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1.
Molecules ; 29(7)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38611845

RESUMEN

In this paper, berberine hydrochloride-loaded liposomes-in-gel were designed and developed to investigate their antioxidant properties and therapeutic effects on the eczema model of the mouse. Berberine hydrochloride-liposomes (BBH-L) as the nanoparticles were prepared by the thin-film hydration method and then dispersed BBH-L evenly in the gel matrix to prepare the berberine hydrochloride liposomes-gel (BBH-L-Gel) by the natural swelling method. Their antioxidant capacity was investigated by the free radical scavenging ability on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and H2O2 and the inhibition of lipid peroxides malondialdehyde (MDA). An eczema model was established, and the efficacy of the eczema treatment was preliminarily evaluated using ear swelling, the spleen index, and pathological sections as indicators. The results indicate that the entrapment efficiency of BBH-L prepared by the thin-film hydration method was 78.56% ± 0.7%, with a particle size of 155.4 ± 9.3 nm. For BBH-L-Gel, the viscosity and pH were 18.16 ± 6.34 m Pas and 7.32 ± 0.08, respectively. The cumulative release in the unit area of the in vitro transdermal study was 85.01 ± 4.53 µg/cm2. BBH-L-Gel had a good scavenging capacity on DPPH and H2O2, and it could effectively inhibit the production of hepatic lipid peroxides MDA in the concentration range of 0.4-2.0 mg/mL. The topical application of BBH-L-Gel could effectively alleviate eczema symptoms and reduce oxidative stress injury in mice. This study demonstrates that BBH-L-Gel has good skin permeability, excellent sustained release, and antioxidant capabilities. They can effectively alleviate the itching, inflammation, and allergic symptoms caused by eczema, providing a new strategy for clinical applications in eczema treatment.


Asunto(s)
Berberina , Eccema , Animales , Ratones , Antioxidantes/farmacología , Berberina/farmacología , Liposomas , Peróxido de Hidrógeno , Peróxidos Lipídicos
2.
Environ Geochem Health ; 46(4): 121, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483644

RESUMEN

Selective adsorption of heavy metal ions from industrial effluent is important for healthy ecosystem development. However, the selective adsorption of heavy metal pollutants by biochar using lignin as raw material is still a challenge. In this paper, the lignin carbon material (N-BLC) was synthesized by a one-step hydrothermal carbonization method using paper black liquor (BL) as raw material and triethylene diamine (TEDA) as nitrogen source. N-BLC (2:1) showed excellent selectivity for Cr(VI) in the binary system, and the adsorption amounts of Cr(VI) in the binary system were all greater than 150 mg/g, but the adsorption amounts of Ca(II), Mg(II), and Zn(II) were only 19.3, 25.5, and 6.3 mg/g, respectively. The separation factor (SF) for Cr(VI) adsorption was as high as 120.0. Meanwhile, FTIR, elemental analysis and XPS proved that the surface of N-BLC (2:1) contained many N- and O- containing groups which were favorable for the removal of Cr(VI). The adsorption of N-BLC (2:1) followed the Langmuir model and its maximum theoretical adsorption amount was 618.4 mg/g. After 5th recycling, the adsorption amount of Cr(VI) by N-BLC (2:1) decreased about 15%, showing a good regeneration ability. Therefore, N-BLC (2:1) is a highly efficient, selective and reusable Cr(VI) adsorbent with wide application prospects.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Adsorción , Carbono , Cromo/análisis , Concentración de Iones de Hidrógeno , Cinética , Lignina , Nitrógeno , Contaminantes Químicos del Agua/análisis
3.
Diabetologia ; 64(5): 1066-1078, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33687487

RESUMEN

AIMS/HYPOTHESIS: Glucagon-like peptide 1 receptor agonists (GLP-1 RA) such as exenatide are used as monotherapy and add-on therapy for maintaining glycaemic control in patients with type 2 diabetes mellitus. The current study investigated the safety and efficacy of once-weekly PB-119, a PEGylated exenatide injection, in treatment-naive patients with type 2 diabetes. METHODS: In this Phase II, randomised, placebo-controlled, double-blind study, we randomly assigned treatment-naive Chinese patients with type 2 diabetes in a 1:1:1:1 ratio to receive subcutaneous placebo or one of three subcutaneous doses of PB-119 (75, 150, and 200 µg) for 12 weeks. The primary endpoint was the change in HbA1c from baseline to week 12, and other endpoints were fasting plasma glucose, 2 h postprandial glucose (PPG), and proportion of patients with HbA1c < 53 mmol/mol (<7.0%) and ≤48 mmol/mol (≤6.5%) at 2, 4, 8 and 12 weeks of treatment. Safety was assessed in all patients who received at least one dose of study drug. RESULTS: We randomly assigned 251 patients to one of the four treatment groups (n = 62 in placebo and 63 each in PB-119 75 µg, 150 µg and 200 µg groups). At the end of 12 weeks, mean differences in HbA1c in the treatment groups were -7.76 mmol/mol (95% CI -9.23, -4.63, p < 0.001) (-0.72%, 95% CI -1.01, -0.43), -12.89 mmol/mol (95% CI -16.05, -9.72, p < 0.001) (-1.18%, 95% CI -1.47, -0.89) and -11.14 mmol/mol (95% CI -14.19, -7.97, p <0 .001) (-1.02%, 95% CI -1.30, -0.73) in the 75 µg, 150 µg and 200 µg PB-119 groups, respectively, compared with that in the placebo group after adjusting for baseline HbA1c. Similar results were also observed for other efficacy endpoints across different time points. There was no incidence of treatment-emergent serious adverse event, severe hypoglycaemia or death. CONCLUSIONS/INTERPRETATION: All tested PB-119 doses had superior efficacy compared with placebo and were safe and well tolerated over 12 weeks in treatment-naive Chinese patients with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT03520972 FUNDING: The study was funded by National Major Scientific and Technological Special Project for Significant New Drugs Development and PegBio.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Exenatida/uso terapéutico , Adolescente , Adulto , Anciano , Glucemia/efectos de los fármacos , Glucemia/metabolismo , China/epidemiología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Método Doble Ciego , Exenatida/química , Femenino , Hemoglobina Glucada/efectos de los fármacos , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Polietilenglicoles/química , Resultado del Tratamiento , Adulto Joven
4.
Appl Microbiol Biotechnol ; 97(24): 10309-20, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24196582

RESUMEN

Lignosulfonates(LSs), by-products from chemical pulping processes, are low-value products with limited dispersion properties. The ability of commercially available horseradish peroxidase (HRP) to polymerize LS macromolecules and improve the dispersion properties of LSs was investigated. The polymerization of LSs proceeded efficiently under mild reaction conditions in an aqueous solution with HRP/H2O2. Gel permeation chromatography showed a significant increase in weight-average molecular weight (M w ) of sulfonated kraft lignin and sodium lignosulfonate (NaLS) by 8.5-fold and 4.7-fold, respectively. The mechanism of polymerization was investigated by elemental analysis, surface charge measurement, headspace gas chromatography, infrared spectroscopy (IR), and hydrogen nuclear magnetic resonance spectrometry ((1)H-NMR). The functional group measurements indicated that HRP incubation did not reduce the sulfonic group content. However, it decreased the phenolic and methoxyl group contents. As the phenolic group content decreased, M w increased as a power function. The polymerization was proposed to involve the random coupling of phenoxy radical intermediates. The radicals coupled with each other to form different inter-unit linkages, most of which were the ß-O-4' type, as the (1)H-NMR spectra indicated. Moreover, the HRP/H2O2 incubation induced a significant improvement in the adsorption and dispersion properties of LSs. Therefore, the HRP/H2O2 incubation is a promising approach for industrial applications of LSs.


Asunto(s)
Peroxidasa de Rábano Silvestre/metabolismo , Peróxido de Hidrógeno/metabolismo , Lignina/análogos & derivados , Cromatografía de Gases , Cromatografía en Gel , Elementos Químicos , Lignina/química , Lignina/metabolismo , Espectroscopía de Resonancia Magnética , Peso Molecular , Polimerizacion , Espectrofotometría Infrarroja , Electricidad Estática
5.
Environ Sci Pollut Res Int ; 30(6): 14943-14958, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36161557

RESUMEN

Organic pollutants pose a serious threat to water environment, thus it is essential to develop high-performance adsorbent to remove them from wastewater. Herein, nitrogen-doped magnetic porous carbon (M-PLAC) with three-dimensional porous structure was synthesized from lignin to adsorb methylene blue (MB) and tetracycline (TC) in wastewater. The calculated equilibrium adsorption amount by M-PLAC for MB and TC was 645.52 and 1306.00 mg/g, respectively. The adsorption of MB and TC on M-PLAC conformed to the pseudo-second-order kinetic model. The removal of MB by M-PLAC showed fast and efficient characteristics and exhibited high selectivity for TC in a binary system. In addition, M-PLAC was suitable for a variety of complex water environments and had good regeneration performance, demonstrating potential advantages in practical wastewater treatment. The organic pollutant adsorption by M-PLAC was attributed to electrostatic interaction, hole filling effect, hydrogen bonding, and the π-π interaction.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Carbono , Lignina/química , Adsorción , Aguas Residuales , Porosidad , Nitrógeno , Tetraciclina/química , Antibacterianos , Agua/química , Fenómenos Magnéticos , Contaminantes Químicos del Agua/química , Cinética
6.
Environ Sci Pollut Res Int ; 29(7): 10467-10481, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34523095

RESUMEN

Cr(VI), a serious threat to human health, widely exists in the effluents of various industrial processes. In this paper, the potential of industrial lignin for efficient removal of Cr(VI) from wastewater was systematically investigated, including pulping black liquor lignin (BLN), enzymolysis lignin (ELN), and SPORL pretreatment spent liquor (FS). The structure characterizations of three lignins were investigated by thermogravimetry (TG), Fourier transform infrared (FTIR) spectroscopy, Brunauer-Emmett-Teller (BET) surface area measurement, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS). Among these three lignins, BLN showed the highest adsorption amount of Cr(VI) and good selectivity in wastewater simulation. According to the Langmuir model, the calculated maximum adsorption amount of Cr(VI) on ELN, BLN, and FS was 801.57, 864.30, and 642.26 mg g-1, respectively. The adsorption of Cr(VI) by industrial lignins was a chemisorption process, during which Cr(VI) was reduced to low-toxic Cr(III). This paper provided a promising application for the effective utilization of industrial lignins.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Adsorción , Cromo/análisis , Humanos , Concentración de Iones de Hidrógeno , Cinética , Lignina , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisis
7.
Int J Biol Macromol ; 159: 839-849, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32445824

RESUMEN

An environmentally friendly lignin-based composite (Lignin-PEI) was facilely prepared via cross-linking enzymatic hydrolysis lignin matrix and branched poly (ethylene imine). The specific physicochemical and structural properties of lignin-PEI were characterized by elemental analysis, N2 physisorption, GPC, TG, SEM, FT-IR and XPS. The nitrogen content of lignin-PEI was 9.02%, and the BET surface area was 20.32 m2/g. The synthetic composite showed high capacity and selectivity of Cr(VI) adsorption. The influence of solution pH, contact time, initial Cr(VI) concentration, and coexisting ions on Cr(VI) adsorption on lignin-PEI was systemically studied. The Cr(VI) adsorption on lignin-PEI was well described by the Langmuir model. According to the Langmuir model, the Cr(VI) adsorption capacity on lignin-PEI was as high as 898.2 mg/g at 318 K and pH 2.0. The calculated thermodynamic parameters, such as ΔG, ΔH, and ΔS, indicated the spontaneous and endothermic adsorption of Cr(VI) on lignin-PEI. The adsorption of Cr(VI) by lignin-PEI was following the pseudo-second-order kinetic model, indicating that it was a chemisorption process. The uptake mechanism was demonstrated to be electrostatic attraction, ion exchange, complexation and partial reduction. This work provided a promising candidate for Cr(VI) uptake with lignin-based biosorbents.


Asunto(s)
Cromo/química , Lignina/química , Adsorción , Algoritmos , Reactivos de Enlaces Cruzados/química , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termodinámica
8.
Bioresour Technol ; 310: 123389, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32335347

RESUMEN

A novel natural deep eutectic solvent (NDES) with water content ranging from 65 to 93 wt%, in which betaine (Bet) acts as the cation and amino acids (AAs) as the anions, was prepared by a simple and green chemical route. [Bet][AA] NDES showed excellent xylan and lignin solubility, however, scare cellulose solubility. A mild and facile pretreatment process with [Bet][AA] NDES was carried out at 60 °C for 5 h. The enzymatic hydrolysis efficiency of cellulose and corncob was significantly improved. Detailed characterization showed that the enhancement of cellulose digestibility derived mainly from xylan and lignin removal. Xylan and lignin removal for [Bet][Lys]-W87 was 47.68 and 49.06%, while it was 42.20% and 57.01% for [Bet][Arg]-W82, respectively. FT-IR, SEM, XRD, and HSQC NMR studies confirmed the effectiveness and mechanism of [Bet][Lys]-W87 and [Bet][Arg]-W82 on biomass pretreatment.


Asunto(s)
Betaína , Zea mays , Aminoácidos , Biomasa , Hidrólisis , Lignina , Solventes , Espectroscopía Infrarroja por Transformada de Fourier
9.
Int J Biol Macromol ; 154: 1194-1204, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31726153

RESUMEN

A lignin-based biosorbent (LSMA) was prepared by cross-linking lignosulfonate and N-methylaniline with the aid of ammonium persulfate for efficient removal of Cr(VI) from aqueous solution. Since LSMA possessed both amino groups and oxygen-containing functional groups, such as phenolic, carboxyl, and sulfonic groups, the maximum adsorption capacity of 1264.8 mg/g was achieved at 318 K according to the Langmuir isotherm. LSMA also showed excellent performance at low Cr(VI) concentration solution. The hazardous Cr(VI) solution of 50 mg/L can be fully removed within 10 min. The adsorption process of LSMA fitted the pseudo-second-order kinetic model, suggesting the chemical adsorption characteristics. Moreover, the adsorption process was spontaneous and endothermic. LSMA worked very well even with high content of competing anions. The removal mechanism was demonstrated to be the adsorption of Cr(VI) anions on LSMA with abundant functional groups, and reduction of Cr(VI) to less toxic Cr(III) by the adjacent electron donor groups. The generated Cr(III) was immobilized on LSMA by surface complexation and precipitation. LSMA composite has a great potential for the treatment of Cr(VI)-contaminated water.


Asunto(s)
Compuestos de Anilina/química , Cromo/química , Lignina/análogos & derivados , Contaminantes Químicos del Agua/química , Adsorción , Cinética , Lignina/química , Purificación del Agua
10.
J Agric Food Chem ; 67(22): 6248-6256, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31090409

RESUMEN

A lignin amphoteric surfactant and betaine could enhance the enzymatic hydrolysis of lignocellulose and recover cellulase. The effects of lignosulfonate quaternary ammonium salt (SLQA) and dodecyl dimethyl betaine (BS12) on enzymatic hydrolysis digestibility, ethanol yield, yeast cell viability, and other properties of high-solid enzymatic hydrolysis and fermentation of a corncob residue were studied in this research. The results suggested that SLQA and 1 g/L BS12 effectively improved the ethanol yield through enhancing enzymatic hydrolysis. SLQA had no significant effect on the yeast cell membrane and glucose fermentation. However, 5 g/L BS12 reduced the ethanol yield as a result of the fact that 5 g/L BS12 damaged the yeast cell membrane and inhibited the conversion of glucose to ethanol. Our research also suggested that 1 g/L BS12 enhanced the ethanol yield of corncob residue fermentation, which was attributed to the fact that lignin in the corncob adsorbed BS12 and decreased its concentration in solution to a safe level for the yeast.


Asunto(s)
Biotecnología/métodos , Celulosa/metabolismo , Etanol/química , Etanol/metabolismo , Lignina/metabolismo , Residuos/análisis , Levaduras/metabolismo , Zea mays/microbiología , Biocatálisis , Biotecnología/instrumentación , Celulasa/química , Fermentación , Glucosa/metabolismo , Hidrólisis , Lignina/química , Tensoactivos/química , Zea mays/metabolismo
11.
J Agric Food Chem ; 65(30): 6282-6287, 2017 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-28685577

RESUMEN

A biomimetic gastrointestinal tract, including in vitro digestion and biomimetic biomembrane extraction, has been proposed for absorption assessment of metals from edible plants. However, its validity is still unknown. Herein, two species of edible plants, Anoectochilus roxburghii and Radix astragali, were selected and digested in a bionic mouth, stomach, and intestine, and then trace metals (Cr, Mn, Fe, Ni, Cu, Zn, Se, Sr, As, and Pb) were transformed to their final metal species. To check model predictability, in vitro and in vivo metal absorption were imitated and tested by monolayer liposome extraction and rat stomach or single-pass duodenal intestine, respectively. A strong correlation was established between in vivo and in vitro metal absorption ratios, with 0.89 > R2 > 0.66, and a significant relationship (p < 0.05) was exhibited for stomach, intestine, two plant species, and 10 metal species. Our biomimetic system could be used as low-cost alternatives to animal and clinical studies for multi-metal absorption.


Asunto(s)
Medicamentos Herbarios Chinos/metabolismo , Tracto Gastrointestinal/metabolismo , Metales/metabolismo , Orchidaceae/metabolismo , Plantas Comestibles/metabolismo , Animales , Astragalus propinquus , Biomimética , Digestión , Medicamentos Herbarios Chinos/química , Tracto Gastrointestinal/química , Humanos , Absorción Intestinal , Metales/análisis , Orchidaceae/química , Ratas , Ratas Wistar
12.
Biotechnol Prog ; 30(5): 1076-83, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24930449

RESUMEN

The performances of five yeast strains under three levels of toxicity were evaluated using hydrolysates from lodgepole pine pretreated by Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses (SPORL). The highest level of toxicity was represented by the whole pretreated biomass slurry, while intermediate toxicity was represented by the hydrolysate with partial loading of pretreatment spent liquor. The zero toxicity was represented using the enzymatic hydrolysate produced from thoroughly washed SPORL lodgepole pine solids. The results indicate that strains D5A and YRH400 can tolerate the whole pretreated biomass slurry to produce 90.1 and 73.5% theoretical ethanol yield. Strains Y1528, YRH403, and FPL450 did not grow in whole hydrolysate cultures and were observed to have lower ethanol productivities than D5A and YRH400 on the hydrolysate with intermediate toxicity. Both YRH400 and YRH403 were genetically engineered for xylose fermentation but were not able to consume xylose efficiently in hydrolysate.


Asunto(s)
Etanol/metabolismo , Saccharomyces cerevisiae/metabolismo , Sulfitos/química , Biomasa , Reactores Biológicos/microbiología , Biotecnología , Etanol/análisis , Fermentación , Lignina/química , Lignina/metabolismo , Monosacáridos/metabolismo , Pinus/química , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/fisiología , Sulfitos/toxicidad
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