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1.
Chem Sci ; 14(31): 8401-8407, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37564418

RESUMEN

Herein, a triphenylamine derivative (TP-3PY) possessing 4-(4-bromophenyl)pyridine (PY) as an electron-accepting group and tris[p-(4-pyridylvinyl)phenyl]amine (TPA) with large two-photon absorption cross-sections as an electron-donating group was obtained, and showed intense absorption in the visible light region (λmax = 509 nm) and weak near-infrared (NIR) fluorescence emission at 750 nm. After complexation with cucurbit[8]uril (CB[8]), TP-3PY showed bright NIR fluorescence emission at 727 nm and phosphorescence emission at 800 nm. When the supramolecular assembly (TP-3PY⊂CB[8]) further interacted with dodecyl-modified sulfonatocalix[4]arene (SC4AD), the fluorescence and phosphorescence emissions were further enhanced at 710 and 734 nm, respectively. However, only the fluorescence emission of TP-3PY was enhanced in the presence of cucurbit[7]uril (CB[7]) and SC4AD. More interestingly, the photoluminescence of TP-3PY⊂CB[8]@SC4AD and TP-3PY⊂CB[7]@SC4AD assemblies could be excited by both visible (510 nm) and NIR light (930 nm). Finally, these ternary supramolecular assemblies with bright NIR light emission were applied to lysosome imaging of tumor cells and real-time biological imaging of mice.

2.
Ultrason Sonochem ; 85: 105993, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35367738

RESUMEN

High intensity ultrasound (HIU) is an efficient and green technology that has recently received enormous research attention for modification of food proteins. However, there are still several knowledge gaps in the possible mechanisms, synergistic effects of HIU with other strategies and improvement of HIU equipment that contribute to its application in the food industry. This review focuses on the recent research progress on the effects and potential mechanisms of HIU on the structure (including secondary and tertiary structure) and functionality (including solubility, emulsibility, foamability, and gelability) of proteins. Furthermore, the combination methods and innovations of HIU equipment for proteins modification in recent years are also detailed. Meanwhile, the possible future trends of food proteins modification by HIU are also considered and proposed.


Asunto(s)
Solubilidad
3.
Food Chem ; 366: 130600, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34311237

RESUMEN

The effect of dual-frequency sequential ultrasonic thawing (DUT) on the quality of quick-frozen small yellow croaker was studied by TMT-labeled quantitative proteomic method. A total number of 75 proteins were identified as differentially abundant proteins (DAPs) in fish meat treated by DUT, while 72 DAPs were in flow water thawing (FWT). The Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis indicated that the DAPs in the significant enrichment pathway of DUT group were enzymes. Compared with FWT, DUT had a significant effect on the enzyme content. The correlation analyses indicated that 40 DAPs were related with the quality traits. The 11 highly correlated DAPs are expected to be used as potential protein markers for texture profile analyses, color, thawing loss, water-holding capacity, and pH of thawed small yellow croaker quality. These results provide a further understanding of the quality stability of quick-frozen small yellow croaker treated by the DUT.


Asunto(s)
Perciformes , Proteómica , Animales , Peces , Genoma , Carne , Perciformes/genética
4.
Acta Pharmacol Sin ; 42(11): 1930-1941, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34462563

RESUMEN

Intracellular Staphylococcus aureus (S. aureus) often causes clinical failure and relapse after antibiotic treatment. We previously found that 20(S)-ginsenoside Rh2 [20(S)-Rh2] enhanced the therapeutic effect of quinolones in a mouse model of peritonitis, which we attributed to the increased concentrations of quinolones within bacteria. In this study, we investigated the enhancing effect of 20(S)-Rh2 on levofloxacin (LVF) from a perspective of intracellular bacteria. In S. aureus 25923-infected mice, coadministration of LVF (1.5 mg/kg, i.v.) and 20(S)-Rh2 (25, 50 mg/kg, i.g.) markedly increased the survival rate, and decreased intracellular bacteria counts accompanied by increased accumulation of LVF in peritoneal macrophages. In addition, 20(S)-Rh2 (1, 5, 10 µM) dose-dependently increased the uptake and accumulation of LVF in peritoneal macrophages from infected mice without drug treatment. In a model of S. aureus 25923-infected THP-1 macrophages, we showed that 20(S)-Rh2 (1, 5, 10 µM) dose-dependently enhanced the intracellular antibacterial activity of LVF. At the cellular level, 20(S)-Rh2 increased the intracellular accumulation of LVF by inhibiting P-gp and BCRP. PK-PD modeling revealed that 20(S)-Rh2 altered the properties of the cell but not LVF. At the subcellular level, 20(S)-Rh2 did not increase the distribution of LVF in lysosomes but exhibited a stronger sensitizing effect in acidic environments. Molecular dynamics (MD) simulations showed that 20(S)-Rh2 improved the stability of the DNA gyrase-LVF complex in lysosome-like acidic conditions. In conclusion, 20(S)-Rh2 promotes the cellular pharmacokinetics and intracellular antibacterial activities of LVF against S. aureus through efflux transporter inhibition and subcellular stabilization, which is beneficial for infection treatment.


Asunto(s)
Antibacterianos/farmacocinética , Ginsenósidos/farmacocinética , Líquido Intracelular/metabolismo , Levofloxacino/farmacocinética , Staphylococcus aureus/metabolismo , Fracciones Subcelulares/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Femenino , Humanos , Líquido Intracelular/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos ICR , Pruebas de Sensibilidad Microbiana/métodos , Staphylococcus aureus/efectos de los fármacos , Fracciones Subcelulares/efectos de los fármacos , Células THP-1
5.
Ultrason Sonochem ; 70: 105352, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32979636

RESUMEN

The influence of multi-frequency combined ultrasound thawing on primary, secondary, and tertiary structures, electrophoresis pattern, particle size distribution, zeta potential values, thermal stability, rheological behavior, and microstructure of small yellow croaker myofibrillar proteins (MPs) were studied. Four treatments were used for thawing small yellow croakers: flow water thawing (FWT), mono-frequency ultrasonic thawing (MUT), dual-frequency ultrasonic thawing (DUT), and tri-frequency ultrasonic thawing (TUT). Compared with fresh samples (FS), the MPs of the sample pretreated by DUT had non-significant effect on protein primary (including free amino groups and surface hydrophobicity), secondary, tertiary structures, electrophoresis pattern, and microstructure. MPs pretreated by DUT had less aggregation and degradation. Besides, DUT treatment increased the thermal stability of MPs. The ultrasound had significant effects on the rheological properties of MPs. Overall, DUT effectively minimized the changes in MPs structure and protected the protein thermal stability and rheological behavior during the thawing process.


Asunto(s)
Proteínas Musculares/química , Reología , Sonicación/métodos , Animales , Perciformes , Conformación Proteica
6.
Front Psychol ; 11: 1555, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32765356

RESUMEN

Reaction-time variability is a critical index of sustained attention. However, researchers still lack effective measures to establish the association between neurophysiological activity and this behavioral variability. Here, the present study recorded reaction time (RT) and cortical electroencephalogram (EEG) in healthy subjects when they continuously performed an alternative responding task. The frontal theta activity and reaction-time variability were examined trial by trial using the measures of standard deviation (SD) in the time domain and amplitude of low-frequency fluctuation (ALFF) in the frequency domain. Our results showed that the SD of reaction-time variability did not have any correlation with the SD of trial-by-trial frontal theta activity, and the ALFF of reaction-time variability has a significant correlation with the ALFF of trial-by-trial frontal theta activity in 0.01-0.027 Hz. These results suggested the methodological significance of ALFF in establishing the association between neurophysiological activity and reaction-time variability. Furthermore, these findings also support the low-frequency fluctuation as a potential feature of sustained attention.

7.
Dalton Trans ; 49(4): 998-1001, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31930274

RESUMEN

Reversible single crystal-to-single crystal transformations from [FeL2(NCS)2]·3MeOH (1·3MeOH, L = 2-(anthracen-10-yl)-1H-imidazo[4,5-f][1,10]phenanthroline) to 1 and 1·2H2O were reported, which were accompanied by on-off switching of the spin-crossover properties.

8.
Huan Jing Ke Xue ; 40(11): 4944-4952, 2019 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-31854560

RESUMEN

The construction of the Three Gorges Reservoir has had certain effects on the ecological environment of the water and serious phytoplankton blooms have occurred in its tributary embayment. To explore the spatial distribution of nitrogen and phosphorus nutrients and chlorophyll-a in different tributaries of the Three Gorges Reservoir, a water quality study (June 2018) was conducted in the Xiangxi River, Shengnongxi River, and Daning River of the Three Gorges Reservoir. The results showed that the average TN in the three tributaries was 1.86 mg·L-1, 1.90 mg·L-1, and 1.43 mg·L-1, respectively, and average TP was 0.09 mg·L-1, 0.07 mg·L-1, and 0.05 mg·L-1, respectively. Single-factor ANOVA analysis showed that the spatial difference in TN was significant and occurred in the following order:Shennongxi River > Xiangxi River > Daning River. There were significant differences in the spatial distribution of TP, which were in the order off Xiangxi River > Shennongxi River > Daning River. The mean concentrations of chlorophyll-a in the three tributaries was 6.41 µg·L-1, 21.39 µg·L-1, and 9.85µg·L-1, respectively. The results from the Pearson correlation analysis, showed that chlorophyll-a concentrations were closely related to TP distribution in all tributaries, but Zeu/Zmix was also correlated with the distribution of chlorophyll-a in the Shennongxi River and Daning River. The ratio of TN and TP concentrations was 22.36, 26.76, and 28.6, respectively, which revealed that TP is a critical and limiting factor affecting phytoplankton growth in its tributary embayment.


Asunto(s)
Clorofila A , Ríos , Sales (Química) , China , Clorofila , Monitoreo del Ambiente , Eutrofización , Inundaciones , Nitrógeno , Nutrientes , Fósforo , Estaciones del Año
9.
Huan Jing Ke Xue ; 40(8): 3530-3538, 2019 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-31854758

RESUMEN

After the construction of the Xiangjiaba Dam, the hydrodynamic conditions, nutrient distributions, and transport conditions of the Jinsha River were changed. Here, the nutrient distribution characteristics and retention effects of Xiangjiaba Reservoir were investigated according to the results of water quality monitoring from 2015 to 2016. Spatial and temporal variations in TN, TP, SiO32-Si, and other nutrients, and retention flux and retention rate were analyzed. The results showed that the nutrient mass concentration of TN, TP, and SiO32--Si was 0.905 mg·L-1, 0.034 mg·L-1, and 7.98 mg·L-1, respectively. The distribution of TN was affected by point sources and the concentration of TN was large in urban areas. This distribution of TP was mainly granular and the mass concentrations decreased along the river path. The mass concentration of SiO32--Si did not significantly vary over time and space. Furthermore, Xiangjiaba Reservoir had a persistent effect on nutrient salts; the average annual retention of TN, TP, and SiO32--Si was 2.30×104 t·a-1, 0.146×104 t·a-1, and -2.4×104 t·a-1, respectively. During different seasons, the retention of TN and SiO32--Si varied between positive or negative; however, TP appeared to be consistent. The average monthly retention efficiency of TN, TP, and SiO32--Si was 17.5%, 32.8%, and -2.14%, respectively. Overall, retention efficiencies were higher during the dry season than that wet season, and phosphorus retention was most pronounced. The retention of TN in the reservoir may be related to denitrification and the input of external load; the flux of SiO32--Si was mainly affected by runoff; and the particle morphology of phosphorus, as well as reservoir period, were the main factors affecting TP retention. There were no clear correlations between nutrient retention and the mass concentrations of TN and SiO32--Si, but the nutrient retention effect of Xiangjiaba Reservoir reduced TP concentrations along the river path and increased TP concentration with vertical depth.

10.
BMC Cardiovasc Disord ; 19(1): 233, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31640555

RESUMEN

BACKGROUND: Ventricular arrhythmias (VAs) arising from the origin above pulmonary valve lack comprehensive investigation. This study aimed to disclose the characteristics and radiofrequency catheter ablation (RFCA) outcomes for those VAs. METHODS: One hundred six VAs arising from the region above pulmonary valve treated with RFCA were included in this study. RESULTS: Seventy-five cases were identified in the pulmonary sinus cusps (PSCs, 32 in left sinus cusp (PLC), 15 in right (PRC), 28 in anterior (PAC)) and 31 cases were in the main stem of pulmonary artery (MSPA, 18 above PLC (LMSPA), 3 above PRC (RMSPA), 10 above PAC (AMSPA)). Compared with PSCs VAs, MSPA VAs exhibited a higher R wave amplitude in the inferior leads, a total inferior R amplitude > 5.1 mV predicting MSPA origins. LMSPA, RMSPA and AMSPA VAs resembled PLC, PRC and PAC VAs in electrocardiographic characteristics respectively. No electrophysiological differences were found between PSCs and MSPA VAs. The irrigated-up catheter and R0 Swartz long sheath were more utilized for ablation of PSCs VAs than for MSPA VAs. All these VAs were successfully eliminated by RFCA. CONCLUSION: VAs arising from the origin above pulmonary valve were common. Based on certain electrocardiographic characteristics, they could be roughly located, which contributed to an effective RFCA.


Asunto(s)
Ablación por Catéter , Arteria Pulmonar/cirugía , Válvula Pulmonar , Taquicardia Ventricular/cirugía , Complejos Prematuros Ventriculares/cirugía , Adulto , Ablación por Catéter/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/fisiopatología , Válvula Pulmonar/diagnóstico por imagen , Estudios Retrospectivos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatología , Resultado del Tratamiento , Complejos Prematuros Ventriculares/diagnóstico , Complejos Prematuros Ventriculares/fisiopatología
11.
Chemistry ; 25(66): 15173-15181, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-31544301

RESUMEN

Owing to low ion/electron conductivity and large volume change, transitional metal dichalcogenides (TMDs) suffer from inferior cycle stability and rate capability when used as the anode of lithium-ion batteries (LIBs). To overcome these disadvantages, amorphous molybdenum sulfide (MoSx ) nanospheres were prepared and coated with an ultrathin carbon layer through a simple one-pot reaction. Combining X-ray photoelectron spectroscopy (XPS) with theoretical calculations, MoSx was confirmed as having a special chain molecular structure with two forms of S bonding (S2- and S2 2- ), the optimal adsorption sites of Li+ were located at S2 2- . As a result, the MoSx electrode exhibits superior cycle and rate capacities compared with crystalline 2H-MoS2 (e.g., delivering a high capacity of 612.4 mAh g-1 after 500 cycles at 1 A g-1 ). This is mainly attributed to more exposed active S2 2- sites for Li storage, more Li+ transfer pathways for improved ion conductivity, and suppressed electrode structure pulverization of MoSx derived from the inherent chain-like molecular structure. Quantitative charge storage analysis further demonstrates the improved pseudocapacitive contribution of amorphous MoSx induced by fast reaction kinetics. Moreover, the morphology contrast after cycling demonstrates the dispersion of active materials is more uniform for MoSx than 2H-MoS2 , suggesting the MoSx can well accommodate the volume stress of the electrode during discharging. Through regulating the molecular structure, this work provides an effective targeted strategy to overcome the intrinsic issues of TMDs for high-performance LIBs.

12.
Food Funct ; 10(9): 5574-5586, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31432066

RESUMEN

The antidiabetic activity and potential underlying mechanism of a polysaccharide-protein (PSP) complex from Corbicula fluminea were determined in streptozotoxin (STZ)-induced diabetic rats. PSP exhibited inhibitory activity (in vitro) against α-glucosidase and α-amylase via a reversible competitive inhibition pattern with a stronger inhibition for α-glucosidase. Dietary administration of PSP had potential antidiabetic activities in vivo, which was evidenced by the fact that PSP alleviates body weight loss and organ injuries, reduced fasting blood glucose levels, elevated glucose tolerance, and ameliorated lipid metabolism and hepatic functions, as well as attenuated oxidative stress in STZ-treated diabetic rats. Furthermore, our results demonstrated that the antidiabetic activities of PSP were associated with the activation of the phosphoinositide 3-kinase/protein kinase B signaling pathway in STZ-treated rats. These findings supported the potential of PSP to be used as a functional ingredient in the preparation of functional and medicinal foods to inhibit diabetes mellitus and its complications.


Asunto(s)
Corbicula/química , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Polisacáridos/administración & dosificación , Proteínas/administración & dosificación , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Experimental/metabolismo , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Estrés Oxidativo/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Estreptozocina , alfa-Glucosidasas/metabolismo
13.
Chemistry ; 25(38): 8975-8981, 2019 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-31021424

RESUMEN

Lithium-ion batteries (LIBs) are one of the most significant energy storage devices applied in power supply facilities. However, a huge number of spent LIBs would bring harmful resource waste and environmental hazards. In this study, a benign hydrometallurgical method using phytic acid as precipitant is proposed to recover useful metallic Mn ions from spent LiMn2 O4 batteries. Besides Mn-based cathodes, this recovery process is also applicable for other commercial batteries. More importantly, for the first time, the as-obtained manganous complex is employed as a nanofiller in a polyethylene oxide matrix to largely improve Li+ conductivity and transference number. As a result, when applied in all-solid-state lithium batteries, high capacity and outstanding cyclic stability are achieved with capacity retention of 86.4 % after 60 cycles at 0.1 C. The recovery of spent lithium batteries not only has benefits for the environment and resources, but also shows great potential application in all-solid-state lithium batteries, which opens up a costless and efficient circulation pathway for clean and reliable energy storage systems.

14.
Int J Biol Macromol ; 131: 941-948, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30914364

RESUMEN

In this study, a three-phase partitioning (TPP) system with dimethyl carbonate (DMC) as organic phase and sodium citrate (SC) as salt phase was used for partitioning of exopolysaccharide (EPS), namely, EPS-D, from fermentation broth of Phellinus baumii. Results showed that the maximum extraction yield (EY) of EPS-D was 71.02% under the following modified optimal conditions: DMC to fermentation broth ratio 0.5:1.0 (v/v), SC concentration 19% (w/v), temperature 30 °C, and pH 4.0. EPS-D had higher EY, carbohydrate, and uronic acid contents compared with the EPS, designated as EPS-T, obtained from the TPP system with t-butanol and ammonium sulfate. EPS-D and EPS-T had different chemical compositions and molecular weights; however, their preliminary chemical structures basically remained unchanged. Moreover, EPS-D exhibited stronger free radical-scavenging capability and total antioxidant capacity than EPS-T. Therefore, the TPP system with DMC as an alternative solvent for t-butanol has great potential for efficient partitioning of natural biomolecules.


Asunto(s)
Basidiomycota/química , Formiatos/química , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/aislamiento & purificación , Extracción Líquido-Líquido , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Basidiomycota/metabolismo , Fenómenos Químicos , Fermentación , Polisacáridos Fúngicos/farmacología , Concentración de Iones de Hidrógeno , Solventes , Análisis Espectral , Temperatura
15.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(5): 414-417, 2019 Sep.
Artículo en Chino | MEDLINE | ID: mdl-31894672

RESUMEN

OBJECTIVE: To investigate the effects of apolipoprotein E (apoE) on the proliferation of pulmonary arterial smooth muscle cells (PASMCs) induced by hypoxia. METHODS: Primary culture of mouse PASMCs was prepared from male C57BL/6 mouse pulmonary artery by the method of tissue block anchorage. PASMCs were divided into four groups: normoxia group, normoxia with apoE administration group, hypoxia group and hypoxia with apoE administration group. The proliferation of PASMCs was observed by EdU incorporation. The protein levels of apoE, proliferating cell nuclear antigen (PCNA), protein kinase C (PKC) and phosphorylated protein kinase C (p-PKC) were analyzed by Western blot. RESULTS: The percentage of PASMCs proliferation of hypoxia group was significantly higher than that of normoxia group by 64.7% (P<0.05), and the protein expression levels of PCNA and p-PKC of hypoxia group were up-regulated than those of normoxia group by 69.0% and 120.0%, while the protein expression of apoE was down-regulated by 51.0% (P<0.05), respectively. The percentage of PASMCs proliferation of hypoxia with apoE administration group was significantly lower than that of hypoxia group by 19.6% (P<0.05), and the protein expression levels of PCNA and p-PKC of hypoxia with apoE administration group were down-regulated than those of hypoxia group by 19.8% and 103.2% (P<0.05), respectively. There was no significant difference among each group in the protein expression of PKC, nor do there any significant difference between normoxia group and hypoxia group in the protein expression of p-PKC (P>0.05). CONCLUSION: ApoE can inhibit the proliferation of PASMCs induced by hypoxia, and the mechanism of its effect may be attributed to blocking PKC pathway.


Asunto(s)
Apolipoproteínas E , Hipertensión Pulmonar , Miocitos del Músculo Liso , Arteria Pulmonar , Animales , Apolipoproteínas E/farmacología , Hipoxia de la Célula/fisiología , Proliferación Celular , Células Cultivadas , Masculino , Ratones , Ratones Endogámicos C57BL , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/efectos de los fármacos
16.
Int J Biol Macromol ; 123: 201-209, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30439423

RESUMEN

In this study, three-phase partitioning (TPP) was used to directly extract and separate bioactive exopolysaccharides (EPSs) from a cultured broth of Phellinus baumii. The maximum extraction yield of EPS was 52.09% under the following optimal conditions: 20% (w/v) ammonium sulfate concentration, 1.0:1.5 (v/v) ratio of cultured broth to t­butanol, 30 min, and 35 °C. A multifrequency power ultrasound in a sequential mode coupled with TPP resulted in ~9.12% increment in extraction yield and ~80% reduction in extraction time compared with those of traditional TPP. The carbohydrate (88.21%) and uronic acid (3.37%) contents of partially purified EPS were higher than those of EPS-C obtained through conventional ethanol precipitation and separation methods. EPS and EPS-C exhibited similar preliminary structural characteristics and different monosaccharide compositions and molecular weights. The radical-scavenging abilities, antioxidant capacities, α­amylase and α­glycosidase inhibitory activities, and macrophage stimulation activities of EPS were also higher than those of EPS-C. Therefore, it could be concluded that TPP as a simple and green separation technique could be used to directly extract and separate bioactive EPS from the fermentation broths of mushrooms and other fungi.


Asunto(s)
Antioxidantes/aislamiento & purificación , Carbohidratos/aislamiento & purificación , Polisacáridos/aislamiento & purificación , Sulfato de Amonio/química , Antioxidantes/química , Antioxidantes/farmacología , Basidiomycota/química , Carbohidratos/química , Carbohidratos/farmacología , Fermentación , Macrófagos/efectos de los fármacos , Peso Molecular , Polisacáridos/química , Polisacáridos/farmacología , Ácidos Urónicos/química , alfa-Amilasas/antagonistas & inhibidores , alfa-Glucosidasas/efectos de los fármacos
17.
Colloids Surf B Biointerfaces ; 170: 692-700, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29986266

RESUMEN

Selenium nanoparticles (SeNPs) as a new replacement source of other Se forms applied in nutritional supplements have been associated with health-related issues. Pectin (PEC) as a well-known food-grade polysaccharide has been considered as a potential soft template for the preparation and stabilization of SeNPs in aqueous medium. In this study, therefore, PEC was used as a stabilizer and dispersing agent to form well-dispersed and stable SeNPs under a simple redox system of selenite and ascorbic acid. Se/PEC ratios significantly affected the color of the suspension, particle size, and surface morphology of the as-prepared SeNPs in the presence of PEC. PEC-SeNPs with a Se/PEC ratio of 1:2 appeared amorphous and exhibited a well-dispersed and stable spherical structure with an average size of ∼41 nm, which corresponds to the strong hydrogen bonding between the hydroxyl groups of PEC and SeNPs. The PEC-SeNPs (Se/PEC = 1:2) remained highly stable in different acidic solutions for at least 1 month. Small and highly stable PEC-SeNPs (Se/PEC = 1:2) possessed the strongest DPPH radical scavenging ability and antioxidant capacity among the evaluated PEC-SeNPs. They also possessed a low cytotoxic activity against cancer cells (SPCA-1 and HeLa) and normal cells (RWPE-1) in vitro. These findings suggested that pectin as a surface decorator could be effectively used to improve the stability and antioxidant capacity of SeNPs remarkably.


Asunto(s)
Antioxidantes/farmacología , Nanopartículas/química , Pectinas/farmacología , Compuestos de Selenio/farmacología , Antioxidantes/química , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Tamaño de la Partícula , Pectinas/química , Compuestos de Selenio/química , Relación Estructura-Actividad , Propiedades de Superficie
18.
Carbohydr Polym ; 193: 373-382, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29773393

RESUMEN

In this study, hot water, 0.9% NaCl, citric acid, and 1.25 M NaOH/0.05% NaBH4 were separately used for the extraction of water-soluble H. erinaceus polysaccharides (HEPs; HEP-W, HEP-S, HEP-C, and HEP-A) from the fruit body of Hericium erinaceus. The physicochemical properties and biological activities were then investigated and compared. Results showed that the extraction solvents exhibited significant effects on the extraction yields, molecular weights, monosaccharide compositions, preliminary structural characteristics, microstructures of HEPs and on their contents, such as neutral sugar, uronic acid, protein, and ß-(1 → 3)-glucan. In vitro antioxidant activity assays indicated that HEP-C extracted with citric acid solution showed stronger scavenging abilities on hydroxyl and DPPH radicals and antioxidant capacities than HEP-W and HEP-S. Moreover, HEP-C exhibited the strongest inhibitory effects on α-glycosidase and α-amylase activities. Therefore, HEP-C extracted with citric acid can be developed as a potential bioactive ingredient for applications in food, medicine, and cosmetics industries.

19.
Ultrason Sonochem ; 40(Pt A): 128-134, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28946406

RESUMEN

Ultrasound and three-phase partitioning (USTPP) were combined to extract and separate polysaccharides (PS) efficiently from Corbicula fluminea crude extracts. The following optimum experimental conditions were established: 20% (w/v) ammonium sulfate concentration, 1:1 (v/v) t-butanol to crude extract ratio, 180W ultrasonic power, 40kHz frequency, 100% duty cycle, 10min irradiation time, and 35°C. The maximum extraction yield of PS obtained from USTPP was approximately 11.22%, which was higher than the maximum yields from conventional three-phase partitioning (TPP; 9.32%) and ultrasound extraction (USE; 6.05%). The extraction time for USTPP was significantly reduced to 10min from 30 and 60min for TPP and USE methods, respectively. The primary chemical structures of PS collected through the three extraction protocols were basically conserved. The synergistic effects of ultrasound and TPP on PS extraction were also determined. Results revealed that USTPP is an effective technique to extract and separate PS from C. fluminea potentially applied in food, cosmetics, and medicines.


Asunto(s)
Fraccionamiento Químico/métodos , Corbicula/química , Polisacáridos/aislamiento & purificación , Ondas Ultrasónicas , Sulfato de Amonio/química , Animales , Polisacáridos/química , Temperatura , Factores de Tiempo , Alcohol terc-Butílico/química
20.
Int J Biol Macromol ; 107(Pt A): 397-405, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28882758

RESUMEN

In this study, negatively charged carboxylic curdlan (Cc) bearing a ß-1,3-polyglucuronic acid structure was employed to fabricate nanosized polyelectrolyte complexes (PECs) with positively charged chitosan (CS) in aqueous solution as potential carriers for 5-fluorouracil (5Fu) delivery. Nanosized CS/Cc PECs were formed by the addition of 0.5mg/mL solutions of CS and Cc with a mixing ratio of 1:1 (w/w) at pH 3.0. Under optimized conditions, the prepared CS/Cc PECs showed spherical morphology with an average size of about 180nm and a zeta potential of around 41mV. The 5Fu drug was incorporated into the nanosized CS/Cc PECs and showed excellent encapsulation efficiency (86.47%) and loading content (10.81%). The drug release data in vitro indicated that the nanosized CS/Cc PECs are promising carriers for the sustained release of 5Fu with an anomalous transport mechanism following the Ritger-Peppas model. Besides, the CS/Cc PECs exhibited low cytotoxic activity against SPCA-1 and HeLa cell lines in vitro. This finding suggested that the development of the nanosized CS/Cc PECs offered great promise as an antitumor drug platform.


Asunto(s)
Quitosano/química , Fluorouracilo/química , Nanopartículas/química , Polielectrolitos/química , Quitosano/síntesis química , Quitosano/farmacología , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Fluorouracilo/farmacología , Células HeLa , Humanos , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Polielectrolitos/síntesis química , Polielectrolitos/farmacología , beta-Glucanos/química
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