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Structural adhesives that do not require heating are in high demand in the automotive and electronics industries. However, it remains a challenge to develop robust adhesives that rapidly achieve super adhesion near ambient temperature. Herein, a room-temperature curable, fast-bonding, and super strong epoxy-based structural adhesive was designed from the perspective of cross-scale structure, which lies in threefold pivotal aspects: (i) high branching topology of glycerol carbonate-capped polyurethane (PUGC) increases the kinetics of the ring-opening reaction, contributing to fast crosslinking and the formation of abundant urethane and hydroxyl moieties; (ii) asynchronous crosslinking of epoxy and PUGC synergistically induces phase separation of PUGC within the epoxy resin and the resulting PUGC domains surrounded by interpenetrated shell serves to efficiently toughen the matrix; (iii) abundant dynamic hydrogen bonds including urethane and hydroxyl moieties, along with the elastomeric PUGC domains, dissipate energy of shearing force. As a result, the adhesive strength rapidly grows to 16â MPa within 4â hours, leveling off to 21â MPa after 7â hours, substantially outperforming commercial room-temperature curable epoxy adhesives. The results of this study could advance the field of high-performance adhesives and provide valuable insights into designing materials for efficient curing at room temperature.
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Postoperative ileus (POI) is the cessation or reduction of gastrointestinal (GI) motility after surgery. Reactive enteric glial cells (EGCs) are critical for maintaining bowel function. However, the triggering mechanisms and downstream effects of reactive EGCs in POI were poorly understood. The goal of this current study was to investigate whether the inducible nitric oxide synthase (iNOS)-driven reactive EGCs participated in GI motility disorders and mechanisms underlying altered GI motility in POI. Intestinal manipulation (IM)-induced POI mice and iNOS-/- mice were used in the study. Longitudinal muscle and myenteric plexuses (LMMPs) from the distal small intestine were stained by immunofluorescence. Our results found that the GI motility disorders occurred in the IM-induced POI mice, and reactive EGCs were observed in LMMPs. Glial metabolic inhibitor gliotoxin fluorocitrate (FC) treatment or iNOS gene knockout attenuated GI motility dysfunction. In addition, we also found that FC treatment or iNOS gene knockout significantly inhibited the fluorescence intensity macrophage colony-stimulating factor (M-CSF), which reduced M2 phenotype macrophages activation in LMMPs of IM-induced POI mice. Our findings demonstrated that iNOS-driven reactive EGCs played a key role and were tightly linked to the MMs homeostasis in the POI mice. EGCs are emerging as a new frontier in neurogastroenterology and a potential therapeutic target.
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Ileus , Ratones , Animales , Óxido Nítrico Sintasa de Tipo II/metabolismo , Ileus/metabolismo , Motilidad Gastrointestinal/fisiología , Neuroglía/metabolismo , Intestino Delgado/metabolismoRESUMEN
Introduction: Owing to advancements in non-invasive magnetic resonance imaging, many studies have repeatedly showed that diabetes affects the central nervous system in the presence of peripheral neuropathy, suggesting a common or interacting pathological mechanism for both complications. Methods: We aimed to investigate the role of abnormal gut microbiota in rats with diabetic peripheral neuropathy (DPN) combined with cognitive dysfunction. Glucose-compliant rats with nerve conduction deficits were screened as a successful group of DPN rats. The DPN group was then divided into rats with combined cognitive impairment (CD) and rats with normal cognitive function (NCD) based on the results of the Novel object recognition test. Rat feces were then collected for 16S rRNA gene sequencing of the intestinal flora. Results and Discussion: The results revealed that abnormalities in Firmicutes, Ruminococcaceae, Bacteroidia, and Actinobacteria-like microorganisms may induce DPN complicated by cognitive dysfunction.
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Increasing evidence suggested that inhibiting the apoptosis of Schwann cells (SCs) and promoting nerve growth factor (NGF) expression in sciatic nerves play key roles in preventing the onset of diabetic peripheral neuropathy (DPN). Curcumin, a primary bioactive substance in turmeric with multiple characteristics, has been shown to have many therapeutic effects in a variety of diseases. However, curcumin is poorly studied in the DPN models. We aimed to explore the therapeutic benefits and underlying mechanism of curcumin in high fat/sugar diets joint streptozotocin (STZ)-induced DPN rat models. Sprague-Dawley (SD) rats were divided into five groups (6 rats per group), control group, DPN group, Curcumin groups (50, 100, and 150 mg/kg). Curcumin was administered intragastrically once per day for 4 continuous weeks. Body weight (BW) and fasting blood glucose (FBG) were monitored in all groups. The mechanical withdraw threshold (MWT) was measured. We also assessed neuropathic change by testing nerve conductance velocity (NCV) in sciatic nerves. TEM was applied to observe the sciatic nerves ultrastructure. The SCs apoptosis in sciatic nerves was stained using TUNEL kit. NGF contents in sciatic nerves and serum were detected using western blotting and ELISA analysis. The results showed curcumin had no obvious effect on the BW and FBG change. Curcumin (100 and 150â mg/kg) attenuated the MWT, NCV, and sciatic nerves ultrastructure in DPN rats. Curcumin (50, 100 and 150â mg/kg) reduced SCs apoptosis in sciatic nerves. In addition, curcumin at 150â mg/kg had the best efficacy in increasing protein expression of NGF in sciatic nerves and serum NGF level. Our work demonstrated that curcumin has neuroprotective effects for the treatment of DPN.
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Curcumina , Diabetes Mellitus , Neuropatías Diabéticas , Animales , Ratas , Curcumina/farmacología , Curcumina/uso terapéutico , Neuropatías Diabéticas/tratamiento farmacológico , Factor de Crecimiento Nervioso/metabolismo , Ratas Sprague-DawleyRESUMEN
Commercial diol chain extenders generally could only form two urethane bonds, while abundant hydrogen bonds were required to construct self-healing thermoplastic polyurethane elastomers (TPU). Herein, two diol chain extenders bis(2-hydroxyethyl) (1,3-pheny-lene-bis-(methylene)) dicarbamate (BDM) and bis(2-hydroxyethyl) (methylenebis(cyclohexane-4,1-diy-l)) dicarbamate (BDH), containing two carbamate groups were successfully synthesized through the ring-opening reaction of ethylene carbonate (EC) with 1,3-benzenedimetha-namine (MX-DA) and 4, 4'-diaminodicyclohexylmethane (HMDA). The two chain extenders were applied to successfully achieve both high strength and high self-healing ability. The BDM-1.7 and BDH-1.7 elastomers had high comprehensive self-healing efficiency (100%, 95%) after heated treatment at 60 °C, and exhibited exceptional comprehensive mechanical performances in tensile strength (20.6 ± 1.3 MPa, 37.1 ± 1.7 MPa), toughness (83.5 ± 2.0 MJ/m3, 118.8 ± 5.1 MJ/m3), puncture resistance (196.0 mJ, 626.0 mJ), and adhesion (4.6 MPa, 4.8 MPa). The peculiar mechanical and self-healing properties of TPUs originated from the coexisting short and long hard segments, strain-induced crystallization (SIC). The two elastomers with excellent properties could be applied to engineering-grade fields such as commercial sealants, adhesives, and so on.
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Reactive oxygen species (ROS) are an important component for maintaining normal physiological activities in organisms, and abnormal changes in their level are often accompanied by many diseases. As the two most representative components of ROS, HClO and H2O2 play vital roles in many physiological and pathological processes and are interdependent and mutually transformable. Although there is a lot of work that has specifically detected HClO or H2O2, there are few reports on the simultaneous differential detection of HClO and H2O2. Here, we report a ratio-based fluorescent probe capable of simultaneously distinguishing HClO and H2O2 based on making the best use of the untapped potential of coumarin derivatives. This probe was triumphantly put into use in the discriminative identification of HClO and H2O2 in aqueous media with high sensitivity and selectivity, and the probe was appropriate in a wide pH range. Furthermore, the imaging experiment for HClO and H2O2 in cells and zebrafish was eventually proven to be feasible. Importantly, this probe was qualified for monitoring the variation of HClO and H2O2 levels in organisms with alcoholic liver injury.
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Colorantes Fluorescentes , Ácido Hipocloroso , Animales , Colorantes Fluorescentes/análisis , Peróxido de Hidrógeno/análisis , Ácido Hipocloroso/análisis , Hígado/diagnóstico por imagen , Pez CebraRESUMEN
Liquid adhesive suffers from the emission of volatile organic compounds (VOCs) that have detrimental effects on human beings. Herein, an environmentally friendly glue containing a novel supramolecule dissolved in non-toxic ethanol is developed. Poly (ether amine) (PEA) and 3,4-dihydroxybenzaldehyde (dhba) is utilized to synthesize catechol-terminated PEA, and subsequent complexation by Fe3+ results in the supramolecular component (PEA-dhba-Fe3+). The Fourier transform infrared (FTIR) spectrum together with the UV-vis spectrum reveal the existence of quinone converted from catechol. Raman spectra prove the existence of a successful complex of catechol-terminated PEA with Fe3+. The tri-complex is found to be the predominant mode and can successfully form into clusters, serving as a physical cross-linking network. The PEA-dhba-Fe3+ exhibits strong adherence to metal substrates compared to polymeric substrates, with its shear strength reaching as high as 1.36 ± 0.14 MPa when the pH of the glue is adjusted to 8. The obvious improvement of adhesion originates from the formation of interfacial coordination bonds between quinone/catechol and metal atoms, as well as their cations, as revealed by X-ray photoelectron spectroscopy (XPS) and theoretical calculations. With consideration of its merits, including strong adhesion and the minor emission of VOCs compared to commercial epoxy and acrylic adhesives, this environmentally friendly supramolecular glue has a range of cutting-edge applications as an adhesive for metal substrates.
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The development of intrinsic self-healing elastomers with simultaneous high mechanical strength, toughness and room-temperature reparability remains a formidable challenge. Herein, we report a mechano-responsive strategy, known as strain induced crystallization, to address the above issue, whereby synthesized elastomers with unprecedented high mechanical performances are bestowed with room-temperature self-healing materials, achieving tensile strength, toughness and fracture energy values of 29.0 MPa, 121.8 MJ m-3 and 104.1 kJ m-2, respectively.
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Chemotherapeutic agents, which contain the Michael acceptor, are potent anticancer molecules by promoting intracellular reactive oxygen species (ROS) generation. In this study, we synthesized a panel of PL (piperlongumine) analogs with chlorine attaching at C2 and an electron-withdrawing/electron-donating group attaching to the aromatic ring. The results displayed that the strong electrophilicity group at the C2-C3 double bond of PL analogs plays an important role in the cytotoxicity whereas the electric effect of substituents, which attached to the aromatic ring, partly contributed to the anticancer activity. Moreover, the protein containing sulfydryl or seleno, such as TrxR, could be irreversibly inhibited by the C2-C3 double bond of PL analogs, and boost intracellular ROS generation. Then, the ROS accumulation could disrupt the redox balance, induce lipid peroxidation, lead to the loss of MMP (Mitochondrial Membrane Potential), and ultimately result in cell cycle arrest and A549 cell line death. In conclusion, PL analogs could induce in vitro cancer apoptosis through the inhibition of TrxR and ROS accumulation.
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Apoptosis , Dioxolanos/química , Especies Reactivas de Oxígeno , Células A549 , Antineoplásicos/farmacología , Ciclo Celular , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Cloro/química , Electrones , Humanos , Peroxidación de Lípido , Potencial de la Membrana Mitocondrial , Oxidación-Reducción , Sales de Tetrazolio/química , Tiazoles/química , Reductasa de Tiorredoxina-Disulfuro/metabolismoRESUMEN
BACKGROUND: Refractory pneumonia is a special type of pneumonia in children. This study aimed to analyze the effect of bronchoalveolar lavage (BAL) on the clinical efficacy, inflammatory factors, and immune function in the treatment of pediatric refractory pneumonia. METHODS: A total of 196 children with refractory pneumonia admitted to our hospital from January 2017 to January 2020 were enrolled and allocated to a study group (n=99) and a control group (n=97). The study group was treated with BAL treatment plus conventional treatment, and the control group was treated with conventional treatment. The clinical efficacy, time of fever regression, time of cough relief, and length of hospital stay were compared between groups. Changes in inflammatory factors, immune function, pulmonary ventilation function, and complications were analyzed. The levels of inflammatory factors in BAL fluid were compared. RESULTS: The times of fever remission, cough relief, and hospital stay of the study group was shorter than those of the control group, and the total clinical effective rate of the study group was higher. At any time after treatment, the levels of interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-α) in the study group were lower than the control group. After 3-day of treatment, IL-6, CRP and TNF-α in BAL fluid in the study group were significantly decreased compared with before treatment. Immunoglobulin A (IgA) and immunoglobulin G (IgG) levels in the study group were higher than those in the control group at any time after treatment, and immunoglobulin M (IgM) levels were lower than in the control group. The levels of oxygenation index (OI), lung dynamic compliance (Cdyn), and work of breathing (WOB) in the study group were higher than those in the control group at any time after treatment. CONCLUSIONS: BAL treatment can effectively relieve the inflammatory response, improve immune function and lung ventilation function in children with refractory pneumonia. The clinical effect is remarkable and worthy of promotion.
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A meta-analysis was performed to analyze the efficacy of 3% hypertonic saline (HS) in bronchiolitis. Pubmed and MEDLINE databases were searched for relevant articles. A total of 2 authors selected the articles according to the inclusion criteria and then data were carefully extracted. Weighted mean difference (WMD) with 95% confidence interval (95% CI) values were used to pool continuous data, including length of stay and clinical severity score (CSS). Relative risk (RR) with 95% CI was calculated to determine the association between 3% HS and re-admission. The pooled data revealed that infants treated with 3% HS exhibited shorter durations of hospitalization compared with those treated with normal saline (NS; WMD=-0.43; 95% CI=-0.70, -0.15). Subgroup analysis examining the combination of HS or NS with additional medication demonstrated that 3% HS with epinephrine significantly decreased the length of hospital stay, with a WMD=-0.62 (95% CI=-0.90, -0.33). The results indicated a lower CSS score in the 3% HS group compared with the NS group (SMD=-0.80; 95% CI=-1.06, -0.54). The pooled outcome indicated a beneficial effect of 3% HS on decreasing re-admission rates compared with NS (RR=0.93; 95% CI=0.70, 1.23). No potential publication bias was observed (Begg's, P=0.133; Egger's, P=0.576). In conclusion, 3% HS was demonstrated to be a more successful therapy compared with NS for infants with bronchiolitis.
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Conventional approaches to synthesize thermoplastic polyurethane (TPU) with excellent robustness are limited by a competing relationship between soft and hard segments for tuning mechanical properties in terms of chain flexibility and micro-phase separation. Herein, we present a facile and effective way of simultaneously improving the tensile strength, elongation, and toughness by constructing dynamic cross-linkages from metal-ligand interaction between Zn2+ and pyridine moiety in backbone of poly(urethane urea) (PUU) derived from 2,6-diaminopyridine and poly(propylene glycol). It was found that a Zn2+/pyridine ratio of 1:4 is the most effective for improving robustness. Specifically, tensile strength, elongation, and toughness could be remarkably increased to 16.0 MPa, 1286%, and 89.3 MJ/m3 with 226%, 29%, and 185% increments compared to uncomplexed PUU, respectively. Results from UV-vis, Fourier transform infrared spectroscopy (FTIR), cyclic tensile tests, and stress relaxation reveal that metal-ligand interaction significantly interferes with the hydrogen bonding of urea groups, thus leading to weakening of stiffness. Furthermore, half of vacant ligands enable dynamic complexation during stretching, which consequently ensures constant noncovalent cross-linkages for constraining mutual chain sliding, contributing to simultaneous improvement of tensile strength, elongation, and toughness. This work provides a promising approach for designing TPU with excellent robustness.
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Discharge rate is a key parameter affecting the cycle life of lithium-ion batteries (LIB). Normally, lithium-ion batteries deteriorate more severely at a higher discharge rate. In this paper, we report that the cycle performance of LiNi0.8Co0.15Al0.05O2/graphite high-energy 2.8 Ah 18650 cells is abnormally worse at a 1.5 C discharge rate than at a 2.0 C discharge rate. Combining macromethods with micromethods, the capacity/rate performance, electrochemical impedance spectroscopy (EIS), and scanning electron microscope (SEM) morphology of the electrodes are systematically investigated. We have found that the impedance of the negative electrodes after 2.0 C aged is smaller than that after 1.5 C aged, through EIS analysis, and the discharge rate performance of the negative electrodes after 2.0 C aged is better than that after 1.5 C aged through coin cell analysis. In addition, some special microcracks in the negative electrodes of aged cells are observed through SEM analysis, which can accelerate the side reaction between active and electrolyte and form the thicker SEI which will hinder the Li+ insertion and cause resistance increase. In short, the LiNi0.8Co0.15Al0.05O2/graphite-based lithium-ion batteries show better cycle life at a 2.0 C discharge rate than at a 1.5 C discharge rate which indicates that the negative electrodes contribute more than the positive electrodes.
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In this study, a preparative separation method was developed for isolation of eleven polyphenols from water-soluble fraction of Chinese propolis using macroporous absorptive resin (MAR) coupled with preparative high performance liquid chromatography (PHPLC). Water-soluble fraction of Chinese propolis was first "prefractioned" using MAR, which yielded four subfractions. The four subfractions were then isolated by PHPLC with an isocratic elution of methanol-water. Finally, eleven polyphenols were purified from Chinese propolis including caffeic acid, ferulic acid, isoferulic acid, 3,4-dimethoxy cinnamic acid, pinobanksin, caffeic acid benzyl ester, caffeic acid phenethyl ester, apigenin, pinocembrin, chrysin and galangin. The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. The method developed was simple, effective, rapid, scalable and economical, and it was a promising basis for large-scale preparation of multiple components from natural products.
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Cromatografía Líquida de Alta Presión/métodos , Polifenoles/análisis , Polifenoles/aislamiento & purificación , Própolis/química , Resonancia Magnética Nuclear Biomolecular , Polifenoles/químicaRESUMEN
PURPOSE: We aim to report a genetic testing and fertility guidance for the deaf through analyzing pedigree and molecular genetic characteristics of the couple who have non-syndromic sensorineural hearing loss (NSHL). METHODS: One of hospitalized congenial deaf couple and family members were included in this study. The wife was twin pregnant woman and her gestational age was 31(+5) pregnant weeks. The DNA was extracted from peripheral blood and umbilical vein blood, respectively. Mutation screening of common deafness genes was performed in pregnant women and other family members. Nine common mutations in four major deafness genes, GJB2 (35delG, 176del16, 235delC, 299delAT), GjB3 (C538T), SLC26A4 (IVS7-2A>G, A2168G) and Mitochondrial 12S rRNA (A1555G, C1494T), were detected simultaneously with a microarray based method. SLC26A4 whole genome sequencing was carried out for the results of the DNA microarray. According to the test results, the couple chose abortion termination of pregnancy twins, and after one year obtained singleton pregnancy by artificial insemination by donor (AID). In week 16 of pregnancy, amniocentesis had been done to collect fetal somatic cell and extract DNA, and then the above tests had been repeated. RESULTS: The couple had SLC26A4 combined heterozygous mutation. Both parents had SLC26A4 single heterozygous mutation. Twin fetuses had SLC26A4 combined heterozygous mutation. The probability of naturally being pregnant and bearing deaf children for the pregnant women was 100%. Fetus obtained by AID had SLC26A4 single heterozygous mutation. After the birth of the baby, her hearing has been normal. CONCLUSIONS: To reduce children with congenital deafness, screening high mutation sites by microarray, combined with pedigree analysis and gene sequencing is effective, and should be used as a routine inspection item for the deaf before marriage and pregnancy. On the basis of genetic testing for the couple with hearing loss, human assisted reproductive technology is a viable option to avoid the birth of infant with hereditary deafness.
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Seed storability in rice (Oryza sativa L.) is an important agronomic trait. Two segregating populations with N22 (indica) as a common parent, viz. a set of 122 backcross-inbred lines (BILs) derived from the backcross Nanjing35 (japonica)/N22//Nanjing35 and another population comprising 189 recombinant inbred lines (RILs) from the cross of USSR5 (japonica) and N22, were studied to detect quantitative trait loci (QTL) controlling seed storability. Germination percentage (GP) was used to evaluate seed storability after aging treated under three different conditions, viz. natural, artificial and combined aging treatments. A total of seven QTLs were identified on chromosomes 1, 2, 5, 6 and 9. Among them, a major QTL, qSSn-9, was common in the two populations. In contrast, four QTLs (qSSnj-2-1, qSSn-2-2, qSSn-5 and qSSn-6) were detected in BILs and the QTL qSSn-1 was identified in RILs, which was a new QTL for seed storability. The N22-derived alleles increased the seed storability at all the loci except qSSnj-2-1. We also investigated the effect of QTLs using five selected lines with high storability from BILs and verified qSSn-5 with a near-isogenic line (NIL). These results provide an opportunity for pyramiding or map-based cloning major QTLs for seed storability in rice.
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A reversed-phase high-performance liquid chromatography method for the simultaneous determination of jatrorrhizine, palmatine, and berberine in Huangbo, the dried bark of Chinese Corktree, was established by using 1-hexyl-3-methylimidazolium tertafluoroborate as a mobile phase additive. The chromatographic behavior of the three compounds on the C18 column was studied with four different types of 1-alkyl-3-methylimidazolium-based ionic liquids as the mobile phase additives. The effect of 1-hexyl-3-methylimidazolium tertafluoroborate was the best in the four investigated ionic liquids. The concentration of 1-hexyl-3-methylimidazolium tertafluoroborate and the pH of the mobile phase, which influenced the chromatographic behaviors of the three bioactive compounds, were investigated. The linearity, precision, accuracy, repeatability, limit of detection, and quantification of the proposed method were found to be satisfactory. To explain the role of ionic liquids as the mobile phase additives, the possible mechanism was also explored and discussed.
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Alcaloides de Berberina/análisis , Boratos/química , Imidazoles/química , Líquidos Iónicos/química , Rutaceae/química , Alcaloides de Berberina/química , Cromatografía de Fase InversaRESUMEN
OBJECTIVE: To study the chemical constituents of the peels of Trichosanthes kirilowii. METHODS: Many chromatographic techniques were used including repeated silica column chromatography, polyamide resin and semi-preparative high performance liquid chromatography. According to the physical and chemical properties and spectral analysis, the chemical structures of the compounds were determined. RESULTS: Thirteen compounds were isolated and identified as quercetin-3-O-[alpha-L-rhamnose(1 --> 2)-beta-D-glucopyranosyl]-5-O-beta-D-glucopyranoside (1), quercetin-3-O-rutinoside (2), apigenin-7-O-beta-D-glucopyranoside (3), diosmetin-7-O-beta-D-glucopyranoside (4), luteolin (5), apigenin (6), diosmetin (7), methyl palmitate (8), methyl stearate (9), palmitic acid (10), beta-sitosterol (11), alpha-spin-asterol (12) and stigmasterol (13). CONCLUSION: Compounds 1 - 3, 5 - 7 are isolated from this plant for the first time.
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Medicamentos Herbarios Chinos/química , Frutas/química , Trichosanthes/química , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/aislamiento & purificación , Flavonoides/química , Flavonoides/aislamiento & purificación , Glucósidos/química , Glucósidos/aislamiento & purificación , Estructura Molecular , Quercetina/análogos & derivados , Quercetina/química , Quercetina/aislamiento & purificaciónRESUMEN
A method for the rapid pretreatment and determination of bisphenol A in water samples based on vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography with fluorescence detection was proposed in this paper. A simple apparatus consisting of a test tube and a cut-glass dropper was designed and applied to collect the floating extraction drop in liquid-liquid microextraction when low-density organic solvent was used as the extraction solvent. Solidification and melting steps that were tedious but necessary once the low-density organic solvent used as extraction solvent could be avoided by using this apparatus. Bisphenol A was selected as model pollutant and vortex-assisted liquid-liquid microextraction was employed to investigate the usefulness of the apparatus. High-performance liquid chromatography with fluorescence detection was selected as the analytical tool for the detection of bisphenol A. The linear dynamic range was from 0.10 to 100 µg/L for bisphenol A, with good squared regression coefficient (r(2) = 0.9990). The relative standard deviation (n = 7) was 4.7% and the limit of detection was 0.02 µg/L. The proposed method had been applied to the determination of bisphenol A in natural water samples and was shown to be economical, fast, and convenient.
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In this study, a simple and efficient preparative procedure was developed for preparation of seven flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography (SPHPLC). First, the ethyl acetate fraction from the peel of T. kirilowii Maxim. obtained "prefractionation" using polyamide resin, which yielded two subfractions. And then the two subfractions were isolated by SPHPLC with an isocratic elution of methanol-water. Finally, seven known flavonoids were purified from 35 g of ethyl acetate extract including quercetin-3-O-[α-l-rhamnose (1â2)-ß-d-glucopyranosyl]-5-O-ß-d-glucopyranoside (19 mg), quercetin-3-O-rutinoside (24 mg), apigenin-7-O-ß-d-glucopyranoside (10mg), diosmetin-7-O-ß-d-glucopyranoside (45 mg), luteolin (21 mg), apigenin (15 mg), and diosmetin (56 mg). The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. In the present study, a simple, effective, and rapid procedure was established for preparative separation of multiple components from the peel of T. kirilowii Maxim. Furthermore, it was scalable and economical, so it was a promising basis for large-scale preparation of flavonoids from other plant extracts.