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1.
Chem Asian J ; 17(16): e202200396, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35792100

RESUMEN

Burns are the most common and devastating form of wounds and are usually accompanied by abnormal inflammation, inadequate extracellular matrix production, reduced angiogenesis, and lack of growth factor stimulation, which can significantly delay wound healing and lead to complications. Pearl powder, a traditional Chinese medicine, has been used to treat wound healing. In the present study, we found that supercritical CO2 extracted pearl peptides in the size range of ">10kd" have great potential to promote wound healing at the cellular level. Antioxidant hydrogels were designed using selenium-containing block-functionalized PEG/PPG polymers. Pearl peptide components were combined into polymeric materials to develop new promising wound dressings. It was shown that pearl peptide hydrogels increased skin fibroblast viability, enhanced cellular resistance to oxidative stress, enhanced tissue remodeling, promoted angiogenesis, and exhibited enhanced promotion in wound healing.


Asunto(s)
Antioxidantes , Quemaduras , Antioxidantes/farmacología , Quemaduras/tratamiento farmacológico , Carbonato de Calcio , Humanos , Hidrogeles/farmacología , Cicatrización de Heridas
2.
J Pharm Anal ; 12(6): 839-851, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36605579

RESUMEN

Glycyrrhizae Radix et Rhizoma, a traditional Chinese medicine also known as Gan Cao (GC), is frequently included in clinical prescriptions for the treatment of pneumonia. However, the pharmacological components of GC for pneumonia treatment are rarely explored. Gan An He Ji oral liquid (GAHJ) has a simple composition and contains GC liquid extracts and paregoric, and has been used clinically for many years. Therefore, GAHJ was selected as a compound preparation for the study of GC in the treatment of pneumonia. We conducted an in vivo study of patients with pneumonia undergoing GAHJ treatments for three days. Using the intelligent mass spectrometry data-processing technologies to analyze the metabolism of GC in vivo, we obtained 168 related components of GC in humans, consisting of 24 prototype components and 144 metabolites, with 135 compounds screened in plasma and 82 in urine. After analysis of the metabolic transformation relationship and relative exposure, six components (liquiritin, liquiritigenin, glycyrrhizin, glycyrrhetinic acid, daidzin, and formononetin) were selected as potential effective components. The experimental results based on two animal pneumonia models and the inflammatory cell model showed that the mixture of these six components was effective in the treatment of pneumonia and lung injury and could effectively downregulate the level of inducible nitric oxide synthase (iNOS). Interestingly, glycyrrhetinic acid exhibited the strongest inhibition on iNOS and the highest exposure in vivo. The following molecular dynamic simulations indicated a strong bond between glycyrrhetinic acid and iNOS. Thus, the current study provides a pharmaceutical basis for GC and reveals the possible corresponding mechanisms in pneumonia treatment.

3.
Adv Mater ; 34(25): e2107674, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34755922

RESUMEN

Aberrant glucose metabolism and immune evasion are recognized as two hallmarks of cancer, which contribute to poor treatment efficiency and tumor progression. Herein, a novel material system consisting of a glucose and TEMPO (2,2,6,6-tetramethylpiperidin-1-yl)oxyl) at the distal ends of PEO-b-PLLA block copolymer (glucose-PEO-b-PLLA-TEMPO), is designed to encapsulate clinical therapeutics CUDC101 and photosensitizer IR780. The specific core-shell rod structure formed by the designed copolymer renders TEMPO radicals excellent stability against reduction-induced magnetic resonance imaging (MRI) silence. Tumor-targeting moiety endowed by glucose provides the radical copolymer outstanding multimodal imaging capabilities, including MRI, photoacoustic imaging, and fluorescence imaging. Efficient delivery of CUDC101 and IR780 is achieved to synergize the antitumor immune activation through IR780-mediated photodynamic therapy (PDT) and CUDC101-triggered CD47 inhibition, showing M1 phenotype polarization of tumor-associated macrophages (TAMs). More intriguingly, this study demonstrates PDT-stimulated p53 can also re-educate TAMs, providing a combined strategy of using dual tumor microenvironment remodeling to achieve the synergistic effect in the transition from cold immunosuppressive to hot immunoresponsive tumor microenvironment.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Línea Celular Tumoral , Glucosa , Humanos , Imagen por Resonancia Magnética , Nanopartículas/química , Neoplasias/terapia , Fotoquimioterapia/métodos , Fototerapia , Polímeros/química , Microambiente Tumoral
4.
Nanoscale ; 13(35): 14713-14722, 2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34473183

RESUMEN

Efficient drug delivery, multifunctional combined therapy and real-time diagnosis are the main hallmarks in the exploitation of precision nanomedicine. Herein, an anthracene-functionalized micelle containing a magnetic resonance imaging (MRI) contrast agent, upconversion nanoparticles (UCNPs) and the photosensitizer IR780 is designed to achieve sustained drug release and enhanced photothermal and photodynamic therapy. The polymer-coated hybrid micelle was achieved by crosslinking anthracene-dimer with UV light (λ > 300 nm), which is converted from near-infrared (NIR) irradiation upon UCNPs. Besides, the water-insoluble photosensitizer IR780 is introduced into the system to achieve efficient drug delivery and photothermal and photodynamic synergistic therapy. As a consequence of NIR-induced anthracene-dimer formation, the cross-linked nanocomposite shows sustained drug release, and the enhanced retention effect of IR780 could increase the photothermal conversion efficiency. Importantly, the incorporation of 2,2,6,6-tetramethyl-piperidineoxyl (TEMPO) as a nitroxide MRI contrast agent presents the potential for real-time diagnosis via nanotheranostics, and the fluorescence imaging of IR780 is applied to monitor drug distribution and metabolism. This strategy of sustained drug delivery by anthracene-dimer formation through the better penetration depth of NIR-II fluorescence provides an executable platform to achieve enhanced phototherapy in biomedical applications.


Asunto(s)
Nanocompuestos , Nanopartículas , Fotoquimioterapia , Antracenos/farmacología , Línea Celular Tumoral , Micelas , Fototerapia
5.
Materials (Basel) ; 14(16)2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34442981

RESUMEN

Pearl powder is a biologically active substance that is widely used in traditional medicine, skin repair and maintenance. The traditional industrial extraction processes of pearl powder are mainly based on water, acid or enzyme extraction methods, all of which have their own drawbacks. In this study, we propose a new extraction process for these active ingredients, specifically, water-soluble components of pearl powder extracted by a CO2 supercritical extraction system (SFE), followed by the extraction efficiency evaluation. A wound-healing activity was evaluated in vitro and in vivo. This demonstrated that the supercritical extraction technique showed high efficiency as measured by the total protein percentage. The extracts exhibited cell proliferation and migration-promoting activity, in addition to improving collagen formation and healing efficiency in vivo. In brief, this study proposes a novel extraction process for pearl powder, and the extracts were also explored for wound-healing bioactivity, demonstrating the potential in wound healing.

6.
Materials (Basel) ; 14(11)2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34074019

RESUMEN

Pearl powder is a well-known traditional Chinese medicine for a variety of indications from beauty care to healthcare. While used for over a thousand years, there has yet to be an in-depth understanding and review in this area. The use of pearl powder is particularly growing in the biomedical area with various benefits reported due to the active ingredients within the pearl matrix itself. In this review, we focus on the emerging biomedical applications of pearl powder, touching on applications of pearl powder in wound healing, bone repairing, treatment of skin conditions, and other health indications.

7.
Acta Pharm Sin B ; 11(1): 222-236, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33072499

RESUMEN

Lianhuaqingwen (LHQW) capsule, a herb medicine product, has been clinically proved to be effective in coronavirus disease 2019 (COVID-19) pneumonia treatment. However, human exposure to LHQW components and their pharmacological effects remain largely unknown. Hence, this study aimed to determine human exposure to LHQW components and their anti-COVID-19 pharmacological activities. Analysis of LHQW component profiles in human plasma and urine after repeated therapeutic dosing was conducted using a combination of HRMS and an untargeted data-mining approach, leading to detection of 132 LHQW prototype and metabolite components, which were absorbed via the gastrointestinal tract and formed via biotransformation in human, respectively. Together with data from screening by comprehensive 2D angiotensin-converting enzyme 2 (ACE2) biochromatography, 8 components in LHQW that were exposed to human and had potential ACE2 targeting ability were identified for further pharmacodynamic evaluation. Results show that rhein, forsythoside A, forsythoside I, neochlorogenic acid and its isomers exhibited high inhibitory effect on ACE2. For the first time, this study provides chemical and biochemical evidence for exploring molecular mechanisms of therapeutic effects of LHQW capsule for the treatment of COVID-19 patients based on the components exposed to human. It also demonstrates the utility of the human exposure-based approach to identify pharmaceutically active components in Chinese herb medicines.

8.
Medicine (Baltimore) ; 99(51): e23679, 2020 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-33371107

RESUMEN

INTRODUCTION: Myasthenia gravis (MG) is an autoimmune disease in which antibodies directly target components of the neuromuscular junction, causing neuromuscular conduction damage that leads to muscle weakness. The current pharmaceutical treatment for MG is still not ideal to address the problems of disease progression, high recurrence rate, and drug side effects. Clinical observations suggest that traditional Chinese medicine (TCM) can strengthen immunity and improve symptoms of MG patients, delay the progression of the disease, reduce or even prevent the need for immunosuppressive therapy when used in combination with acetylcholinesterase inhibitors or low-dose prednisone, as well as improve the quality of life of patients. The Qiangji Jianli Capsule (QJC) is a combination of medicinal herbs which is used in traditional Chinese medicine. Since MG is a rare disorder, randomized controlled trials comparing large cohorts are difficult to conduct. Therefore, we proposed to aggregate data from a small series of N-of-1 trials to assess the effect of the Chinese medical prescription QJC, which strengthens the spleen and nourishes Qi, as an add-on treatment for MG with spleen and stomach Qi deficiency syndrome. METHODS AND ANALYSIS: Single-center, randomized, double-blind, multiple crossover N-of-1 studies will compare QJC versus placebo in 5 adult MG patients with spleen and stomach Qi deficiency syndrome. Patients will undergo 3 cycles of two 4-week intervention periods. According to the treatment schedule, patients will continue to be treated with pyridine bromide tablets, prednisone acetate, tablets and/or tacrolimus capsules throughout the entire trial. Each period consisting of 4-week oral add-on treatment with QJC will be compared with 4-week add-on treatment with a placebo. The primary endpoints are quantitative myasthenia gravis (QMG) test; measurement of the amount of Treg cells and cytokines such as interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-17A (IL-17A), and transforming growth factor-ß (TGF-ß); and corticosteroid or immunosuppressive agent dosage. Secondary outcome measures: Clinical: Evaluation of the effect of TCM syndromes; MG-activities of daily living (MG-ADL) scales; adverse events. ETHICS AND DISSEMINATION: This study was approved by The First Affiliated Hospital of Guangzhou University of Chinese Medicine (GZUCM), No. ZYYECK[2019]038. The results will be published in a peer-reviewed publication. Regulatory stakeholders will comment on the suitability of the trial for market authorization and reimbursement purposes. Trial registration: Chinese Clinical Trial Register, ID: ChiCTR2000033516. Registered on 3 June 2020, http://www.chictr.org.cn/showprojen.aspx?proj=54618.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Miastenia Gravis/tratamiento farmacológico , Estudios Cruzados , Método Doble Ciego , Humanos , Medicina Tradicional China , Ensayos Clínicos Controlados Aleatorios como Asunto
9.
Adv Mater ; 32(12): e1907030, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32072703

RESUMEN

Bacterial infections remain a leading threat to global health because of the misuse of antibiotics and the rise in drug-resistant pathogens. Although several strategies such as photothermal therapy and magneto-thermal therapy can suppress bacterial infections, excessive heat often damages host cells and lengthens the healing time. Here, a localized thermal managing strategy, thermal-disrupting interface induced mitigation (TRIM), is reported, to minimize intercellular cohesion loss for accurate antibacterial therapy. The TRIM dressing film is composed of alternative microscale arrangement of heat-responsive hydrogel regions and mechanical support regions, which enables the surface microtopography to have a significant effect on disrupting bacterial colonization upon infrared irradiation. The regulation of the interfacial contact to the attached skin confines the produced heat and minimizes the risk of skin damage during thermoablation. Quantitative mechanobiology studies demonstrate the TRIM dressing film with a critical dimension for surface features plays a critical role in maintaining intercellular cohesion of the epidermis during photothermal therapy. Finally, endowing wound dressing with the TRIM effect via in vivo studies in S. aureus infected mice demonstrates a promising strategy for mitigating the side effects of photothermal therapy against a wide spectrum of bacterial infections, promoting future biointerface design for antibacterial therapy.


Asunto(s)
Antibacterianos/química , Fototerapia , Infecciones Estafilocócicas/terapia , Resinas Acrílicas/química , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Vendajes , Oro/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/efectos de la radiación , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/efectos de la radiación , Hidrogeles/química , Rayos Infrarrojos/uso terapéutico , Nanopartículas del Metal/química , Ratones , Infecciones Estafilocócicas/patología , Infecciones Estafilocócicas/veterinaria
10.
Biomater Sci ; 8(5): 1364-1379, 2020 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-31916556

RESUMEN

Current treatments for oral mucosa-related ulcers use drugs to relieve pain and promote healing, but rarely consider drug resistance to bacterial infection in the microenvironment of the oral cavity or the prevention of bleeding from gingival mucosa ulcers. We herein report an injectable, thermogelling chitosan-based system to address these concerns. An aqueous solution of chitosan-based conjugates (chitosan-g-poly(N-isopropylacrylamide) [CS-g-PNIPAAM] including 1a [CS-g-PNIPAAM with less PNIPAAM] and 1b [CS-g-PNIPAAM with more PNIPAAM], and chitosan-g-poly(N-isopropylacrylamide)-g-polyacrylamide [CS-g-PNIPAAM-g-PAM] 3) could reversibly form semi-solid gels at physiological temperatures for easy application to oral cavity ulcer sites by injection. The chitosan-based conjugate thermogels prepared could inhibit both Gram-positive and Gram-negative bacteria and the two with higher chitosan and poly(N-isopropylacrylamide) contents (1a and 1b) promoted proliferation of gingival fibroblasts in vitro. These two thermogels also exhibited improved blood clotting in an in vivo rat study. Thermogels 1a and 1b effectively promoted ulcer healing and shortened ulcer healing times in an oral gingival mucosa ulcer model using Sprague Dawley (SD) rats. These thermogels showed no obvious toxicity to the main organs of SD rats undergoing gingival ulcer treatment. These results suggest that this antibacterial biomaterial could be a promising injectable therapeutic agent for the treatment for oral mucosa ulcers.


Asunto(s)
Antibacterianos/farmacología , Antiulcerosos/farmacología , Quitosano/farmacología , Mucosa Bucal/efectos de los fármacos , Polímeros/farmacología , Úlcera/tratamiento farmacológico , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Antiulcerosos/síntesis química , Antiulcerosos/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Escherichia coli/efectos de los fármacos , Geles/síntesis química , Geles/química , Geles/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Mucosa Bucal/patología , Polímeros/química , Ratas , Ratas Sprague-Dawley , Staphylococcus aureus/efectos de los fármacos , Temperatura , Úlcera/patología
11.
Adv Healthc Mater ; 8(15): e1900406, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31183979

RESUMEN

Rational design of controllable drug release systems is important for tumor treatments due to the nonspecific toxicity of many chemotherapeutics. Herein, laser or light responsive pharmaceutical delivery nanoparticles are designed, by taking the advantages of redox responsive selenium (Se) substituted polymer as shell and photosensitive porphyrin zirconium metal-organic frameworks (MOF) as core. In detail, redox cleavable di-(1-hydroxylundecyl) selenide (DH-Se), biocompatible poly(ethylene glycol) (PEG), and poly(propylene glycol) (PPG) are randomly polymerized to form poly(DH-Se/PEG/PPG urethane), which is used to coat the reactive oxygen species' (ROS) producible porous porphyrin zirconium metal organization formulation (PCN-224 MOF) to form the final poly(DH-Se/PEG/PPG urethane)@MOF shell-core nanoparticle with spherical shape by emulsion approach. Interestingly, poly(DH-Se/PEG/PPG urethane)@MOF nanoparticles with loading of chemotherapeutic doxorubicin (DOX) experience a fast and controllable release, which can realize the combination of chemotherapy and photodynamic therapy upon irradiation with laser light, due to the light-triggered ROS production by MOF which further causes the cleavage of poly(DH-Se/PEG/PPG urethane) polymer chain and the release of encapsulated DOX. To the best of the authors' knowledge, this is the first design of utilizing MOF and selenium substituted polymer as controllable drug release carriers, which might be beneficial for precise chemotherapy and photodynamic therapy combination.


Asunto(s)
Portadores de Fármacos/química , Luz , Estructuras Metalorgánicas/química , Nanocompuestos/química , Polímeros/química , Selenio/química , Animales , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/metabolismo , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Liberación de Fármacos , Células Hep G2 , Humanos , Ratones , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/terapia , Oxidación-Reducción , Polietilenglicoles/química , Especies Reactivas de Oxígeno/metabolismo
12.
Nanoscale ; 9(41): 15753-15759, 2017 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-28994849

RESUMEN

Star fruit (Averrhoa carambola) juice rich in vitamin C and polyphenolic antioxidants was used to synthesize branched gold nanoflowers. These biocompatible and stable gold nanoflowers show strong near-infrared absorption. They are successfully demonstrated to be highly efficient for both in vitro and in vivo photothermal therapy by using an 808 nm laser.


Asunto(s)
Oro , Nanopartículas del Metal , Neoplasias Experimentales/terapia , Fototerapia , Animales , Jugos de Frutas y Vegetales , Tecnología Química Verde , Humanos , Rayos Láser , Células MCF-7 , Ratones Endogámicos BALB C , Ratones Desnudos , Oxalidaceae/química
13.
J Chromatogr A ; 1519: 145-151, 2017 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-28886939

RESUMEN

A novel on-line comprehensive two-dimensional liquid chromatography (2D-LC) method by coupling mixed-mode gel liquid chromatography (MMG-LC) with reversed phase liquid chromatography (RPLC) was developed. A mixture of 17 reference compounds was used to study the separation mechanism. A crude water extract of Flos Carthami was applied to evaluate the performance of the novel 2D-LC system. In the first dimension, the extract was eluted with a gradient of water/methanol over a cross-linked dextran gel Sephadex LH-20 column. Meanwhile, the advantages of size exclusion, reversed phase partition and adsorption separation mechanism were exploited before further on-line reversed phase purification on the second dimension. This novel on-line mixed-mode Sephadex LH-20×RPLC method provided higher peak resolution, sample processing ability (2.5mg) and better orthogonality (72.9%) versus RPLC×RPLC and hydrophilic interaction liquid chromatography (HILIC)×RPLC. To the best of our knowledge, this is the first report of a mixed-mode Sephadex LH-20×RPLC separation method with successful applications in on-line mode, which might be beneficial for harvesting targets from complicated medicinal plants.


Asunto(s)
Técnicas de Química Analítica/métodos , Cromatografía Liquida , Cromatografía de Fase Inversa , Medicamentos Herbarios Chinos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Agua/química , Dextranos/química , Medicamentos Herbarios Chinos/química , Interacciones Hidrofóbicas e Hidrofílicas
14.
Bioorg Med Chem Lett ; 26(15): 3813-7, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27289323

RESUMEN

Polycomb repressive complex 2 (PRC2) acts as a primary writer for di- and tri-methylation of histone H3 at lysine 27. This protein plays an essential role in silencing gene expression. Enhancer of zeste 2 (EZH2), the catalytic subunit of PRC2, is considered as a promising therapeutic target for cancer. GSK126, a specific inhibitor of EZH2, is undergoing phase I trials for hypermethylation-related cancers. In addition, many derivatives of GSK126 are also commonly used in laboratory investigations. However, studies on the mechanism and drug development of EZH2 are limited by the absence of structural diversity of these inhibitors because they share similar SAM-like scaffolds. In this study, we generated a pharmacophore model based on reported EZH2 inhibitors and performed in silico screenings. Experimental validations led to the identification of two novel EZH2 inhibitors, DCE_42 and DCE_254, with IC50 values of 23 and 11µM, respectively. They also displayed significant anti-proliferation activity against lymphoma cell lines. Thus, we discovered potent EZH2 inhibitors with novel scaffold using combined in silico screening and experimental study. Results from this study can also guide further development of novel specific EZH2 inhibitors.


Asunto(s)
Antineoplásicos/farmacología , Proteína Potenciadora del Homólogo Zeste 2/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Humanos , Estructura Molecular , Relación Estructura-Actividad
15.
J Chromatogr A ; 1406: 215-23, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26129983

RESUMEN

This study describes a novel on-line two-dimensional countercurrent chromatography×high performance liquid chromatography (2D CCC×HPLC) system for one-step preparative isolation of coumarins from the fruits of Cnidium monnieri. An optimal biphasic solvent system composed of n-heptane/acetone/water (31:50:19, v/v) with suitable Kd values and a higher retention of the stationary phase was chosen to separate target compounds. In order to address the solvent incompatibility problem between CCC and RP-HPLC, a novel fragmentary dilution and turbulent mixing (FD-TM) interface was successfully developed. In detail, the eluent from the first dimensional CCC column was divided into fractions to form 'sample-dilution' stripes in the two switching sample loops, by the dilution water from the makeup pump. Following this, a long, thin tube was applied to mix the CCC eluent with water by in-tube turbulence, to reduce the solvent effect. Each CCC fraction was alternately trapped on the two holding columns for further preparative HPLC separation. This nationally designed FD-TM strategy effectively reduced post-column pressure and allowed a higher water dilution ratio at the post end of CCC, leading to improved sample recovery and a robust 2D CCC×HPLC isolation system. As a result, in a single 2D separation run (6.5h), eight target compounds (1-8) were isolated from 0.5g crude extract of C. monnieri, in overall yields of 1.3, 2.0, 0.5, 0.5, 0.8, 1.5, 8.2, and 15.0%, with HPLC purity of 90.1, 91.1, 94.7, 99.1, 99.2, 98.2, 97.9, and 91.9%, respectively. We anticipate that this improved 2D CCC×HPLC system, based on the novel FD-TM interface, has broad application for simultaneous isolation and purification of multiple components from other complex plant-derived natural products.


Asunto(s)
Técnicas de Química Analítica/métodos , Cromatografía Líquida de Alta Presión , Cnidium/química , Cumarinas/aislamiento & purificación , Distribución en Contracorriente , Técnicas de Química Analítica/instrumentación , Cumarinas/química , Técnicas de Dilución del Indicador , Extractos Vegetales/química , Solventes/química
16.
Artículo en Inglés | MEDLINE | ID: mdl-26114653

RESUMEN

Herein, we report an on-line two-dimensional system constructed by counter-current chromatography (CCC) coupling with preparative high-performance liquid chromatography (prep-HPLC) for the separation and purification of polar natural products. The CCC was used as the first dimensional isolation column, where an environmental friendly polar two-phase solvent system of isopropanol and 16% sodium chloride aqueous solution (1:1.2, v/v) was introduced for low toxicity and favorable resolution. In addition, by applying the stop-and-go flow technique, effluents pre-fractionated by CCC was further purified by a preparative column packed with octadecyl silane (ODS) as the second dimension. The interface between the two dimensions was comprised of a 6-port switching valve and an electronically controlled 2-position 10-port switching valve connected with two equivalent holding columns. To be highlighted here, this rationally designed interface for the purpose of smooth desalination, absorption and desorption, successfully solved the solvent compatibility problem between the two dimensional separation systems. The present integrated system was successfully applied in a one-step preparative separation and identification of 10 pure compounds from the water extracts of Tieguanyin tea (Chinese oolong tea). In short, all the results demonstrated that the on-line 2D CCC×LC method is an efficient and green approach for harvesting polar targets in a single step, which showed great promise in drug discovery.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Distribución en Contracorriente/métodos , Extractos Vegetales/química , Polifenoles/aislamiento & purificación , Té/química , Polifenoles/análisis , Polifenoles/química , Reproducibilidad de los Resultados
17.
J Chromatogr A ; 1374: 156-163, 2014 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-25480680

RESUMEN

Pure compounds isolated from complex natural plants are important for drug discovery. This study describes a novel two-dimensional hyphenation of counter-current chromatography and high-performance liquid chromatography (2D CCC×HPLC) with heart-cutting and stop-and-go techniques for preparative isolation of multiple targets components from Peucedanum praeruptorum Dunn (Umbelliferae) crude extracts in a single step. The CCC and HPLC were hyphenated via a 4-port valve equipped at the post-end of the CCC column, to heart cut the impure fractions to the 2nd dimensional HPLC for further separation. Furthermore, the stop-and-go flow scheme was applied in the 1st dimensional CCC to fit with the time constraints of the 2nd dimensional preparative HPLC. Last but not least, an optimal biphasic solvent system composed of n-heptane/acetone/water (31:50:19, v/v/v) with suitable Kd values and a higher retention of the stationary phase was chosen to separate target compounds, resulting in the improvement of the CCC column efficiency. By taking the advantages of this rationally designed system, sixteen coumarins were isolated from 1.0g of P. praeruptorum crude extract, with HPLC purity from 90.1% to 99.5%, in a single 2D separation run. More interestingly, two minor linear coumarins and one angular coumarin were isolated from P. praeruptorum Dunn for the first time. As far as we known, this is the first report on the combination of heart-cutting technique and stop-and-go protocol in 2D CCC×HPLC system, by which good separations on comprehensive matrix were achieved. We expect that this approach may have broad applications for simultaneous isolation and purification of multiple components from other complex plant-derived natural products.


Asunto(s)
Apiaceae/química , Cromatografía Líquida de Alta Presión/métodos , Cumarinas/aislamiento & purificación , Distribución en Contracorriente/métodos , Cromatografía Líquida de Alta Presión/instrumentación , Extractos Vegetales/química , Solventes/química
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