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The application of ozone (O3) disinfection has been hindered by its low solubility in water and the formation of disinfection by-products (DBPs). In this study, capacitive disinfection is applied as a pre-treatment for O3 oxidation, in which manganese dioxide with a rambutan-like hollow spherical structure is used as the electrode to increase the charge density on the electrode surface. When a voltage is applied, the negative-charged microbes are attracted to the electrodes and killed by electrical interactions. The contact between microbes and capacitive electrodes leads to changes in cell permeability and burst of reactive oxygen species, thereby promoting the diffusion of O3 into the cells. After O3 penetrates the cell membrane, it can directly attack the cytoplasmic constituents, accelerating fatal and irreversible damage to pathogens. As a result, the performance of the capacitance-O3 process is proved better than the direct sum of the two individual process efficiencies. The design of capacitance-O3 system is beneficial to reduce the ozone dosage and DBPs with a broader inactivation spectrum, which is conducive to the application of ozone in primary water disinfection.
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Desinfecção , Compostos de Manganês , Óxidos , Ozônio , Ozônio/farmacologia , Ozônio/química , Óxidos/farmacologia , Óxidos/química , Desinfecção/métodos , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Membrana Celular/efeitos dos fármacos , Purificação da Água/métodos , Eletrodos , Bactérias/efeitos dos fármacosRESUMO
The advancement of atomically precise dinuclear heterogeneous catalysts holds great potential in achieving efficient catalytic ozonation performance and contributes to the understanding of synergy mechanisms during reaction conditions. Herein, we demonstrate a "ship-in-a-bottle and pyrolysis" strategy that utilizes Fe2(CO)9 dinuclear-cluster to precisely construct Fe2 site, consisting of two Fe1-N3 units connected by Fe-Fe bonds and firmly bonded to N-doped carbon. Systematic characterizations and theoretical modeling reveal that the Fe-Fe coordination motif markedly reduced the devotion of the antibonding state in the Fe-O bond because of the strong orbital coupling interaction of dual Fe d-d orbitals. This facilitates O-O covalent bond cleavage of O3 and enhances binding strength with reaction intermediates (atomic oxygen species; *O and *OO), thus boosting catalytic ozonation performance. As a result, Fe dinuclear site catalyst exhibits 100% ozonation efficiency for CH3SH elimination, outperforming commercial MnO2 catalysts by 1,200-fold. This research provides insights into the atomic-level structure-activity relationship of ozonation catalysts and extends the use of dinuclear catalysts in catalytic ozonation and beyond.
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Carbon-defect engineering in single-atom metal-nitrogen-carbon (MâNâC) catalysts by straightforward and robust strategy, enhancing their catalytic activity for volatile organic compounds, and uncovering the carbon vacancy-catalytic activity relationship are meaningful but challenging. In this study, an iron-nitrogen-carbon (FeâNâC) catalyst is intentionally designed through a carbon-thermal-diffusion strategy, exposing extensively the carbon-defective FeâN4 sites within a micro-mesoporous carbon matrix. The optimization of FeâN4 sites results in exceptional catalytic ozonation efficiency, surpassing that of intact FeâN4 sites and commercial MnO2 by 10 and 312 times, respectively. Theoretical calculations and experimental data demonstrated that carbon-defect engineering induces selective cleavage of CâN bond neighboring the FeâN4 motif. This induces an increase in non-uniform charges and Fermi density, leading to elevated energy levels at the center of Fe d-band. Compared to the intact atomic configuration, carbon-defective FeâN4 site is more activated to strengthen the interaction with O3 and weaken the OâO bond, thereby reducing the barriers for highly active surface atomic oxygen (*O/*OO), ultimately achieving efficient oxidation of CH3SH and its intermediates. This research not only offers a viable approach to enhance the catalytic ozonation activity of MâNâC but also advances the fundamental comprehension of how periphery carbon environment influences the characteristics and efficacy of MâN4 sites.
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Electrocatalytic nitrogen reduction technology seamlessly aligns with the principles of environmentally friendly chemical production. In this paper, a comprehensive review of recent advancements in electrocatalytic NH3 synthesis utilizing single-atom catalysts (SACs) is offered. Into the research and applications of three categories of SACs: noble metals (Ru, Au, Rh, Ag), transition metals (Fe, Mo, Cr, Co, Sn, Y, Nb), and nonmetallic catalysts (B) in the context of electrocatalytic ammonia synthesis is delved. In-depth insights into the material preparation methods, single-atom coordination patterns, and the characteristics of the nitrogen reduction reaction (NRR) are provided. The systematic comparison of the nitrogen reduction capabilities of various SAC types offers a comprehensive research framework for their integration into electrocatalytic NRR. Additionally, the challenges, potential solutions, and future prospects of incorporating SACs into electrocatalytic nitrogen reduction endeavors are discussed.
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The design of a micro-/nanoreactor is of great significance for catalytic ozonation, which can achieve effective mass transfer and expose powerful reaction species. Herein, the mesoporous carbon with atomic Fe-N4 sites embedded in the ordered carbon nanochannels (Fe-N4/CMK-3) was synthesized by the hard-template method. Fe-N4/CMK-3 can be employed as nanoreactors with preferred electronic and geometric catalytic microenvironments for the internal catalytic ozonation of CH3SH. During the CH3SH oxidation process, the mass transfer coefficient of the Fe-N4/CMK-3 confined system with sufficient O3 transfer featured a level of at least 1.87 × 10-5, which is 34.6 times that of the Fe-N4/C-Si unconfined system. Detailed experimental studies and theoretical calculations demonstrated that the anchored atomic Fe-N4 sites and nanoconfinement effects regulated the local electronic structure of the catalyst and promoted the activation of O3 molecules to produce atomic oxygen species (AOS) and reactive oxygen species (ROS), eventually achieving efficient oxidation of CH3SH into CO2/SO42-. Benefiting from the high diffusion rate and the augmentation of AOS/ROS, Fe-N4/CMK-3 exhibited an excellent poisoning tolerance, along with high catalytic durability. This contribution provides the proof-of-concept strategy for accelerating catalytic ozonation of sulfur-containing volatile organic compounds (VOCs) by combining confined catalysis and atomic catalysts and can be extended to the purification of other gaseous pollutants.
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Carbono , Ozônio , Espécies Reativas de Oxigênio , Catálise , NanotecnologiaRESUMO
Dried ginger, a well-known medicine and food homologous production, has been widely circulated in China with high health benefits and economic value. Currently, there is still a lack of quality assessment on whether dried ginger in China exhibits chemically and biologically distinct properties, which creates a barrier to its quality control in commercial circulation. In this study, the chemical characteristics of 34 batches of common dried ginger samples in China were first explored using non-targeted chemometrics based on the UPLC-Q/TOF-MS analysis, leading to the identification of 35 chemicals that contributed to clustering into two categories, with sulfonated conjugates being the key chemically distinct components. By comparing the samples before and after sulfur-containing treatment and the further synthesis of a key differentiating component of [6]-gingesulfonic acid, it was then demonstrated that sulfur-containing treatment was the primary cause of the formation of sulfonated conjugates, as opposed to regional or environmental factors. Furthermore, the anti-inflammatory efficacy of dried ginger with high presence of sulfonated conjugates was significantly decreased. Consequently, for the first time, UPLC-QqQ-MS/MS was used to develop a targeted quantification method for 10 characteristic chemicals in dried ginger, allowing researchers to quickly determine whether dried ginger has been processed with sulfur and quantitatively evaluate the quality of dried ginger. These results provided an insight into the quality of commercial dried ginger in China and a suggested method for its quality supervision as well.
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Zingiber officinale , Zingiber officinale/química , Espectrometria de Massas em Tandem , Anti-Inflamatórios/farmacologia , China , EnxofreRESUMO
A new multifactor analysis assessment strategy was developed for evaluating, optimizing, and comparing analytical techniques for acrylamide in frying oils. Based on five indices (absolute recovery, absolute matrix effect, the intensity of the full ion scan, and the precursor ion scan to m/z 184 and m/z 241), the proposed strategy was performed with radar analysis, relative contribution analysis, and the entropy-weighted technique for order performance by similarity to ideal solution analysis. Two novel methods based on quick, easy, cheap, effective, rugged, and safe extraction methodology and gel permeation chromatography-liquid-liquid extraction followed by liquid chromatography-tandem mass spectrometry have been developed for the analysis of acrylamide in frying oils. Two methods were suitable for rapid and sensitive analysis of acrylamide in oils in different laboratories, with a limit of quantitation at 2 µg/kg, and the average recovery ranging from 92.5% to 107.8%, with relative standard deviations below 10%. When considering automation efficiency and matrix effects, gel permeation chromatography is the most efficient method, whereas the other method has an advantage when analyzing large samples. The developed methods were used in a pilot study to analyze frying oils with acrylamide content below 9.82 µg/kg, showing that the repeated frying process did not produce significant content of acrylamide in oils.
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Acrilamida , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Acrilamida/análise , Projetos Piloto , Cromatografia Líquida/métodos , Óleos , Cromatografia Líquida de Alta Pressão/métodosRESUMO
Thoracic aortic aneurysm and dissection (TAAD) is a lethal cardiovascular condition without effective pharmaceutical therapy. Identifying novel drugs that target the key pathogenetic components is an urgent need. Bioinformatics analysis of pathological studies indicated "extracellular matrix organization" as the most significant functional pathway related to TAAD, in which matrix metallopeptidase (MMP) 2 and MMP9 ranked above other proteases. MMP1-14 were designated as the prototype molecules for docking against PubChem Compound Database using Surflex-Dock, and nine natural compounds were identified. Using a generic MMP activity assay and an aminopropionitrile (BAPN)-induced TAAD mouse model, we identified crocin as an effective MMP inhibitor, suppressing the occurrence and rupture of TAAD. Biolayer interferometry and AI/bioinformatics analyses indicated that crocin may inhibit MMP2 activity by direct binding. Possible binding sites were investigated. Overall, the integration of artificial intelligence and functional experiments identified crocin as an MMP inhibitor with strong therapeutic potential.
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In this study, Coprinopsisjilinensis and Coprinopsispusilla were introduced, based on their morphological characteristics, the internal transcribed spacer (ITS) and large subunit ribosomal (LSU) region sequences of nrDNA. These new psathyrelloid species were found in Jilin Province, China. Coprinopsisjilinensis has brown pileus, utriform pleurocystidia, brown, smooth, dextrinoid basidiospores and tiny pore. It mainly grows on humus. Coprinopsispusilla has small basidiomata, greyish-white pileus, thick and distinct veil at edges, subcolourless and verrucose basidiospores. It is poreless and it grows on the decaying wood of broad-leaved trees. Both of them belong to the C.sect.Melanthinae. A supplementary description of C.sect.Melanthinae was given in combination with the newly-discovered taxa and an identification key to the fourteen psathyrelloid species of Coprinopsis is provided. Coprinopsissect.Canocipes and C.sect.Quartoconatae were evaluated and the phylogenetic position of the psathyrelloid species of Coprinopsis was discussed. Psathyrellasubagraria, as a confusing species, was also discussed in this study.
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Herein, a novel Fe3+-stabilized magnetic polydopamine composite (Fe3O4/PDA-Fe3+) was facilely constructed, systematically characterized, and subsequently applied for the first time as a versatile adsorbent for treatment of Methylene blue (MB) in complex wastewater. Results showed that as-prepared material had prominent adsorption ability toward MB in its single dye solution over a wide pH range (3-10) with qmax value of 608.8â¯mg/g at 318â¯K. More interestingly, MB could be selectively captured by resulting adsorbent from mixed dye solutions (MB-cationic dye and MB-anionic dye) and complex aqueous solution with high ionic strength up to 0.5â¯mol/L NaCl. It was eventually revealed that the enhanced and selective adsorption of MB by as-resultant adsorbent was due to the synergistic effects between multiple uptake mechanisms. What's more, its adsorption efficiency toward MB in simulated wastewater still maintained higher than 80 % of its original uptake performance after several runs of adsorption-desorption. Additionally, it exhibited more superior uptake performance toward MB than commercial powder activated carbon (PAC) in column adsorption system. Thus, the outstanding sorption ability, unique capture selectivity, as well as excellent stability and recyclability for model wastewater endow it a promising candidate adsorbent for selective adsorption and separation of MB from complex wastewater.
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A method was developed for the determination of nine antioxidants in vegetable oils by high performance liquid chromatography (HPLC). The samples were extracted with methanol, and the fat in the samples was degreased by freezing. Separation of the targeted compounds was performed on an XBridge C18 column in gradient elution mode using methanol-0.1% (v/v) formic acid aqueous solution as the mobile phase. The analytes were detected using a diode-array detector by the external standard method. The stability and storage conditions for the nine antioxidants were systematically investigated. Ascorbyl palmitate (AP) was introduced into the preparation and pre-treatment of the targets. The concentration of AP was optimized to improve the stability and recovery of the targets. The effects of different extraction solvents and purification methods on the extraction efficiencies were discussed. The results showed that the nine antioxidants could be separated well under the optimized conditions. Good linear relationships in the linear range were obtained, and the correlation coefficients (R2) were greater than 0.999. The average recoveries of the nine antioxidants ranged from 85.3% to 104.1%, with RSDs of the method ≤5.0%. The limits of quantitation (LOQs) for the nine synthetic antioxidants were in the range of 0.6-3.0 mg/kg. The method is simple, rapid, sensitive, and it shows good recovery and reproducibility.
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Antioxidantes , Análise de Alimentos/métodos , Óleos de Plantas , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão , Indicadores e Reagentes , Óleos de Plantas/análise , Reprodutibilidade dos TestesRESUMO
Alpinetin is a natural flavonoid showing a variety of pharmacological effects such as anti-inflammatory, anti-tumor and hypolipidemic activities. Here, we aim to determine the roles of UDP-glucuronosyltransferases (UGTs) and breast cancer resistance protein (BCRP) in disposition of alpinetin. Glucuronidation potential of alpinetin was evaluated using pooled human liver microsomes (pHLM), pooled human intestine microsomes (pHIM) and expressed UGT enzymes supplemented with the cofactor UDPGA. Activity correlation analyses with a bank of individual HLMs were performed to identify the main contributing UGT isozymes in hepatic glucuronidation of alpinetin. The effect of BCRP on alpinetin disposition was assessed using HeLa cells overexpressing UGT1A1 (HeLa1A1) cells. Alpinetin underwent extensive glucuronidation in pHLM and pHIM, generating one glucuronide metabolite. Of 12 test UGT enzymes, UGT1A3 was the most active one toward alpinetin with an intrinsic clearance (CLint = Vmax/Km) value of 66.5 µl/min/nmol, followed by UGT1A1 (CLint = 48.6 µl/min/nmol), UGT1A9 (CLint = 21.0 µl/min/nmol), UGT2B15 (CLint = 16.7 µl/min/nmol) and UGT1A10 (CLint = 1.60 µl/min/nmol). Glucuronidation of alpinetin was significantly correlated with glucuronidation of estradiol (an activity marker of UGT1A1), chenodeoxycholic acid (an activity marker of UGT1A3), propofol (an activity marker of UGT1A9) and 5-hydroxyrofecoxib (an activity marker of UGT2B15), confirming the important roles of UGT1A1, UGT1A3, UGT1A9 and UGT2B15 in alpinetin glucuronidation. Inhibition of BCRP by its specific inhibitor Ko143 significantly reduced excretion of alpinetin glucuronide, leading to a significant decrease in cellular glucuronidation of alpinetin. Our data suggest UGTs and BCRP as two important determinants of alpinetin pharmacokinetics.
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Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Flavanonas/farmacocinética , Glucuronosiltransferase/metabolismo , Proteínas de Neoplasias/metabolismo , Flavanonas/química , Flavanonas/metabolismo , Glucuronídeos/metabolismo , Células HeLa , Humanos , Intestinos , Cinética , Microssomos/metabolismo , Microssomos Hepáticos/metabolismoRESUMO
Ascribing to their significant differences in physicochemical properties, it is extremely challenging to treat complex wastewater containing more than one class of pollutants via one-step treatment. Here, we focused on disposal of complex wastewater bearing organic dye and heavy metal by using adsorptive method. Thus, by combining the advantages of polyethyleneimine (PEI), ß-cyclodextrin (ß-CD) as well as Fe3O4 magnetic nanoparticles, a versatile ß-CD and PEI bi-functionalized magnetic nanoadsorbent (Fe3O4-PEI/ß-CD) with spatially separated sorption sites was successfully constructed for simultaneous capture of methyl orange (MO) and Pb(II) in complex wastewater. In this setting, ß-CD cavities and positively charged N-containing groups of PEI were mainly responsible for removal of MO via host-guest inclusion and electrostatic attraction, respectively, and oxygen-bearing groups on the edge of ß-CD as well as the free amino moieties in PEI acted as the active sites for Pb(II) uptake. In their individual mono-pollutant system, the adsorption processes can be better described via applying pseudo-second-order kinetic and Langmuir isotherm models. Interestingly, presence of MO in Pb(II)-MO binary system significantly promoted the uptake of Pb(II). But the coexisting Pb(II) had almost no effects on MO uptake. Such results demonstrated that both MO and Pb(II) could be simultaneously and synergistically removed by Fe3O4-PEI/ß-CD through multiple mechanisms (such as electrostatic attraction, host-guest inclusion, chelating, etc.). Particularly, the excellent regeneration and stability make Fe3O4-PEI/ß-CD an ideal integrative adsorbent for purification of actual wastewater contaminated by MO and Pb(II). Thus, this study provides some insights into designing a well-performed and easily recyclable adsorbent for simultaneous and synergetic capture of both organic and inorganic contaminants in complex wastewater.
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Compostos Azo/isolamento & purificação , Chumbo/isolamento & purificação , Nanopartículas de Magnetita/química , Polietilenoimina/química , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , beta-Ciclodextrinas/química , Compostos Azo/análise , Compostos Azo/química , Chumbo/análise , Chumbo/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/químicaRESUMO
Most recently, the continuous deterioration of the aquatic environment triggered by both heavy metals and synthetic organic dyes has imparted serious threats to the ecosphere and drinking water safety. However, it is still extremely challenging to treat complex wastewater containing these two classes of pollutants via a one-step method owing to the significant differences in their physicochemical properties. In the current work, versatile magnetic MWCNTs decorated with PEI (denoted as MWCNTs@Fe3O4/PEI) was fabricated by a facile, rapid and reproducible strategy and applied to as a robust adsorbent for simultaneously removing methyl orange (MO) and Cr(vi) from aqueous solutions. The physicochemical properties of the as-designed nanohybrid were investigated using various analytical techniques, i.e. XRD, FT-IR, SEM, TEM, VSM, zeta potential, etc. It was found that the surface charge properties of the MWCNTs as well as its dispersion in aqueous solution were greatly changed after the introduction of PEI molecules. The resulting nanohybrid exhibited attractive adsorption capabilities toward anionic MO and Cr(vi). In the perspective of a mono-pollutant system, the time-dependent adsorption process matched well with a pseudo-second-order kinetics equation, the adsorption isotherm data at r.t. were well fitted by a Langmuir model with maximum monolayer uptake capacity of 1727.6 mg g-1 for MO and 98.8 mg g-1 for Cr(vi), and the removal process of both pollutants was thermodynamically spontaneous and exothermic. In the MO-Cr(vi) binary system, the uptake of Cr(vi) by the as-prepared adsorbent was evidently enhanced by the presence of MO, while the coexisting Cr(vi) exerted a small negative effect on the sorption of MO; which was attributed to the different adsorption mechanisms of both pollutants on the as-recommend adsorbent. The much better adsorbing performance of the resulting MWCNTs@Fe3O4/PEI for MO and Cr(vi) than that of the pristine MWCNTs or the MWCNTs/Fe3O4 composite was mainly ascribed to the high surface area of the MWCNTs, the high density of protonated N-rich groups of PEI as well as the excellent dispersion and solubility of the resulting nanocomposites. Moreover, the obtained nanohybrids can be easily recovered after being used by a permanent magnet and still retained high stability and excellent reusability after consecutive adsorption-desorption cycles, implying its great potential in practical applications. Therefore, the as-fabricated MWCNTs@Fe3O4/PEI composite could be recommended as a promising candidate adsorbent for the simultaneous capture of MO and Cr(vi) from complex wastewater via multiple uptake mechanisms (e.g. electrostatic attraction, π-π stacking and hydrogen bonding).
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Three new ecdysteroid glycosides (1-3) and one new ecdysteroid (4), were isolated from the roots of Serratula chinensis. Their structures were established on the basis of extensive spectroscopic analysis and chemical methods.
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Ecdisteroides/isolamento & purificação , Glicosídeos/isolamento & purificação , Raízes de Plantas/química , Ecdisteroides/química , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear BiomolecularRESUMO
1. Anhuienoside C (AC), a triterpenoid saponin derived from the traditional Chinese medicine (TCM) "Di Wu", has significant anti-inflammatory and anti-rheumatoid arthritis activities. Here we aimed to characterize the pharmacokinetics of AC and its deglycosylated metabolites in rats. 2. AC was administered to rats by intravenous injection or oral gavage. AC and its four deglycosylated metabolites (M1, M2, M3 and M4) in biological samples were quantified using a UPLC-QTOF/MS system. The pharmacokinetic data were analyzed by compartmental modeling. The metabolism of M1, M2, M3 and M4 was determined using rat liver microsomes (RLM) and rat intestine microsomes (RIM). The intestinal permeabilities of AC and its metabolites were evaluated using Parallel artificial membrane permeability assay (PAMPA) and MDR1-transfected Madin-Darby canine kidney cell (MDCK-MDR1) cell model. 3. AC pharmacokinetics was well described by the one-compartment model. The oral bioavailability of AC was exceedingly low (F = 0.03%). Consistently, AC was poorly distributed (< 0.08 µM) in major organs including the heart, liver, spleen, lung and kidney after oral uptake. Three of four deglycosylated metabolites (M2, M3, and M4) underwent further metabolism in RLM, generating five, two and five oxidized products, respectively. Both PAMPA and MDCK-MDR1 experiments showed that AC and its metabolites were poorly permeable. Furthermore, the net flux ratios derived from MDCK-MDR1 versus wild-type MDCK cells were, respectively 1.3, 1.5, 0.7, 1.2 and 0.6 for AC, M1, M2, M3 and M4, suggesting that these compounds were non-substrates of P-glycoprotein. 4. In conclusion, extensive pre-systemic metabolism and poor permeability were the main causes of low systemic exposures of oral AC and its four metabolites.
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Saponinas/farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Disponibilidade Biológica , Permeabilidade da Membrana Celular , Cães , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Células Madin Darby de Rim Canino , Microssomos Hepáticos/metabolismo , Ratos , Saponinas/metabolismoRESUMO
Two new triterpenoid glycosides, latifolosides R and S (1 and 2), were isolated from the leaves of Ilex latifolia by various column chromatographic methods. Their structures were elucidated based on NMR spectroscopic data and chemical evidence.
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Glicosídeos/isolamento & purificação , Ilex/química , Triterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Folhas de Planta/químicaRESUMO
A high-performance liquid chromatography method coupled with diode array detection (HPLC-DAD) was developed for simultaneous determination of two coumarins and eight flavonoids in Lophatherum gracile Brongn (Gramineae), namely 5-O-coumaroylquinic acid (i), 4-O-coumaroylquinic acid (ii), luteolin 6-C-ß-d-galactopyranosiduronic acid (1â2)-ß-d-glucopyranoside (iii), 7-O-ß-d-glucopyranosyl-6-C-α-l-arabinopy ranoside (iv), isoorientin (v), swertiajaponin (vi), luteolin 6-C-ß-d-galactopyranosiduronic acid (1â2)-α-l-arabinopyranoside (vii), Saponaretin (viii), swertisin (ix) and apigenin 6-C-ß-d-galactopyranosiduronic acid (1â2)-α-l-arabinopyranoside (x). The analysis was performed on Cosmosil MS-IIâ ¡ C18 column (250 × 4.6 mm, 5 µm) with gradient elution of 0.1% aqueous acetic acid and acetonitrile. The detection wavelength was 330 nm. The developed method was able to determine the bioactive compounds with excellent resolution, precision and recovery. The validated method was successfully applied for the analysis of the 10 bioactive compounds in n samples from different cultivated regions. The results indicated that the developed method can be used as a suitable quality control method for L. gracile.
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Cromatografia Líquida de Alta Pressão/métodos , Cumarínicos/análise , Flavonoides/análise , Extratos Vegetais/química , Poaceae/química , Cumarínicos/química , Flavonoides/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos TestesRESUMO
1.Anhuienoside C (A-C) is the main active component of the saponin exact of "Di Wu", an oral drug for rheumatism treatment in China. In this study, we aimed to elucidate the metabolic pathways of A-C by intestinal bacteria using the metabolomic approach. 2.Four deglycosylated metabolites (M1, M2, M3 and M4) were identified after A-C (50 µM) was incubated with rat fecal lysate. Chemical structures of these metabolites were determined by high-resolution masses and nuclear magnetic resonance (NMR). 3.A one-compartment pharmacokinetic model was used to describe the formation of bacterial metabolites at a dose of 10 µM A-C. The results revealed that formation of M1 and M2 was rapid, whereas formation of M3 was rather slow. Further, it was found that the metabolites were generated by successive cleavage of the glycosyl residues. 4.This is the first report that A-C is subjected to efficient bacterial metabolism in the gut with M1 and M2 as main metabolites. Our study should be helpful for a better understanding of in vivo disposition of oral A-C.
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Bactérias/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Intestinos/microbiologia , Espectrometria de Massas/métodos , Metabolômica/métodos , Saponinas/metabolismo , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Análise dos Mínimos Quadrados , Masculino , Metaboloma , Análise de Componente Principal , Ratos Sprague-Dawley , Saponinas/química , Saponinas/farmacocinética , Fatores de TempoRESUMO
A new ursane-type triterpenoid saponin, flaccidoside IV (1), and three new oleanane-type triterpenoid saponins, flaccidosides V-VII (2-4), along with 17 known saponins (5-21), were isolated from the rhizomes of Anemone flaccida. The structures of the new triterpenoid saponins were determined based on spectroscopic analyses and chemical methods. All the isolated saponins were tested for their inhibitory activities on lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophages, and several bisdesmosidic oleanane-type triterpenoid saponins (2, 7, and 10) showed significant inhibitory activities, which indicated they had potential anti-inflammatory activities under their noncytotoxic concentrations in vitro.