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1.
J Sep Sci ; 46(8): e2200984, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36795010

RESUMEN

Phorbol is a tetracyclic diterpenoid found in Euphorbia tirucalli, Croton tiglium, and Rehmannia glutinosa, and is nuclear of various phorbol esters. The rapid obtaining of phorbol with high purity highly contributes to its application, such as synthesizing phorbol esters with designable side chains and particular therapeutic efficacy. This study introduced a biphasic alcoholysis method for obtaining phorbol from croton oil by using polarity imparity organic solvents in both phases and established a high-speed countercurrent chromatography method for simultaneous separation and purification of phorbol. The optimized operation conditions of biphasic alcoholysis were a reaction time of 91 min, a temperature of 14°C, and a croton oil-methanol ratio of 1:30 (g:ml). The phorbol during the biphasic alcoholysis was 3.2-fold higher in content than that obtained in conventional monophasic alcoholysis. The optimized high-speed countercurrent chromatography method was using the ethyl acetate/n-butyl alcohol/water at 4.7:0.3:5 (v:v:v) with Na2 SO4 at 0.36 g/10 ml as the solvent system, using the mobile phase flow rate of 2 ml/min, the revolution of 800 r/min, under which the retention of the stationary phase was achieved at 72.83%. The crystallized phorbol following high-speed countercurrent chromatography was obtained as high purity of 94%.


Asunto(s)
Distribución en Contracorriente , Forboles , Distribución en Contracorriente/métodos , Aceite de Crotón , Solventes/química , Extractos Vegetales/química , Ésteres del Forbol , Cromatografía Líquida de Alta Presión
2.
Molecules ; 27(21)2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36364136

RESUMEN

In order to improve the mechanical strength and imprinting efficiency, a novel bovine serum albumin (BSA) molecularly imprinted poly(ionic liquid)/calcium alginate composite cryogel membrane (MICM) was prepared. The results of the tensile test indicated that the MICM had excellent mechanical strength which could reach up to 90.00 KPa, 30.30 times higher than the poly (ionic liquid) membrane without calcium alginate; the elongation of it could reach up to 93.70%, 8.28 times higher than the poly (ionic liquid) membrane without calcium alginate. The MICM had a very high welling ratio of 1026.56% and macropore porosity of 62.29%, which can provide effective mass transport of proteins. More remarkably, it had a very high adsorption capacity of 485.87 mg g-1 at 20 °C and 0.66 mg mL-1 of the initial concentration of BSA. Moreover, MICM also had good selective and competitive recognition toward BSA, exhibiting potential utility in protein separation. This work can provide a potential method to prepare the protein-imprinted cryogel membrane with both high mechanical strength and imprinting efficiency.


Asunto(s)
Líquidos Iónicos , Impresión Molecular , Criogeles , Albúmina Sérica Bovina , Alginatos , Impresión Molecular/métodos , Adsorción
3.
J Chem Phys ; 150(20): 204507, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31153173

RESUMEN

Glassy materials are nonequilibrium and their energy states have crucial influences on properties. Recent studies have shown that oscillating deformations (vibrations) can cause either accelerated aging (lowering energy) or rejuvenation (elevating energy); however, the underlying atomic mechanisms remain elusive. Using metallic glasses (MGs) as model systems, we show that the vibration-induced accelerated aging is correlated with the strain field of the stringlike atomic motions stemming from the Johari-Goldstein (ß) relaxation, whereas the rejuvenation is associated with nonlinear response and the formation of nanoscale shear bands attributing to the activation of α relaxation. Both processes are affected by thermal fluctuations, which result in an optimal temperature for accelerated aging. These results suggest intrinsic correlations among relaxation dynamics, mechanical properties, and the vibration induced structural rearrangements in MGs.

4.
ACS Appl Mater Interfaces ; 13(24): 29130-29136, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34126739

RESUMEN

The natural-product-based low-molecular-weight supramolecular hydrogels (LMWSHs) induced by heating are rarely reported. In this work, a simple salt of oleanolic acid (OA) and choline ([choline][OA]) was used as the natural product hydrogelator (NPHG) to form LMWSHs. Unlike common sol-gel transitions, the OA-based LMWSH displayed a unique property with which the system could undergo a phase transition from the sol state to the gel state upon heating. Moreover, the phase separation was observed in sol and gel states when the temperature was elevated with nonreversible transparent-turbid transitions. LMWSHs showed good stability and injectability and the potential to be a drug delivery vehicle for sustained release of drugs. In this regard, this work provided a facile approach to designing an OA-based NPHG for preparing heat-induced LMWSHs.

5.
Chem Commun (Camb) ; 56(16): 2399-2402, 2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-31998888

RESUMEN

It is unprecedentedly found that ethylamine hydrochloride (EaCl) and phenol (PhOH) can form a new type of deep eutectic solvent (DES) with quite low viscosity. The strong hydrogen-bond donating abilities of EaCl and PhOH provide two active sites for robust interaction with NH3. Thus, the capacities of EaCl + PhOH DESs for NH3 absorption are notably high even at low pressures.

6.
J Agric Food Chem ; 62(14): 3293-3300, 2014 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-24655125

RESUMEN

Akebia trifoliata var. australis seed oil (ASO) was used as an edible oil in China. However, in-depth research studies on ASO have yet to be conducted for production of plastic fats in food industry. In this work, an immobilized lipase from Thermomyces lanuginosus (TL IM) was employed to catalyze palm stearin (PS) with different ratios of ASO in a laboratory-scale operation at 60 °C. The physical properties [e.g., fatty acid profile, slip melting point (SMP), solid fat content (SFC), polymorphic form, and microstructure] of physical blends (PBs) were analyzed and compared with those of the interesterified products (IPs). Results showed that SMPs of IPs (33.20-37.60 °C) decreased compared with those of PBs (48.03-49.30 °C). Meanwhile, IPs showed a good SFC range from 16.11% to 28.29% at 25 °C with mostly ß' polymorphic forms determined by X-ray diffraction analysis. It should be mentioned that no trans fatty acids (TFAs) were detected in any products, suggesting much more health-benefits of IPs. Texture tests showed that PBs (3318.19 ± 86.67 g) were markedly harder than IPs (557.02 ± 12.75 g). Conclusively, our study demonstrated that ASO can be utilized to produce trans-free plastic fats with good qualities through lipase-catalyzed interesterification.

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