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1.
Phytomedicine ; 98: 153919, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35104757

RESUMEN

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD), characterized by hepatic steatosis and hepatocyte injury, is an obesity-induced metabolic dysregulation with few available therapeutic options. Enhancement of the mitochondrial function was considered as an effective treatment for NALFD. Unsaturated fatty acids (UFAs) have been shown to have beneficial effects on metabolic syndrome disease such as hyperlipidemia, coronary artery disease and cardiovascular diseases. The seed oil of Rosa roxburghii Tratt (ORRT) was of high quality in terms of its high amount of unsaturated fatty acids. However, the effects of ORRT on NALFD have not been reported so far. PURPOSE: The study aimed to evaluate the protective effects and molecular mechanism of ORRT for the treatment of NAFLD in vivo and in vitro. METHODS: The beneficial effects, especially improving the mitochondrial function, and the potential mechanism of ORRT on NAFLD were studied both in vivo and in vitro. Lipid levels were determined by triglyceride (TG), total cholesterol (TC), and Oil Red O staining. Oxidative stress and inflammation were assessed by detecting antioxidant enzyme activity, MDA content, and ELISA assay. Blood TG, TC, HDL-c and LDL-c levels were measured in HFD mice. Western blot analyses were used to determine the levels of the protein involved in fatty acid oxidation, oxidative metabolism, and mitochondria biogenesis and function. The mitochondrial membrane potential level was measured by JC-1 staining to teste the effect of ORRT on mitochondrial function in vitro. GW6471 (inhibitor of PPARα) was used to confirm the relationship between PPARα and PGC-1α. RESULTS: ORRT significantly restrained NAFLD progression by attenuating lipid accumulation, oxidative stress and inflammatory response. Furthermore, ORRT upregulated thermogenesis-related gene expressions, such as uncoupling protein 1 (UCP1) and p38 mitogen-activated protein kinase (p38 MAPK). The results showed that the expression of key genes involved in fatty acid oxidation (e.g., CPT-1α, ACADL, PPARα) and in mitochondrial biogenesis and function (e.g., TFAM, NRF1, PGC-1α, and COX IV) was significantly increased. Together with the observed MMP improvement, these findings suggested that ORRT activated the mitochondrial oxidative pathway. Additionally, GW6471 inhibited the ORRT on promoting the expression of PGC-1α, CPT-1α, and ACADL. In conclusion, ORRT possessed the potential to prevent lipid accumulation via the PPARα/PGC-1α signaling pathway, which could be developed as a natural health-promoting oil against NAFLD.

2.
Ying Yong Sheng Tai Xue Bao ; 31(7): 2251-2256, 2020 Jul.
Artículo en Chino | MEDLINE | ID: mdl-32715688

RESUMEN

Velvetleaf (Abutilon theophrasti) is a common weed in dryland, which can reduce crop yield. Allelopathy is one of the possible reasons resulting in crop yield reduction. In this study, we analyzed the allelopathic effect of velvetleaf volatile oil components on germination and seedling growth of three dryland crops, wheat (Triticum aestivum), maize (Zea mays), and soybean (Glycine max). A total of 26 compounds in velvetleaf volatile oil were identified by GC-MS, accounting for 98.1% of the total chromatographic peak areas. The terpenes with lower molecular weight in the volatile oil were α-pinene, eucalyptol, α-terpinolene, ß-terpinene, trans-α-ionone, and trans-ß-ionone. The saturated aqueous solution of velvetleaf volatile oil could inhibit seed germination of three crops by filter paper and soil. Velvetleaf volatile oil could inhibit the seedling growth of three crops through air, filter paper, and soil. Wheat was the most susceptible to volatile oil, followed by maize and soybean. The inhibitory effect of volatile oil on the growth of wheat was the strongest in air medium, followed by filter paper and soil medium. The lower molecular weight of terpene components from volatile oil might be the important allelochemicals.


Asunto(s)
Aceites Volátiles , Zea mays , Alelopatía , Germinación , Plantones , Glycine max , Triticum
3.
Int Immunopharmacol ; 83: 106436, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32234671

RESUMEN

Phenolic acids are found in natural plants, such as caffeic acid, rosmarinic acid, and chlorogenic acid. They have long been used as pharmacological actives, owing to their anti-inflammatory and antioxidant activities. Cryptochlorogenic acid (CCGA) is a special isomer of chlorogenic acid; the pharmacological effects and related molecular mechanisms of CCGA have been poorly reported. In the present study, the antioxidant and anti-inflammatory effects of CCGA in RAW 264.7 macrophages and the underlying mechanisms were investigated. The results revealed that CCGA dose-dependently inhibited LPS-induced production of NO, TNF-α, and IL-6 and blocked iNOS, COX-2, TNF-α, and IL-6 expressions. CCGA also significantly increased the GSH/GSSG ratio and SOD activity and reduced the MDA level. Moreover, CCGA suppressed the nuclear translocation of NF-κB by hindering the phosphorylation of IκB kinase (IKK) and degrading IκB. It also downregulated the phosphorylation of MAPKs. Our results indicated that CCGA significantly inhibited NF-κB activation by controlling the expression of pro-inflammatory factors and promoting the nuclear transfer of Nrf2. In conclusion, CCGA could attenuate LPS-induced inflammatory symptoms by modulating NF-κB/MAPK signaling cascades and inhibit LPS-induced oxidative stress via Nrf2 nuclear translocation.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Ácido Clorogénico/análogos & derivados , Hemo-Oxigenasa 1/metabolismo , Macrófagos/metabolismo , Proteínas de la Membrana/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Animales , Ácido Clorogénico/farmacología , Quinasa I-kappa B/metabolismo , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Mediadores de Inflamación/antagonistas & inhibidores , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Ratones , FN-kappa B/efectos de los fármacos , FN-kappa B/metabolismo , Células RAW 264.7 , Transducción de Señal/efectos de los fármacos
4.
Food Chem ; 212: 403-10, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27374549

RESUMEN

Cavitation-accelerated aqueous enzymatic extraction (CAEE) of seed oil from Cucurbita pepo was performed. An enzyme cocktail comprised of cellulose, pectinase and proteinase can work synergistically in releasing the oil. The CAEE extraction conditions were optimized by a Plackett-Burman design followed by a central composite methodology. A maximal extraction yield of 58.06% was achieved under optimal conditions of vacuum degree -0.07, enzyme amount 1.05% and extraction time 69min. As compared to soxhlet extraction (SE)-derived oil, CAEE-derived oil exhibited similar physical properties and better oxidation stability. In addition, chemical composition analyzing showed that the content of linoleic acid obtained by CAEE (47.67%) was higher than that of SE (44.51%). Moreover, the IC50 of oil obtained by CAEE and SE, as measured by α-amylase inhibition assay, were 40.68µg/mL and 45.46µg/mL. All results suggest that CAEE represents an excellent alternative protocol for production of oil from oil-bearing materials.


Asunto(s)
Cucurbita , Cromatografía de Gases y Espectrometría de Masas/métodos , Hipoglucemiantes/análisis , Aceites de Plantas/análisis , Semillas/química , Agua/análisis , Hipoglucemiantes/farmacología , Ácido Linoleico/análisis , Extracción Líquido-Líquido/métodos , Oxidación-Reducción , Aceites de Plantas/farmacología , alfa-Amilasas/análisis , alfa-Amilasas/antagonistas & inhibidores
5.
Food Funct ; 6(10): 3323-33, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26256648

RESUMEN

A novel extraction method, homogenate-assisted negative pressure cavitation extraction (HNPCE), was designed for the extraction and determination of the main phenolic compounds of Pyrola incarnata Fisch. by LC-MS/MS. The particle sizes and extraction yields in the process of homogenization were compared with conventional pulverization. The results showed that homogenization for less than 120 s could produce more suitable particle size powders for analyte extraction. The following NPCE parameters were optimized by a BBD test and under the optimal conditions, the maximum extraction yields of arbutin, epicatechin, hyperin, 2'-O-galloylhyperin and chimaphilin increased by 68.7%, 72.0%, 43.3%, 62.5% and 34.5% with respect to normal NPCE. The LC-MS/MS method was successfully applied for the quantification of five target compounds in pyrola, and the results of the precision test indicated a high accuracy of the present method for the quantification of the target compounds in pyrola. Furthermore, the antioxidant activities of the pyrola extracts were also determined. The results showed that pyrola had good antioxidant activities and it was a valuable antioxidant natural source.


Asunto(s)
Cromatografía Liquida , Fenoles/análisis , Extractos Vegetales/análisis , Pyrola/química , Espectrometría de Masas en Tándem , Antioxidantes/análisis , Arbutina/análisis , Catequina/análisis , Ácido Gálico/análogos & derivados , Ácido Gálico/análisis , Naftoquinonas/análisis , Quercetina/análogos & derivados , Quercetina/análisis , Reproducibilidad de los Resultados
6.
J Sep Sci ; 36(23): 3799-806, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24174124

RESUMEN

A rapid, green and effective miniaturized sample preparation technique, ionic-liquid-assisted microwave distillation coupled with headspace single-drop microextraction was developed for the extraction of essential oil from dried Dryopteris fragrans. 1-Ethyl-3-methylimidazolium acetate was the optimal ionic liquid as the destruction agent of plant cell walls and microwave absorption was medium. n-Heptadecane (2.0 µL) was adopted as the suspended microdrop solvent in the headspace for the extraction and concentration of essential oil. The optimal parameters of the proposed method were an irradiation power of 300 W, sample mass of 0.9 g, mass ratio of ionic liquids to sample of 2.8, extraction temperature of 79°C, and extraction time of 3.6 min. In comparison to the previous reports, the proposed technique could equally monitor all the essential oil components with no significant differences in a simple way, which was more rapid and required a much lower amount of sample.


Asunto(s)
Técnicas de Química Analítica/métodos , Dryopteris/química , Cromatografía de Gases y Espectrometría de Masas , Líquidos Iónicos/química , Microextracción en Fase Líquida , Microondas , Aceites Volátiles/análisis , Destilación , Aceites Volátiles/química
7.
Food Chem ; 141(3): 2213-9, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23870950

RESUMEN

The variation of antioxidant activity and active components in pyrola [Passiflora incarnata Fisch.] from eight sites in Northeast China were investigated. Total phenolic and flavonoid contents were determined and varied within the range of 39.66-181.48 mg/g and 2.47-22.11 mg/g, respectively. Antioxidant activities were determined by scavenging activity against DPPH and ABTS, by a reducing power test and by a ß-carotene-linoleic acid bleaching test. The IC50 of Tahe samples determined by the DPPH test was 0.106±0.006 mg/mL which was very close to that of Vc (0.076±0.004 mg/mL). The Tahe samples had good antioxidant activity. Principal component activity analysis indicated that the Tahe samples of P. incarnata had the highest potential antioxidant properties, and may be a valuable antioxidant natural resource in the northeast of China.


Asunto(s)
Antioxidantes/análisis , Flavonoides/análisis , Passiflora/química , Extractos Vegetales/análisis , China , Geografía , Passiflora/clasificación , Fenoles/análisis
8.
Bioresour Technol ; 136: 766-70, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23566471

RESUMEN

A new biotransformation method of producing resveratrol with co-immobilized edible Aspergillus niger and Yeast (AY) was investigated. The biotransformation conditions were optimized for the resveratrol production under 30 °C, pH 6.5, 2 days, liquid-solid ratio 12:1 (mL/g), the yield of resveratrol reached 33.45 mg/g, which increased 11-fold to that of untreated one. The conversion rate of polydatin reached 96.7%. The residual activity of immobilized microorganism was 83.2% after used for 15 runs. The developed method could be an effectively alternative biotransformation method for producing resveratrol from the plants.


Asunto(s)
Aspergillus niger/metabolismo , Fallopia japonica/metabolismo , Glucósidos/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Saccharomyces cerevisiae/metabolismo , Estilbenos/metabolismo , Biotransformación , Células Inmovilizadas/metabolismo , Fallopia japonica/microbiología , Reciclaje , Resveratrol
9.
Food Chem ; 138(4): 2152-8, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23497870

RESUMEN

In this study, aqueous enzymatic process (AEP) assisted by microwave extraction (ME) of oil from yellow horn (Xanthoceras sorbifolia Bunge.) seed kernel was investigated. Central composite design (CCD) and response surface methodology (RSM) were used to optimise an enzyme cocktail (cellulase, hemicellulase, pectinase) for AEP. The main factors of ME were also studied. A maximal oil extraction yield of 55.8% was achieved under optimal conditions. Moreover, scanning electron microscope (SEM) was applied to characterise the extraction process. Analysing chemical composition of the extracted oil by GC-MS showed that the content of unsaturated fatty acids by this emerging method (91.18%) was similar to that by conventional organic solvent extraction (88.76%). In addition, the main physicochemical properties and antioxidant activities of yellow horn oil were measured to evaluate its quality. The present research supported necessary data for the green extraction method of edible oil in food industry.


Asunto(s)
Fraccionamiento Químico/métodos , Aceites de Plantas/aislamiento & purificación , Sapindaceae/química , Semillas/química , Fraccionamiento Químico/instrumentación , Cromatografía de Gases y Espectrometría de Masas , Glicósido Hidrolasas/química , Microondas , Aceites de Plantas/análisis , Control de Calidad
10.
J Agric Food Chem ; 61(6): 1165-71, 2013 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-23320913

RESUMEN

In this study, the effect of UV irradiation (UV-A, UV-B, and UV-C) on phytochemicals, total phenolics, and antioxidant activity of postharvest pigeon pea leaves was evaluated. The response of pigeon pea leaves to UV irradiation was phytochemical specific. UV-B and UV-C induced higher levels of phytochemicals, total phenolics, and antioxidant activity in pigeon pea leaves compared with UV-A. Furthermore, UV-B irradiation proved to possess a long-lasting effect on the levels of phenolics and antioxidant activity. After adapting for 48 h at 4 °C following 4 h UV-B irradiation, total phenolics and antioxidant activity were approximately 1.5-fold and 2.2-fold increased from 39.4 mg GAE/g DM and 15.0 µmol GAE/g DM to 59.1 mg GAE/g DM and 32.5 µmol GAE/g DM, respectively. These results indicate that UV irradiation of pigeon pea leaves can be beneficial in terms of increasing active components and antioxidant activity.


Asunto(s)
Antioxidantes/análisis , Cajanus/química , Extractos Vegetales/análisis , Cajanus/crecimiento & desarrollo , Cajanus/efectos de la radiación , Fenoles/análisis , Hojas de la Planta/química , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/efectos de la radiación
11.
Food Chem ; 138(1): 173-9, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23265473

RESUMEN

An ionic liquid-based ultrasonic-assisted extraction (ILUAE) method had been used for the effective extraction of isoliquiritigenin (IQ), liquiritin (LQ) and glycyrrhizic acid (GA) from licorice. The ionic liquids with different cations and anions were investigated in this work and 0.5 M 1-butyl-3-methylimidazolium bromide solution was selected as solvent. In addition, the technical parameters including soaking time, solid-liquid ratio, ultrasonic power and time were optimized. Compared with the conventional solvent extraction, the proposed approach exhibited higher efficiency, which indicated the ILUAE was an efficient, rapid and simple sample preparation technique. There was no degradation of the target analytes had been observed at the optimum conditions which was evidenced by the stability studies performed with standard of IQ, LQ and GA. The proposed method also showed high reproducibility and was environmental friendly.


Asunto(s)
Chalconas/aislamiento & purificación , Fraccionamiento Químico/métodos , Flavanonas/aislamiento & purificación , Glucósidos/aislamiento & purificación , Glycyrrhiza/química , Ácido Glicirrínico/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Ultrasonido/métodos , Chalconas/análisis , Cromatografía Líquida de Alta Presión , Flavanonas/análisis , Glucósidos/análisis , Ácido Glicirrínico/análisis , Líquidos Iónicos/química , Extractos Vegetales/análisis
12.
Phytother Res ; 27(10): 1517-23, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23192753

RESUMEN

Corilagin is a member of polyphenolic tannins. Its antimicrobial activity and action mechanism against Escherichia coli, Staphylococcus aureus and Candida albicans were investigated through membrane permeability. Crystal violet staining determination, outer membrane (OM) and inner membrane (IM) permeability, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and atomic force microscopy (AFM) were used as methods for our investigation. The minimum inhibitory concentrations were 62.5, 31.25 and 62.5 µg/mL for E. coli, S. aureus and C. albicans, respectively. Crystal violet results and SDS-PAGE of supernatant proteins showed that corilagin dose-dependently affected membrane permeability of E. coli and C. albicans but not of S. aureus. OM and IM permeability assays revealed comparable results for E. coli. By using AFM, we demonstrated extensive cell surface alterations of corilagin-treated E. coli and C. albicans. SDS-PAGE of precipitated proteins revealed possible targets of corilagin, i.e. Fib, Sae R, Sar S in S. aureus and Tye 7p in C. albicans. In conclusion, corilagin inhibited the growth of E. coli and C. albicans by disrupting their membrane permeability and that of S. aureus by acting on Fib, Sae R and Sar S but not on membrane integrity.


Asunto(s)
Candida albicans/efectos de los fármacos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Glucósidos/farmacología , Staphylococcus aureus/efectos de los fármacos , Candida albicans/citología , Escherichia coli/citología , Violeta de Genciana , Taninos Hidrolizables , Pruebas de Sensibilidad Microbiana , Microscopía de Fuerza Atómica , Staphylococcus aureus/citología , Taninos/farmacología
13.
Bioresour Technol ; 128: 673-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23220401

RESUMEN

In the present study, yellow horn shell residues treated by ionic liquid (IL) were prepared for oil removal from water. Scanning electron microscope (SEM) analysis was applied to represent the effects of IL-treatment on this new cellulosic biosorbent. Furthermore, the comprehensive sorption capacities of the shell residues for five types of oils in pure oil and oily water medium were evaluated. The maximum sorption capacities of IL-treated shell residues (0.39-0.61 g/g) were about 1.5-fold to those of untreated shell residues (0.32-0.42 g/g), respectively. The effects of main environmental factors (temperature and pH) on oil removal were also studied. Kinetic models were successfully established for analyzing the oil sorption process. In addition, it was found that the IL-treated shell residues could be reused for several times. The results indicated that IL-treated yellow horn shell residues could be developed as an ideal biosorbent for oil removal from water.


Asunto(s)
Aceites/aislamiento & purificación , Sapindaceae/química , Semillas/química , Ultrafiltración/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Agua/química , Adsorción , Líquidos Iónicos , Aceites/química , Contaminantes Químicos del Agua/química
14.
J Sep Sci ; 35(24): 3600-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23225724

RESUMEN

An ionic liquid-based surfactant combined with microwave-assisted extraction method, followed by RP-HPLC-diode array detection (DAD) with a core shell column, was successfully applied in extracting and quantifying four major phloroglucinols from Dryopteris fragrans. Eight ionic liquids with different cation and anion were investigated, and 1-octyl-3-methylimidazolium bromide presented the best relative extraction efficiency for four phloroglucinols. The optimum conditions of this method were as follows: ionic liquid concentration 0.75 M, liquid/solid ratio 12:1 mL/g, extraction time 7 min, extraction temperature 50°C, and irradiation power 600 W. The quality analytical parameters of the method were obtained based on the linearity, precision, accuracy, detection, and quantification limits. The recoveries were between 96.90 and 103.5% with standard deviations not higher than 4.7%. Compared with ionic liquid-based heat reflux extraction, ultrasonic-assisted extraction, negative-pressure cavitation extraction, and conventional microwave-assisted extraction, the relative extraction efficiencies of the proposed method for four phloroglucinols increased 1.5-40.4%. The method was successfully applied for the quantification of four major phloroglucinols from D. fragrans. All these results suggest that the developed method represents an excellent alternative for the extraction and quantification of phloroglucinols in other plant materials.


Asunto(s)
Helechos/química , Microondas , Floroglucinol/análisis , Tensoactivos/química , Cromatografía Líquida de Alta Presión , Iones , Espectroscopía de Resonancia Magnética , Floroglucinol/química , Estándares de Referencia , Solventes
15.
J Sep Sci ; 35(21): 2875-83, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23001940

RESUMEN

In this study, an ionic liquid-based microwave-assisted extraction (ILMAE) followed by high-performance liquid chromatography-diode array detector with a pentafluorophenyl column for the extraction and quantification of eight flavonoid glycosides in pigeon pea leaves is described. Compared with conventional extraction methods, ILMAE is a more effective and environment friendly method for the extraction of nature compounds from herbal plants. Nine different types of ionic liquids with different cations and anions were investigated. The results suggested that varying the anion and cation had significant effects on the extraction of flavonoid glycosides, and 1.0 M 1-butyl-3-methylimidazolium bromide ([C4MIM]Br) solution was selected as solvent. In addition, the extraction procedures were also optimized using a series of single-factor experiments. The optimum parameters were obtained as follows: extraction temperature 60°C, liquid-solid ratio 20:1 mL/g and extraction time 13 min. Moreover, an HPLC method using pentafluorophenyl column was established and validated. Good linearity was observed with the regression coefficients (r(2)) more than 0.999. The limit of detection (LODs) (S/N = 3) and limit of quantification (LOQs) (S/N = 10) for the components were less than 0.41 and 1.47 µg/mL, respectively. The inter- and intraday precisions that were used to evaluate the reproducibility and relative standard deviation (RSD) values were less than 4.57%. The recoveries were between 97.26 and 102.69%. The method was successfully used for the analysis of samples of pigeon pea leaves. In conclusion, the developed ILMAE-HPLC-diode array detector using pentafluorophenyl column method can be applied for quality control of pigeon pea leaves and related medicinal products.


Asunto(s)
Cajanus/química , Cromatografía Líquida de Alta Presión/métodos , Flavonoides/análisis , Flavonoides/aislamiento & purificación , Glicósidos/análisis , Extracción Líquido-Líquido/métodos , Extractos Vegetales/análisis , Cromatografía Líquida de Alta Presión/instrumentación , Glicósidos/aislamiento & purificación , Líquidos Iónicos , Microondas , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química
16.
Molecules ; 17(3): 3510-23, 2012 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-22430118

RESUMEN

In present study, the performance and separation characteristics of 21 macroporous resins for the enrichment and purification of deoxyschizandrin and γ-schizandrin, the two major lignans from Schisandra chinensis extracts, were evaluated. According to our results, HPD5000, which adsorbs by the molecular tiers model, was the best macroporous resin, offering higher adsorption and desorption capacities and higher adsorption speed for deoxyschizandrin and γ-schizandrin than other resins. Columns packed with HPD5000 resin were used to perform dynamic adsorption and desorption tests to optimize the technical parameters of the separation process. The results showed that the best adsorption time is 4 h, the rate of adsorption is 0.85 mL/min (4 BV/h) and the rate of desorption is 0.43 mL/min (2 BV/h). After elution with 90% ethanol, the purity of deoxy-schizandrin increased 12.62-fold from 0.37% to 4.67%, the purity of γ-schizandrin increased 15.8-fold from 0.65% to 10.27%, and the recovery rate was more than 80%.


Asunto(s)
Ciclooctanos/aislamiento & purificación , Frutas/química , Lignanos/aislamiento & purificación , Compuestos Policíclicos/aislamiento & purificación , Resinas Sintéticas/química , Schisandra/química , Adsorción , Ciclooctanos/química , Lignanos/química , Compuestos Policíclicos/química
17.
Bioresour Technol ; 108: 112-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22284757

RESUMEN

In this study, biodiesel production from yellow horn (Xanthoceras sorbifolia Bunge.) seed oil using ion exchange resin as heterogeneous catalyst was investigated. After illustration of the mechanisms of transesterification reactions catalyzed by typical ion exchange resins, the factors affecting microwave-assisted transesterification process were studied. A high conversion yield of about 96% was achieved under optimal conditions using high alkaline anion exchange resins as catalyst. Analyzing the FAMEs composition by GC-MS and main physical-chemical properties demonstrated that the biodiesel product prepared from yellow horn seed oil was of high quality. Compared with conventional alkali catalyst, the outstanding characteristics of reusability and operational stability made the resin catalyst more predominant for biodiesel production. In addition, a comprehensive kinetic model was established for analyzing the reaction. The results of present research showed that microwave-assisted transesterification process catalyzed by high alkaline anion exchange resin was a green, effective and economic technology for biodiesel industry.


Asunto(s)
Biocombustibles , Biotecnología/métodos , Resinas de Intercambio Iónico/química , Aceites de Plantas/química , Sapindaceae/química , Semillas/química , Catálisis , Esterificación , Cromatografía de Gases y Espectrometría de Masas , Microondas , Modelos Químicos
18.
J Pharm Biomed Anal ; 61: 199-206, 2012 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-22209481

RESUMEN

A simple, efficient and environment-friendly chromatographic separation method was developed for preparative separation and enrichment of dryofragin and aspidin BB from Dryopteris fragrans. The adsorption properties of twelve macroporous adsorption resins were evaluated. The three selected resins were further screened depending on the separation performance of their packed columns, in which AB-8 resin showed better separation efficiency for dryofragin and aspidin BB. In order to maximize column efficiency, the operating parameters (flow rate, ethanol concentration and volume) of the resin column chromatography were optimized and compared with the conventional resin column adsorption. After preparative separation and enrichment on resin column chromatography, the contents of dryofragin and aspidin BB in the product were 8.39- and 5.99-fold increased with recovery yields of 91.22% and 75.64%, respectively. Moreover, the regenerated adsorbent exhibited excellent reusability within at least five cycles of adsorption/desorption. It suggested that multi-targets would be enriched effectively by resin column chromatography.


Asunto(s)
Química Farmacéutica/métodos , Dryopteris/química , Floroglucinol/análogos & derivados , Extractos Vegetales/química , Resinas Sintéticas/química , Adsorción , Química Farmacéutica/normas , Cromatografía Liquida/métodos , Cromatografía Liquida/normas , Floroglucinol/química
19.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(30): 3444-51, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-21963273

RESUMEN

In this study, ester-bond biphenyl cyclooctene lignans were efficiently hydrolytically degraded into free biphenyl cyclooctene lignans by ion exchange resin transformation and simultaneous removal of impurities by macroporous resin. The OH-type strongly basic anion exchange resin 201×7 was the best one, and the dynamic hydrolysis efficiency was 146.7±5.0%. HPD5000 macroporous resin, which offered higher adsorption and desorption capacities and faster adsorption than other resins. The purity of free biphenyl cyclooctene lignans in the product increased from 5.14±0.24% to 79.67±0.0.67%. After dynamic catalytic transformation by 201×7 resin combined with purification of HPD5000 resin, the yield and the purity of free biphenyl cyclooctene lignans in the product were 132.1±4.7% and 80.91±3.53%, respectively.


Asunto(s)
Cromatografía por Intercambio Iónico/métodos , Ciclooctanos/aislamiento & purificación , Dioxoles/aislamiento & purificación , Lignanos/aislamiento & purificación , Compuestos Policíclicos/aislamiento & purificación , Schisandra/química , Adsorción , Análisis de Varianza , Etanol , Frutas/química , Hidrólisis , Resinas de Intercambio Iónico , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray , Temperatura
20.
Environ Toxicol Pharmacol ; 32(1): 63-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21787731

RESUMEN

The composition of the essential oil of Rosemary was analyzed by gas chromatography-mass spectrometry (GC-MS). 22 components, which constitute 97.41% of the oil, were identified. The major constituents were 1,8-Cineole (26.54%) and α-Pinene (20.14%). Minimum inhibitory concentrations (MICs), minimal bactericidal concentration (MBC) and time-kill dynamic processes against three Gram-positive bacteria (Staphylococcus epidermidis, Staphylococcus aureus and Bacillus subtilis), three Gram-negative bacteria (Proteus vulgaris, Pseudomonas aeruginosa and Escherichia coli) and two fungi (Candida albicans and Aspergillus niger) were determined for the oil, 1,8-Cineole and α-Pinene. The oil showed pronounced antibacterial and antifungal activity than 1,8-Cineole and α-Pinene against all of the tested microbes. Furthermore, the survival rates and morphological changes of S. aureus after treatment with different concentrations of the essential oil were assessed by flow cytometry (FCM) and atomic force microscopy (AFM).


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Aspergillus niger/efectos de los fármacos , Candida albicans/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Aceites Volátiles/farmacología , Aspergillus niger/crecimiento & desarrollo , Monoterpenos Bicíclicos , Candida albicans/crecimiento & desarrollo , Ciclohexanoles/análisis , Ciclohexanoles/farmacología , Eucaliptol , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Monoterpenos/análisis , Monoterpenos/farmacología , Aceites Volátiles/química , Rosmarinus/química
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