 4 and COG7 C419 for 9). This work provides experimental evidence for the discovery of unprecedented cadinane dimers from selective Diels-Alder reaction and a powerful strategy to explore the biological properties of natural products.

3.
Chem Commun (Camb) ; 58(82): 11488-11506, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36165339

RESUMO

Metal-organic frameworks (MOFs) possess excellent advantages, such as high porosity, large specific surface area, and an adjustable structure, showing good potential for applications in gas adsorption and separation, catalysis, conductivity, sensing, magnetism, etc. However, they still suffer from significant limitations in terms of the scale-up synthesis and shaping, hindering the realization of large-scale commercial applications. Despite some attempts having been devoted to addressing this, challenges remain. In this paper, we outline the advantages and drawbacks of existing synthetic routes such as electrochemistry, microwave, ultrasonic radiation, green solvent reflux, room temperature stirring, steam-assisted transformation, mechanochemistry, and fluid chemistry in terms of scale-up production. Then, the shaping methods of MOFs such as extrusion, mechanical compaction, rolling granulation, spray drying, gel technology, embedded granulation, phase inversion, 3D printing and other shaping methods for the preparation of membranes, coatings and nanoparticles are discussed. Finally, perspectives on the large-scale synthesis and shaping of MOFs are also proposed. This work helps provide in-depth insight into the scale-up production and shaping process of MOFs and boost commercial applications of MOFs.

4.
Int J Biol Macromol ; 213: 328-338, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35594938

RESUMO

To explore the active polysaccharides from Dendrobium devonianum, a novel O-acetylmannan (DDP-1) with molecular weight of 117 kDa was isolated from D. devonianum. The chemical and instrumental analysis indicated that the DDP-1 was a homopolysaccharide containing a backbone chain composed of →4)-ß-d-Manp-(1 â†’ (71.4%) residue with internal →4)-2-O-acetyl-ß-d-Manp-(1 â†’ (14.2%), →4)-3-O-acetyl-ß-d-Manp-(1 â†’ (7.1%), and non-reducing end ß-d-Manp-(1 â†’ (7.3%) residues. Anticancer assay in vitro revealed that DDP-1 had anticancer activity against the growth of HepG2 and MCF-7 cancer cells. Moreover, cytokine secretion assays also presented that DDP-1 can promote cytokine production of TNF-α and IL-6 in THP-1 macrophage stimulated by PMA. Finally, the effects of isolation and purification on the microstructure of DDP-1 was studied by scanning electron microscope. The morphological features of DDP-1 indicated that DDP-1 hold high potential application in hydrophilic polymer materials.


Assuntos
Dendrobium , Citocinas , Dendrobium/química , Mananas/farmacologia , Polímeros , Polissacarídeos/química
5.
Phytochemistry ; 182: 112589, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33352309

RESUMO

Schipropins A-J, a series of undescribed lanostane and cycloartane-type triterpenoids, were isolated from the stems and leaves of Schisandra propinqua. Their structures, most of which were characterized by C-3/C-4 cleavage, were elucidated by extensive spectroscopic analyses. Noteworthily, the absolute configurations of schipropins A, D-G, and I were determined by single-crystal X-ray diffraction. Furthermore, schipropins E and G were found to possess moderate NO production inhibitory activity.


Assuntos
Schisandra , Triterpenos , Cristalografia por Raios X , Estrutura Molecular , Folhas de Planta
6.
Bioorg Chem ; 105: 104353, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33096311

RESUMO

Eleven undescribed schinortriterpenoids (SNTs) and one known analogue (12) were isolated from the stems and leaves of Schisandra henryi. Their diverse structures included preschisanartane (1), 18-norschiartane (2-5, 12), schiartane (6 and 7), and schisanartane (8-11) skeletons, which were elucidated by comprehensive NMR, MS, electronic circular dichroism analyses, single crystal X-ray diffraction and biogenetic considerations. 1 was the first case of preschisanartane-type SNT with six-membered lactone ring, and 2 was one of the most highly oxygenated 18-norschiartane SNTs. Three types of the highly oxygenated SNTs, 1, 4, 10 and 11, effectively prevent apoptosis induced by corticosterone in PC12 cells. In addition, 11 showed neurite outgrowth-promoting activity.


Assuntos
Fármacos Neuroprotetores/química , Extratos Vegetais/química , Folhas de Planta/química , Caules de Planta/química , Schisandra/química , Triterpenos/química , Animais , Corticosterona/metabolismo , Avaliação Pré-Clínica de Medicamentos , Humanos , Lactonas/química , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Oxigênio/química , Células PC12 , Ratos , Triterpenos/farmacologia
7.
Front Pharmacol ; 10: 1128, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632272

RESUMO

Naoxintong capsule (NXT), a Chinese medicine, has performed excellent effects on the prevention and treatment against cardiovascular diseases. NXT is a fine powder mixture without any herb extraction, and there must be lots of ingredients hard to be absorbed. However, little is known about the correlation between the NXT's cardioprotective effects and gut microbiota. Herein, we report the effect of NXT on the development of cardiovascular diseases and clarify the correlation between NXT's cardioprotective effects and gut microbiota. In the current study, minipigs were selected and fed with high-fat diet and NXT daily for successive 8 months. During the process, up to 18 biomedical parameters were monthly determined to observe the dynamic changes after NXT treatment. At the end of experimental process, pathological examinations of heart, coronary artery, carotid artery, thoracic aorta, and abdominal aorta were conducted by HE staining and 16SrDNA sequencing, and analyzing of gut microbiota were conducted. Our results showed that NXT's effects against cardiovascular diseases were through regulating blood lipid profiles, inhibiting vascular inflammation, enhancing antioxidant capacity, and alleviating myocardial injury, without damages on liver and kidney particularly. Concurrently, we also found that long-term administration of NXT increased the diversity of gut microbiota, influenced the microbiome structure and composition stably, and revered the increase of the ratio of the Firmicutes to Bacteroidetes (F/B ratio) in relative abundance. Specifically, our results revealed some key bacterium of Caproiciproducens (enhanced), Sutterella (enhanced), Erysipelotrichaceae (enhanced), and Romboutsia (decreased) that were closely involved in NXT's effects. Taken together, our study demonstrates that NXT can inhibit the development of cardiovascular diseases by ameliorating high-fat diet-induced metabolic disorders and partly through improving gut microbiota.

8.
Molecules ; 23(10)2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30332800

RESUMO

2,3-O-acetylated-1,4-ß-d-glucomannan (DOP-1-1) is a polysaccharide isolated from the stem of Dendrobium officinale. DOP-1-1 has been demonstrated to have remarkable immunomodulatory properties, but little is known about the influence of its structural diversity on bioactivity (and even less about the exact mechanism underlying its immune responses). First, DOP-1-1 was stabilized at different temperatures and pH conditions based on differential scanning calorimetry and size exclusion-chromatography⁻high-performance liquid chromatography. Then, a detailed study on the effects of DOP-1-1 on a human leukemia monocytic cell line (THP-1) under normal conditions was undertaken. DOP-1-1 promoted the translocation of nuclear factor-kappa B (NF-κB) and degradation of IκB proteins. The expression of genes and proteins closely associated with the immune, survival and apoptotic functions of NF-κB were analyzed by quantitative real-time RT-PCR. Furthermore, CCL4 and IP10 were confirmed to be the novel targets of the immune response stimulated by DOP-1-1. The phosphorylation of NF-кB was inhibited by treatment with a toll-like receptor 4 (TLR4) antagonist (TAK-242) and myeloid differentiation factor 88 (MyD88) inhibitor (ST2825). These data suggested: (i) the O-acetylated glucomannan DOP-1-1 is present in the steady state in low-pH solutions; (ii) DOP-1-1 can induce an immune response through NF-кB mediated by a TLR4 signaling pathway; and (iii) CCL4 and IP10 could be the novel targets of the immune response stimulated by O-acetylated glucomannan.


Assuntos
Dendrobium/química , Imunidade/efeitos dos fármacos , Mananas/farmacologia , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Acetilação , Varredura Diferencial de Calorimetria , Quimiocina CCL4/genética , Quimiocina CCL4/metabolismo , Cromatografia em Gel , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mananas/química , Estrutura Molecular , Fosforilação/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Transporte Proteico/efeitos dos fármacos , Células THP-1
9.
Exp Biol Med (Maywood) ; 243(5): 481-495, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29444597

RESUMO

Currently, the prevention and treatment of hypertensive crises especially when it occurs with serious adverse outcomes have led to worldwide controversy. Despite of clinical possibilities of multiple agents, clinical failures still occur frequently. Therefore, early evaluations and observations of different therapies on appropriate animals should be emphasized. In the present study, an animal model for hypertensive crises emergencies was firstly established and experimentally testified. Five-month-male spontaneously hypertensive rat was consecutively fed with 60%-Kcal fat diet for four, six, and eight weeks with body weight and blood pressure monitored every two weeks, and then followed by an acute vasoconstriction stress of 5-min ice-bath treatment in the 4-h time interval of two adrenaline injections (0.8 mg/kg). Forty-four biochemical parameters were detected, covering hepatic and renal function, blood glucose and lipid levels, myocardial enzymes and energy metabolisms, blood coagulative and anti-coagulative system, oxidative stress and anti-inflammatory cytokine, blood viscosity, and RAAS system. Six tissues including heart, brain, liver, kidney, coronary arteries, and mesenteries were removed for pathological observations with hematoxylin-eosin staining. As a result, multi-organ dysfunctions in the heart, brain, liver, kidney, vascular endothelium, and blood system were testified in the modeling rats at weeks 6 and 8. In conclusion, severe consequences of this animal model were highly similar to those in hypertensive crises emergencies, which could be further utilized in the early intervention of hypertensive crises emergencies including the possible risk factors control and efficient therapies assessment. Impact statement In the late 90s, numerous reports predicted that 1-2% of hypertensive individuals would undergo hypertensive crises (HPC) and figures reached as high as 7% when no antihypertensive therapies were administrated. Currently, clinical failures appear frequently due to the improper or excessive medication regimen instead of the illness itself. Therefore, early evaluations and observations of HPC on appropriate animal models ahead of patients should be discussed and emphasized more widely. In the present study, an appropriate animal model for HPC emergencies was firstly established, in which the consequences of long-term high-fat diet feeding followed by an acute vasoconstriction stress on the spontaneously hypertensive rats were experimentally testified. The proposed model would have a wide application prospects in early intervention of HPC emergencies including the controls of possible risk factors and assessments of efficient therapies.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Coração/fisiopatologia , Hipertensão/patologia , Rim/patologia , Vasoconstrição/fisiologia , Animais , Glicemia/análise , Pressão Sanguínea/fisiologia , Peso Corporal , Citocinas/sangue , Modelos Animais de Doenças , Endotélio Vascular/fisiopatologia , Lipídeos/sangue , Masculino , Estresse Oxidativo/fisiologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Fatores de Risco
10.
Int J Biol Macromol ; 112: 126-133, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29366898

RESUMO

A novel arabinogalactan (MOP-1) was isolated from leaves of Moringa oleifera and was purified by macro-porous resin, DEAE-52 Cellulose and Sepharose 6B gel filtration chromatography. High performance gel permeation chromatography (HPGPC) analysis showed that the molecular weight of MOP-1 was 7.65 × 107 Da. Monosaccharide composition analysis indicated that sugar composition is Rha: Ara: Gal in a molar ratio of 1:7.32:12.12. Structural analysis indicated that MOP-1 has a backbone of →1)-ß-d-Galp-(3,4→ with highly branched chains at O-4 position. The branches were composed of →1)-ß-d-Galp-(4→, →1)-α-d-Galp-(2→, Araf-(1→, Galp-(1→. Its antioxidant activities were evaluated by DPPH radical scavenging capacity, 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radical cation scavenging capacity, and ferric-reducing antioxidant power (FRAP). The results indicated MOP-1 exhibited significant antioxidant activities.


Assuntos
Antioxidantes/química , Sequestradores de Radicais Livres/química , Galactanos/química , Moringa oleifera/química , Antioxidantes/isolamento & purificação , Benzotiazóis/química , Sequestradores de Radicais Livres/isolamento & purificação , Galactanos/isolamento & purificação , Peso Molecular , Monossacarídeos/química , Monossacarídeos/isolamento & purificação , Folhas de Planta/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Ácidos Sulfônicos/química
11.
Int J Biol Macromol ; 83: 34-41, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26592697

RESUMO

A neutral heteropolysaccharide (DOP-1-1) consisted by mannose and glucose (5.9:1) with an average molecular weight at about 1.78×10(5) Da was purified from Dendrobium officinale. Based on Fourier transform infrared spectrum (FT-IR) and nuclear magnetic resonance (NMR) spectra, it suggested that partial structure of DOP-1-1 is an O-acetylated glucomannan with ß-d configuration in pyranose sugar forms. The immunomodulatory activity of DOP-1-1 was evaluated by secretion level of cytokine (interleukin (IL)-1ß and IL-10) and tumor necrosis factor (TNF)-α in vitro. Our results suggested that DOP-1-1 could stimulate cytokine production (TNF-α, IL-1ß) in cells. These findings demonstrated that the purified polysaccharide from D. officinale presented significant immune-modulating activities. Furthermore, by Western-blot we can found that the signaling pathways of DOP-1-1 induced immune activities involving ERK1/2 and NF-кB. As to antioxidant activity, DOP-1-1 hadn't showed remarkable scavenging capacity of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in contrast with other studies of polysaccharides from D. officinale.


Assuntos
Dendrobium/química , Imunomodulação/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo/farmacologia , Células Cultivadas , Humanos , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Manose/metabolismo , Picratos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Fator de Necrose Tumoral alfa/metabolismo
12.
J Org Chem ; 69(13): 4330-5, 2004 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-15202886

RESUMO

A new palladium catalyst (DAPCy) made from Pd(OAc)(2) and commercially available, inexpensive dicyclohexylamine has been developed for the Suzuki coupling reaction of aryl bromides with boronic acids to give the coupling products in good to high yields. The air-stable catalyst was characterized and well-defined by X-ray crystallography. A catalytic system involving DAPCy in dioxane demonstrates a temperature-dependent reactivity toward aryl bromides with different electronic substituents, and selectively couples electron-deficient aryl bromides with boronic acids over electron-rich ones at room temperature. Another catalytic system employing DAPCy in EtOH provides a general and convenient method to prepare biaryls from aryl bromides and boronic acids with a broad range of functional groups at room temperature and under aerobic conditions.


Assuntos
Aminas/química , Hidrocarbonetos Aromáticos/síntese química , Hidrocarbonetos Bromados/síntese química , Paládio/química , Ácidos Borônicos/química , Catálise , Ligantes , Modelos Moleculares , Estrutura Molecular
13.
J Med Chem ; 46(6): 1041-8, 2003 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-12620080

RESUMO

A series of conformationally restricted congeners of pentamidine in which the flexible pentyl bridge of pentamidine was replaced by trans-1,2-bismethylenecyclopropyl, phenyl, pyridinyl, piperazinyl, homopiperazinyl, and piperidinyl groups were synthesized. The compounds were evaluated for trypanocidal activity in vitro and in vivo against one drug-sensitive and three drug-resistant trypanosome isolates. The DNA binding affinity of the compounds was also studied using calf thymus DNA and poly(dA-dT). The nature of the linker influenced the DNA binding affinity as well as the trypanocidal activity of the compounds. trans-1,2-Bis(4-amidinophenoxymethylene)cyclopropane (1) was over 25-fold more potent than pentamidine against the drug-resistant isolate KETRI 243As-10-3, albeit with comparable DNA binding affinity. N,N'-Bis(4-amidinophenyl)homopiperazine (8) was the most potent trypanocide in vitro against all four trypanosome isolates studied, but N,N'-bis(4-amidinophenyl)piperazine (6) was the most effective agent in vivo against both drug-sensitive and drug-resistant trypanosomes.


Assuntos
Amidinas/síntese química , Pentamidina/análogos & derivados , Pentamidina/síntese química , Piperazinas/síntese química , Tripanossomicidas/síntese química , Amidinas/farmacologia , Animais , Cátions , Bovinos , DNA/química , Resistência a Medicamentos , Feminino , Camundongos , Conformação Molecular , Pentamidina/farmacologia , Piperazinas/farmacologia , Poli dA-dT/química , Relação Estrutura-Atividade , Tripanossomicidas/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Trypanosoma brucei rhodesiense/efeitos dos fármacos , Tripanossomíase/tratamento farmacológico
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