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1.
Chemosphere ; 336: 139241, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37330066

RESUMEN

Excessive phosphorus (P) and ammonia nitrogen (NH3-N) in water bodies can lead to eutrophication of the aquatic environment. Therefore, it is important to develop a technology that can efficiently remove P and NH3-N from water. Here, the adsorption performance of cerium-loaded intercalated bentonite (Ce-bentonite) was optimized based on single-factor experiments using central composite design-response surface methodology (CCD-RSM) and genetic algorithm-back propagation neural network (GA-BPNN) models. Based on the determination coefficient (R2), mean absolute error (MAE), mean square error (MSE), mean absolute percentage error (MAPE), and root mean square error (RMSE), the GA-BPNN model was found to be more accurate in predicting adsorption conditions than the CCD-RSM model. The validation results showed that the removal efficiency of P and NH3-N by Ce-bentonite under optimal adsorption conditions (adsorbent dosage = 1.0 g, adsorption time = 60 min, pH = 8, initial concentration = 30 mg/L) reached 95.70% and 65.93%. Furthermore, based on the application of these optimal conditions in simultaneous removal of P and NH3-N by Ce-bentonite, pseudo-second order and Freundlich models were able to better analyze adsorption kinetics and isotherms. It is concluded that the optimization of experimental conditions by GA-BPNN has some guidance and provides a new approach to explore adsorption performance after optimizing the conditions.


Asunto(s)
Cerio , Contaminantes Químicos del Agua , Fósforo , Bentonita , Amoníaco , Adsorción , Redes Neurales de la Computación , Cinética , Nitrógeno , Concentración de Iones de Hidrógeno
2.
Artículo en Inglés | MEDLINE | ID: mdl-35615689

RESUMEN

Aucubin, a natural compound isolated from herbal medicine, has been reported to possess multiple beneficial properties. In this study, we aimed to verify the anticancer effect of aucubin on breast cancer and investigate the effect of cancer on the intestinal flora and whether aucubin has a therapeutic effect on intestinal problems caused by cancer. We established the breast cancer model with mouse 4T1 cell line and BALB/c mice. Aucubin was given once a day by gavage for 14 days. The results showed that aucubin suppress the growth of tumor in vivo by inducing tumor cell apoptosis. The tumor suppression rate of aucubin could reach 51.31 ± 4.07%. Organ histopathology was evaluated by tissue staining, which demonstrated that aucubin could alleviate the organ inflammatory damage caused by breast cancer without visible side effects. Moreover, aucubin could increase the expression of colonic tight junction protein occluding and adjust the gut microbiome to normal level according to 16S rDNA high-throughput sequencing. Herein, our results provide evidence for developing aucubin as an alternative and safe therapeutic for breast cancer treatment.

3.
Anal Bioanal Chem ; 410(30): 7849-7858, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30284000

RESUMEN

A ternary deep eutectic solvent (TDES) was used as both template and functional monomer in the synthesis of TDES-based molecularly imprinted polymers (TDES-MIPs). A meticulous miniaturized solid-phase microextraction (mini-SPME) method followed by high-performance liquid chromatography (HPLC) were used for the optimal speciation of 3,4-dihydroxybenzoic acid (3,4-DHBA) in the needle of a syringe system with response surface methodology (RSM). Under the optimal conditions for the determination of 3,4-DHBA (amount of adsorbent (2 mg), sample volume (1 mL), cycles for adsorption and desorption (6)), the actual extraction amount was 8.46 µg g-1. The limits of detection (LODs, S/N = 3) for 3,4-DHBA in Ilex chinensis Sims were 0.26-0.31 µg mL-1, and the intra-day and inter-day precision (relative standard deviations, n = 4) after spiking with 5 µg mL-1, 100 µg mL-1, and 200 µg mL-1 were both less than 4.21%. The meticulous method (TDES-MIP-mini-SPME) combined with RSM offers a significant advance over existing methods, because of the meticulous operation and excellent selectivity of 3,4-DHBA from complex samples. Graphical abstract ᅟ.


Asunto(s)
Hidroxibenzoatos/análisis , Impresión Molecular , Hojas de la Planta/química , Polímeros/química , Medicamentos Herbarios Chinos/química , Estructura Molecular , Microextracción en Fase Sólida/métodos , Solventes/química
4.
J Sep Sci ; 41(17): 3424-3431, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29963767

RESUMEN

Ternary deep eutectic solvent magnetic molecularly imprinted polymers grafted on silica were developed for the selective recognition and separation of theophylline, theobromine, (+)-catechin hydrate, and caffeic acid from green tea through dispersive magnetic solid-phase microextraction. A new ternary deep eutectic solvent was adopted as a functional monomer. The materials obtained were characterized by FTIR spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, NMR spectroscopy, and powder X-ray diffraction. The practical recovery of the theophylline, theobromine, (+)-catechin hydrate, and caffeic acid isolated with ternary deep eutectic solvent magnetic molecularly imprinted polymers in green tea were 91.82, 92.13, 89.96, and 90.73%, respectively, and the actual amounts extracted were 5.82, 4.32, 18.36, and 3.69 mg/g, respectively. The new method involving the novel material coupled with dispersive magnetic solid-phase microextraction showed outstanding recognition, selectivity and excellent magnetism, providing a new perspective for the separation of bioactive compounds.


Asunto(s)
Catequina/análisis , Impresión Molecular , Microextracción en Fase Sólida , Té/química , Teobromina/análisis , Teofilina/análisis , Catequina/análogos & derivados , Campos Magnéticos , Polímeros/química , Dióxido de Silicio/química , Solventes/química
5.
Electrophoresis ; 39(8): 1111-1118, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29349784

RESUMEN

Novel magnetic molecularly imprinted polymers (MMIPs) with multiple-template based on silica were modified by four types of deep eutectic solvents (DESs) for the rapid simultaneous magnetic solid-phase extraction (MSPE) of tanshinone Ⅰ, tanshinone ⅡA, and cryptotanshinone from Salvia miltiorrhiza bunge; glycitein, genistein, and daidzein from Glycine max (Linn.) Merr; and epicatechin, epigallocatechin gallate, and epicatechin gallate from green tea, respectively. The synthesized materials were characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Single factor experiments were to explore the relationship between the extraction efficiency and four factors (the sample solution pH, amount of DESs for modification, amount of adsorbent, and extraction time). It was showed that the DES4-MMIPs have better extraction ability than the MMIPs without DESs and the other three DESs-modified MMIPs. The best extraction recoveries with DES4-MMIP were tanshinone Ⅰ (85.57%), tanshinone ⅡA (80.58%), cryptotanshinone (92.12%), glycitein (81.65%), genistein (87.72%), daidzein (92.24%), epicatechin (86.43%), epigallocatechin gallate (80.92%), and epicatechin gallate (93.64%), respectively. The novel multiple-template MMIPs materials modified by DES for the rapid simultaneous MSPE of active compounds were proved to reduce the experimental steps than single-template technique, and increase the extraction efficiency.


Asunto(s)
Impresión Molecular/métodos , Extractos Vegetales/aislamiento & purificación , Polímeros/química , Dióxido de Silicio/química , Extracción en Fase Sólida/métodos , Salvia miltiorrhiza/química , Extracción en Fase Sólida/normas , Análisis Espectral , Té/química
6.
Molecules ; 22(7)2017 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-28672835

RESUMEN

Different kinds of deep eutectic solvents (DES) based on choline chloride (ChCl) and ionic liquids (ILs) based on 1-methylimidazole were used to modify Fe3O4/molecularly imprinted polymers (Fe3O4/MIPs), and the resulting materials were applied for the rapid purification of alkaloid isomers (theobromine and theophylline) from green tea with magnetic solid-phase extraction (M-SPE). The M-SPE procedure was optimized using the response surface methodology (RSM) to analyze the maximum conditions. The materials were characterized by Fourier transform infrared spectroscopy (FI-IR) and field emission scanning electron microscopy (FE-SEM). Compared to the ILs-Fe3O4/MIPs, the DESs-Fe3O4/MIPs were developed for the stronger recognition and higher recoveries of the isomers (theophylline and theobromine) from green tea, particularly DES-7-Fe3O4/MIPs. With RSM, the optimal recovery condition for theobromine and theophylline in the M-SPE were observed with ratio of methanol (80%) as the washing solution, methanol/acetic acid (HAc) (8:2) as the eluent at pH 3, and an eluent volume of 4 mL. The practical recoveries of theobromine and theophylline in green tea were 92.27% and 87.51%, respectively, with a corresponding actual extraction amount of 4.87 mg•g-1 and 5.07 mg•g-1. Overall, the proposed approach with the high affinity of Fe3O4/MIPs might offer a novel method for the purification of complex isomer samples.


Asunto(s)
Compuestos Férricos/química , Té/química , Teobromina/aislamiento & purificación , Teofilina/aislamiento & purificación , Líquidos Iónicos/química , Fenómenos Magnéticos , Microscopía Electrónica de Rastreo , Impresión Molecular/métodos , Extracción en Fase Sólida/métodos , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier
7.
J Chromatogr Sci ; 55(8): 866-871, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28449063

RESUMEN

Deep eutectic solvents (DES) were formed from choline chloride (ChCl). DES-modified polymer monolithic (DES-M), template molecular polymer monolithic and non-DES-M without a molecular template were synthesized in identical process. These polymer materials were characterized by field emission scanning electron microscopy and Fourier transform infrared spectroscopy. The significant selective adsorption properties of the polymers were assessed by an absorption capacity experiment and solid-phase extraction (SPE). The optimized extraction procedure was as follows: ultrasonic time (30 min), optimal solvent (ethanol) and liquid to material ratio (20 mL g-1). Under this condition, the amount of quercetin extracted from Ginkgo biloba was 290.8 mg g-1. The purification of G. biloba was achieved by the SPE process. Based on the results, DESs-based monolithic cartridges can be used for simple and efficient extraction and as a pre-concentration technique for the purification of bioactive compounds or drugs in aqueous environments with high affinity and selectivity.


Asunto(s)
Ginkgo biloba/química , Extractos Vegetales/química , Quercetina/análisis , Quercetina/aislamiento & purificación , Extracción en Fase Sólida/métodos , Adsorción , Cromatografía Líquida de Alta Presión , Modelos Lineales , Polímeros , Quercetina/química , Sonicación
8.
J Sep Sci ; 39(23): 4465-4473, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27730734

RESUMEN

Different kinds of deep eutectic solvents based on choline chloride and ionic liquids based on 1-methylimidazole were used to modify hybrid molecularly imprinted polymers with the monomer γ-aminopropyltriethoxysilane-methacrylic and three templates (rutin, scoparone, and quercetin). The materials were adopted as solid-phase extraction packing agents, and were characterized by FTIR spectroscopy and field emission scanning electron microscopy. The hybrid molecularly imprinted polymers modified by deep eutectic solvents had high recoveries and a strong recognition of rutin, scoparone, and quercetin in Herba Artemisiae Scopariae than those modified by ionic liquids. In the procedure of solid-phase extraction, deep eutectic solvents-2-hybrid molecularly imprinted polymers were obtained with the best recoveries with rutin (92.27%), scoparone (87.51%), and quercetin (80.02%), and the actual extraction yields of rutin (5.6 mg/g), scoparone (2.3 mg/g), and quercetin (3.4 mg/g). Overall, the proposed approach with the high affinity of hybrid molecularly imprinted polymers might offer a novel method for the purification of complex samples.


Asunto(s)
Artemisia/química , Cumarinas/aislamiento & purificación , Impresión Molecular , Quercetina/aislamiento & purificación , Rutina/aislamiento & purificación , Líquidos Iónicos , Polímeros , Extracción en Fase Sólida , Solventes
9.
Talanta ; 152: 1-8, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-26992488

RESUMEN

A novel double-templates technique was adopted for solid-phase extraction packing agent, and the obtained hybrid molecularly imprinted polymers with double-templates (theophylline and chlorogenic acid) were characterized by fourier transform infrared and field emission scanning electron microscope. The molecular recognition ability and binding capability for theophylline and chlorogenic acid of polymers was evaluated by static absorption and dynamic adsorption curves. A rapid and accurate approach was established for simultaneous purification of theophylline and chlorogenic acid in green tea by coupling hybrid molecularly imprinted solid-phase extraction with high performance liquid chromatography. With optimization of SPE procedure, a reliable analytical method was developed for highly recognition towards theophylline and chlorogenic acid in green tea with satisfactory extraction recoveries (theophylline: 96.7% and chlorogenic acid: 95.8%). The limit of detection and limit of quantity of the method were 0.01 µg/mL and 0.03 µg/mL for theophylline, 0.05 µg/mL and 0.17 µg/mL for chlorogenic acid, respectively. The recoveries of proposed method at three spiked levels analysis were 98.7-100.8% and 98.3-100.2%, respectively, with the relative standard deviation less than 1.9%. Hybrid molecularly imprinted polymers with double-templates showed good performance for two kinds of targets, and the proposed approach with high affinity of hybrid molecularly imprinted polymers might offer a novel method for the purification of complex samples.


Asunto(s)
Ácido Clorogénico/aislamiento & purificación , Impresión Molecular , Polímeros/química , Polímeros/síntesis química , Extracción en Fase Sólida/métodos , Té/química , Teofilina/aislamiento & purificación , Adsorción , Ácido Clorogénico/química , Teofilina/química , Factores de Tiempo
10.
J Bacteriol ; 194(24): 6990, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23209238

RESUMEN

Nitratireductor indicus strain C115(T) was isolated from a crude-oil-degrading consortium enriched from deep seawater of the Indian Ocean. Here, we present the draft genome of strain C115(T), which contains 4,992,479 bp with a G+C content of 60.8% and contains 4,825 protein-coding genes and 45 tRNA genes.


Asunto(s)
Genoma Bacteriano , Phyllobacteriaceae/genética , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Biodegradación Ambiental , ADN Bacteriano/genética , Océano Índico , Consorcios Microbianos , Datos de Secuencia Molecular , Petróleo/metabolismo , Phyllobacteriaceae/clasificación , Filogenia , ARN Bacteriano/genética , Agua de Mar/microbiología , Análisis de Secuencia de ADN
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