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1.
Anal Bioanal Chem ; 411(30): 8091-8101, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31773227

RESUMO

Sensitive and robust in situ chemical analysis of organic biomarkers is essential in the endeavor of finding chemical signatures of life either extinct or extant on our solar system bodies such as Europa, Enceladus, or Titan. Development of new analytical instruments and accompanying methodologies are needed, especially those that are compatible with unknown and diverse samples potentially found on solar system targets and that avoid complexities involved with other wet chemistry techniques (desalting, derivatization and contamination issues, etc.). In this study, we demonstrate that online supercritical fluid extraction and supercritical fluid chromatography with water-saturated CO2 can extract and separate nonpolar analytes of astrobiological interest, such as free fatty acids, polycyclic aromatic hydrocarbons, and polycyclic aromatic compounds containing nitrogen or sulfur. Silica was used as a support material to immobilize aqueous samples during extraction. A C18 stationary phase with an embedded polar functional group and efficient end-capping in combination with water in the mobile phase allowed efficient separation of both free fatty acids and basic compounds. The total analysis time was 30 min, including extraction, equilibration, and separation. Detection was performed with a UV detector and a quadrupole mass spectrometer equipped with electrospray ionization. The method was validated in terms of lower detection limits (0.02-40 µg/L), precision (repeatability 3-13%), relative standard deviation (RSD), intermediate precision 4-26% (RSD), trueness (bias ranging from - 48 to 9%), and retention time shifts (< 2% RSD) for 16 analytes in sample matrices with sodium chloride and magnesium sulfate that may be present in ocean worlds such as Europa or Enceladus. Graphical Abstract.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Planetas , Biomarcadores/metabolismo , Humanos
2.
Artigo em Inglês | MEDLINE | ID: mdl-31706150

RESUMO

The study is aimed to develop a rapid and efficient supercritical fluid chromatography coupled with diode-array detection (SFC-DAD) method for simultaneous quantification of six flavonoids in Citri Reticulatae Pericarpium (CRP). The chromatographic parameters including stationary phase, mobile phase composition, back pressure, temperature and flow rate, were systematically optimized with single-factor test. The results indicated that the six compounds were baseline separated on an Agilent Zorbax RX-SIL column using gradient elution within 10 min. The optimized mobile phase was constituted of carbon dioxide (CO2) and methanol. And the parameters were set as follows: backpressure, 95 bar; temperature, 45 °C; flow rate, 0.8 mL/min. The optimized method showed satisfactory retention and resolution for the analytes. The method was validated to demonstrate its selectivity, linearity, precision, accuracy and robustness. Thus, the verified SFC method was successfully applied to quantification of flavonoids present in CRP samples. The results indicated that SFC has the potential to become an excellent alternative for the analysis of flavonoids in herbal medicines, owning to its intrinsic features like high efficiency, separation speed and eco-friendly characteristics.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Citrus/química , Flavonoides/análise , Frutas/química , Extratos Vegetais/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
3.
J Mass Spectrom ; 54(10): 791-801, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31652381

RESUMO

Supercritical fluid chromatography (SFC) has experienced a particular revival in recent years thanks to the development of robust and efficient commercial systems. Because of its physico-chemical properties, supercritical carbon dioxide (CO2 ) mixed with cosolvents and additives is particularly suitable for SFC to allow the elution of compounds of different polarities and more particularly complex lipids. Hyphenation with mass spectrometry (MS) is increasingly described in the literature but still requires many further developments in order to be as user-friendly as coupling with liquid chromatography. The basic concepts of SFC and MS hyphenation will be first considered. Then a representative example of method development in lipidomics will be introduced. In conclusion, the challenges and future needs in this field of research will be discussed.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Lipídeos/análise , Espectrometria de Massas em Tandem/métodos , Acetatos/química , Técnicas Biossensoriais , Dióxido de Carbono/química , Limite de Detecção , Reprodutibilidade dos Testes , Solventes/química
4.
Chem Biodivers ; 16(12): e1900401, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31654480

RESUMO

The complement system participates in host defense by eliminating microorganisms and triggering inflammation. However, insufficient control or exacerbated complement activation contributes to inflammatory diseases. Since promising antioxidant and anti-inflammatory activities have been identified in Arctium lappa L. extracts, this study aims to explore the effect of A. lappa extracts on the lectin pathway (LP) of complement activation. Four extracts were obtained by supercritical extraction using scCO2 with or without ethanol as co-solvent, at different temperatures and pressures (E1: 2.2 mg/mL, E2: 2.6 mg/mL and E3: 2.0 mg/mL, E4: 1.5 mg/mL). To evaluate the effect of A. lappa extracts on the LP activation, an ELISA assay using mannose binding lectin pathway of complement was carried out with C4 detection. All extracts showed a concentration-dependent inhibitory effect on the activation of complement by the LP. The following IC50 were observed for E1, E2, E3 and E4: 179.4 µg/mL, 74.69 µg/mL, 119.1 µg/mL and 72.19 µg/mL, respectively. Our results suggest that A. lappa extracts are potential candidates for the treatment of inflammatory disorders that are complement-related.


Assuntos
Arctium/química , Cromatografia com Fluido Supercrítico/métodos , Proteínas do Sistema Complemento/metabolismo , Lectinas/metabolismo , Extratos Vegetais/química , Arctium/metabolismo , Dióxido de Carbono/química , Proteínas do Sistema Complemento/agonistas , Lectinas/antagonistas & inibidores , Folhas de Planta/química , Folhas de Planta/metabolismo , Temperatura Ambiente
5.
BMC Complement Altern Med ; 19(1): 270, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623582

RESUMO

BACKGROUND: Benign prostatic hyperplasia (BPH) is a pathological condition affecting older men. BPH complications often lead to deterioration in the quality of life. Serenoa repens (Saw Palmetto) is used for treating lower urinary tract infections in traditional medicine. METHODS: This study was performed to compare the efficacy of ß-sitosterol enriched saw palmetto oil (VISPO) and conventional saw palmetto oil (SPO) extracted using supercritical fluid extraction, in alleviating the BPH complications using testosterone-induced BPH model rats. The animals received testosterone (5 mg/kg s.c.) with or without SPO and VISPO (200 and 400 mg/kg b.w.) or Finasteride (1 mg/kg b.w.) p.o. for 28 days. At the end of the experiment, overnight fasted animals were euthanized, blood samples collected for serum analysis of testosterone. Prostate tissue histomorphology was examined by hematoxylin and eosin (H&E) staining. Western blot analysis was performed using prostate tissue homogenates. RESULTS: VISPO exhibited superior efficacy compared to SPO as evident from the significant decrease in prostate weight to body weight ratio, serum testosterone level and increase in growth inhibition of prostate tissue compared to BPH group (p < 0.001). Histological examination of prostate tissue samples showed that VISPO treatment was comparatively better than SPO in improving the hyperplastic patterns. Further, VISPO significantly regulated the expression of inflammatory and apoptotic marker proteins in BPH rats. CONCLUSION: Our data provide experimental evidence that ß-sitosterol enriched saw palmetto oil could be higher efficacious in treating the BPH complications compared to the conventional saw palmetto oil preparations.


Assuntos
Fitosteróis/administração & dosagem , Extratos Vegetais/administração & dosagem , Hiperplasia Prostática/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína X Associada a bcl-2/genética , Animais , Cromatografia com Fluido Supercrítico , Humanos , Masculino , Fitosteróis/isolamento & purificação , Fitoterapia , Extratos Vegetais/isolamento & purificação , Próstata/efeitos dos fármacos , Próstata/imunologia , Hiperplasia Prostática/sangue , Hiperplasia Prostática/induzido quimicamente , Hiperplasia Prostática/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Ratos , Ratos Wistar , Serenoa/química , Sitosteroides/administração & dosagem , Sitosteroides/isolamento & purificação , Testosterona/efeitos adversos , Testosterona/sangue , Proteína X Associada a bcl-2/imunologia
6.
J Dairy Sci ; 102(12): 10855-10866, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31548058

RESUMO

In recent years, using dairy phospholipids (PL) as functional ingredients has increased because PL have nutritional benefits and functional properties. In this study, a novel 2-step supercritical fluid extraction (SFE) process was used to extract whey protein phospholipid concentrate (WPPC), a dairy co-product obtained during the manufacture of whey protein isolate, for PL enrichment. In the first step, nonpolar lipids in WPPC were removed using neat supercritical carbon dioxide (S-CO2) at 41.4 MPa and 60°C. In the second stage, the feasibility of using the polar solvent ethanol as a co-solvent to increase the solubility of S-CO2 extraction solvent was explored. A 3 × 3 × 2 factorial design with extraction pressure (35.0, 41.4, and 55.0 MPa), temperature (40 and 60°C), and concentration of ethanol (10, 15, and 20%) as independent factors was used to evaluate the extraction efficiency providing the most total PL, and the best proportion of each individual PL from the spent solids collected during S-CO2 SFE. All lipid fractions were analyzed using thin-layer chromatography and high-performance lipid chromatography. The total amount of PL extracted from WPPC was significantly affected by ethanol concentration; the extraction pressure and temperature were nonsignificant. The optimal SFE condition for generating a concentrated PL lipid fraction was 35.0 MPa, 40°C, and 15% ethanol concentration; the highest amount of extracted PL averaged 26.26 g/100 g of fat. Moreover, adjusting SFE condition allowed successful recovery of a high concentration of sphingomyelin, phosphatidylcholine, and phosphatidylethanolamine, giving averages of 11.07, 10.07, and 7.2 g/100 g of fat, respectively, 2 to 3 times more than conventional solvent extraction. In addition, exhausted solids obtained after the SFE process were enriched with denatured proteins (72% on dry basis) with significantly more water-holding capacity and emulsifying capacity than untreated WPPC. Overall, this 2-stage SFE process using neat S-CO2 and ethanol has the greatest potential to produce a PL-rich lipid fraction from WPPC.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Fosfolipídeos/isolamento & purificação , Proteínas do Soro do Leite/química , Dióxido de Carbono/química , Cromatografia em Camada Delgada , Etanol/química , Fosfolipídeos/química , Solubilidade , Solventes/química , Temperatura Ambiente
7.
J Chromatogr A ; 1604: 460494, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31488292

RESUMO

The objective of this study is to understand the behavior of a peptide in a medium containing supercritical carbon dioxide mixed with an alcohol (methanol) and acidic or basic additives in uncommonly high concentrations. Chirobiotic TAG is a chromatographic column made of silica bonded with a macrocyclic peptide, teicoplanin aglycone. With this stationary phase, two additives (trifluoroacetic acid and isopropylamine) were tested under extreme concentration conditions to observe the behavior of this peptide. Indeed, concentrations exceeding 1 M in the methanol co-solvent (>0.1 M overall concentration in the CO2-methanol mixture) were used whereas usual additive concentrations employed in supercritical fluid chromatography (SFC) rarely exceed 50 mM in the co-solvent. One purpose was to modify the apparent pH of the fluid, which is normally slightly acidic (around 5) and consequently possibly changing the ionization state of the peptide. Firstly, the effect of acidic and basic additives on the polarity and the apparent pH were evaluated with the help of color indicators. This served to assess the ionization state of the peptide under the selected operating conditions. Secondly, 54 achiral and 24 chiral molecules were injected in the chromatographic column at different levels of additives. The achiral species served at establishing retention models based on linear solvation energy relationships (LSER), while the chiral species were examined for their enantioresolution. From the LSER equations and observation of chromatograms, it appeared that specific interactions between the peptide-based stationary phase and the analytes evolved when increasing the concentration of additives, particularly hydrogen bonds and ionic interactions. A bare silica stationary phase (Acquity BEH) served as reference to deconvolute the contributions of silica support and bonded peptide. This study, with these extreme conditions of mobile phase, could be useful to understand the behavior of such peptides in SFC mobile phases and also improve the knowledge of the effects of additives in SFC, which should be helpful in the future prospect of analyzing large biomolecules in SFC.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Teicoplanina/análogos & derivados , Compostos Azabicíclicos/química , Ligações de Hidrogênio , Concentração de Íons de Hidrogênio , Íons , Metanol/química , Piperazinas/química , Solventes/química , Estereoisomerismo , Teicoplanina/química , Teicoplanina/isolamento & purificação , Ácido Trifluoracético/química
8.
J Chromatogr A ; 1604: 460485, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31477276

RESUMO

Macrocyclic glycopeptides have been used as chromatographic stationary phases for over twenty years, particularly for their ability to separate enantiomers. While they are mostly used with buffered aqueous liquid mobile phases, they can also be used in supercritical fluid chromatography (SFC) with mobile phases comprising pressurized carbon dioxide and a co-solvent (like methanol), possibly comprising acidic or basic additives. In the present study, we compared three macrocyclic glycopeptide stationary phases (Chirobiotic V2, Chirobiotic T and Chirobiotic TAG) in SFC with carbon dioxide - methanol (90:10) containing no additives. First, the interactions contributing to retention are evaluated with a modified version of the solvation parameter model, comprising five Abraham descriptors (E, S, A, B, V) and two additional descriptors to take account of interactions with ionizable species (D- and D+). Linear solvation energy relationships (LSER) are established based on the retention of 145 achiral analytes. Secondly, the contributions of interactions to enantioseparations are discussed, based on the analysis of 67 racemates. The individual success rate on each phase was observed to be moderate, especially as these phases are known to be more efficient when acidic or basic additives are employed. Chirobiotic TAG proved more successful than the other two phases. Discriminant analyses were computed to gain some insight on retention mechanisms, but only Chirobiotic TAG provided interpretable results. Finally, the effects of a small proportion of acidic or basic additive on enantioseparation with Chirobiotic T stationary phase are briefly discussed.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Glicopeptídeos/química , Compostos Macrocíclicos/química , Análise Discriminante , Concentração de Íons de Hidrogênio , Solventes , Estereoisomerismo
9.
J Chromatogr A ; 1606: 460386, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31400842

RESUMO

Dihydromyricetin, extracted from Ampelopsis grossedentata, has been widely used as one of Chinese health products in recent years. However, limited chiral separation method hinders the studies of pharmacological and pharmacokinetic activity differences of (+)-dihydromyricetin, (-)-dihydromyricetin, and (±)-dihydromyricetin. Herein, we developed a supercritical fluid chromatography approach for chiral separation of dihydromyricetin. Firstly, effects of chiral stationary phase, co-solvent, and flow rate of mobile phase have been investigated in detail. The resolution of 5.11 was achieved for dihydromyricetin enantiomers on amylose tris(3, 5-dimethylphenylcarbamate)-coated chiral stationary phase with the CO2-methanol mixture (60:40, v/v). With respect to the enantiomeric purity, production rate and solvent consumption of 15 stacked injections, sample loading for semi-preparative separation of dihydromyricetin was optimized in three given equivalents set by volume overloading. Along with increase of sample loading per injection from 40 mg to 120 mg, the productivity of dihydromyricetin increased from 0.07 g (racemate)/g (chiral stationary phase) /24 h to 0.27 g (racemate) /g (chiral stationary phase)/24 h, and the consumption of methanol significantly reduced from 5.86 L/g (racemate) to 1.76 L/g (racemate). Moreover, (-)-dihydromyricetin exhibited better anti-inflammatory activity in TLR 2-related Raw 264.7 cells than (+)-dihydromyricetin and (±)-dihydromyricetin.


Assuntos
Anti-Inflamatórios/farmacologia , Cromatografia com Fluido Supercrítico/métodos , Flavonóis/análise , Flavonóis/química , Animais , Flavonóis/farmacologia , Concentração Inibidora 50 , Camundongos , Células RAW 264.7 , Reologia , Solventes , Estereoisomerismo
10.
Waste Manag ; 97: 131-139, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31447020

RESUMO

Polyethylene (PE) and polypropylene (PP) feedstock contain various additives, such as fillers and colorants, which either degrade or carry through the depolymerization process; thereby causing intense dark colors and a pungent petroleum odor. The combination of color and odor imposes several challenges, limiting the potential markets of the wax products. This study put emphasis on the development of an innovative and environmentally sustainable process based on supercritical fluid extraction (SCFE) to remove organic and inorganic contaminants that cause color and odor in waxes derived from recycled polymers. In terms of organic impurity removal, for PE 81% and for PP 97% removal efficiency was achieved. The color of PE and PP in terms of lightness under CIELAB (lightness, green-red, blue-yellow) color space was improved by 13 and 40 units, respectively. The purified waxes could be utilized in a variety of market segments, including color masterbatch, roofing shingles, rubber, and coatings. Compared with traditional purification technologies based on solvent extraction and absorbent filters, SCFE process offers exceptional advantages, including fast reaction rates, little liquid waste, ease of separation of solutes, and fewer separation stages. This novel process enables producing high-value water white waxes from reclaimed polymeric feedstock with a focus on clean technologies and enhanced resource efficiency.


Assuntos
Cromatografia com Fluido Supercrítico , Plásticos , Polietileno , Polipropilenos , Ceras
11.
J Agric Food Chem ; 67(36): 10256-10264, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31433628

RESUMO

In this study, a simple and effective chiral analytical method was developed to monitor prothioconazole and prothioconazole-desthio at the enantiomeric level using supercritical fluid chromatography-tandem triple quadrupole mass spectrometry. The baseline enantioseparation for prothioconazole and prothioconazole-desthio was achieved within 2 min on a Chiralcel OD-3 column with CO2/0.2% acetic acid-5 mmol/L ammonium acetate 2-propanol (85:15, v/v) as the mobile phase at a flow rate of 1.5 mL/min and column temperature of 25 °C. The limit of quantitation for each enantiomer was 5 µg/kg, with a baseline resolution of >3.0. The results of enantioselective dissipation showed that R-(-)-prothioconazole was preferentially degraded in tomato, cucumber, and pepper under greenhouse conditions. S-(-)-prothioconazole-desthio was preferentially degraded in tomato and cucumber; however, R-(+)-prothioconazole-desthio was preferentially degraded in pepper. Results of this study may help to facilitate more accurate risk assessment of prothioconazole and its major metabolite in agricultural products.


Assuntos
Cucumis sativus/química , Fungicidas Industriais/química , Lycopersicon esculentum/química , Triazóis/química , Triazóis/metabolismo , Cromatografia com Fluido Supercrítico , Cucumis sativus/metabolismo , Lycopersicon esculentum/metabolismo , Piper nigrum/química , Piper nigrum/metabolismo , Estereoisomerismo , Espectrometria de Massas em Tandem , Verduras/química , Verduras/metabolismo
12.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438606

RESUMO

Perezone, a sesquiterpene quinone, is a very important molecule due to its pharmacological activities in addition to the fact that it is considered to be the first secondary metabolite isolated in the new world (America-Mexico, 1852). This study aims to offer a green comparative study about the extraction of the target molecule from the roots of the vegetable specimen Acourtia platyphilla (A. Grey). The study was performed comparing five different modes of extraction: supercritical CO2, electromagnetic infrared and microwave irradiations, mechanical-wave ultrasound versus typical mantle heating procedure. An exhaustive comparative-discussion of the obtained results is provided. It is worth noting that the corresponding quantifications were established using 1H NMR, correlating appropriately the integrals of the vinylic proton H-6 of perezone with the aromatic singlet of p-dinitrobenzene employed as an internal reference. It is also important to highlight that the four presented procedures are novel modes to extract perezone. Finally, a complementary study about the solubility of the target sesquiterpene quinone related to the use of supercritical CO2 is also reported.


Assuntos
Asteraceae/química , Dióxido de Carbono/química , Extratos Vegetais/química , Raízes de Plantas/química , Sesquiterpenos/química , Cromatografia com Fluido Supercrítico
13.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1126-1127: 121740, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31400581

RESUMO

A fast analytical method through supercritical fluid chromatography was developed for enantioselective determination of triadimefon in soil and apple samples. Effects of chiral stationary phases, co-solvents, column temperature, and back pressure on chiral separation of triadimefon were discussed in detail. Chiral stationary phases containing electron-donating units located at phenylcarbamate moieties showed better enanitonrecognition abilities in triadimefon than those with electron-withdrawing units. Then, the modified pretreatment procedure was applied in enantioselective analysis of triadimefon in two matrices. When using cellulose tris(3,5-dimethylphenylcarbamate)-coated silica gel as the chiral stationary phase and the CO2-methanol (95/5, v/v) mixture as the mobile phase, the LOD and LOQ were 0.38 mg/kg and 2.00 mg/kg, respectively, much lower than the others chiral stationary phases. Good linearity (R2 = 0.9999) and recoveries (92.90-105.56%,RSD ≤ 1.52%) for them were achieved.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Resíduos de Praguicidas/análise , Triazóis/análise , Limite de Detecção , Modelos Lineares , Malus/química , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Reprodutibilidade dos Testes , Solo/química , Estereoisomerismo , Triazóis/química , Triazóis/isolamento & purificação
14.
Molecules ; 24(15)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366123

RESUMO

Colchicine was extracted from Gloriosa superba seeds using the Super Critical Fluid (CO2) Extraction (SCFE) technology. The seeds were purified upto 99.82% using column chromatography. Colchicine affinity was further investigated for anticancer activity in six human cancer cell lines, i.e., A549, MCF-7, MDA-MB231, PANC-1, HCT116, and SiHa. Purified colchicine showed the least cell cytotoxicity and antiproliferation and caused no G2/M arrest at clinically acceptable concentrations. Mitotic arrest was observed in only A549 and MDA-MB231 cell lines at 60nM concentration. Our finding indicated the possible use of colchicine at a clinically acceptable dose and provided insight into the science behind microtubule destabilization. However, more studies need to be conducted beforethese findings could be established.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cromatografia com Fluido Supercrítico/métodos , Colchicaceae/química , Colchicina/farmacologia , Sementes/química , Moduladores de Tubulina/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Dióxido de Carbono/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Colchicina/isolamento & purificação , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Extratos Vegetais/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Moduladores de Tubulina/isolamento & purificação
15.
Int J Mol Sci ; 20(15)2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31387229

RESUMO

Inflammatory bowel disease (IBD) is a worldwide healthcare problem calling for the development of new therapeutic drugs. Angelica sinensis and Zingiber officinale Roscoe are two common dietetic Chinese herbs, which are traditionally used for complementary treatment of gastrointestinal disorders. As bioactive constituents, volatile and pungent substances of these two herbs could be effectively extracted together by supercritical fluid extraction. In this study, the supercritical fluid extract of Angelica sinensis and Zingiber officinale Roscoe (AZ-SFE) was obtained by an optimized extraction process and it was chemically characterized. The anti-inflammatory effect and underlying mechanism of AZ-SFE were evaluated in a lipopolysaccharide (LPS)-induced RAW264.7 cell model and a 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)-induced colitis rat model. AZ-SFE notably inhibited the production of NO in LPS-stimulated macrophages, and it inhibited the proliferation of Concanavalin A (Con A)-induced splenocytes with suppression of the Th1 immune response. In vivo, the study demonstrated that AZ-SFE significantly alleviated disease activity, colonic shortening, macroscopic damage and histological injury of TNBS-treated rats with reduction of oxidative stress, suppression of inflammatory cytokines, and modulation of hepcidin and serum iron. These findings suggested that AZ-SFE may be a promising supplement for current IBD therapy.


Assuntos
Angelica sinensis/química , Anti-Inflamatórios não Esteroides/farmacologia , Colite/tratamento farmacológico , Gengibre/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Biomarcadores , Biópsia , Sobrevivência Celular/efeitos dos fármacos , Cromatografia com Fluido Supercrítico , Colite/etiologia , Colite/metabolismo , Citocinas/biossíntese , Modelos Animais de Doenças , Cromatografia Gasosa-Espectrometria de Massas , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/imunologia , Linfócitos/imunologia , Linfócitos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Células RAW 264.7 , Ratos , Baço/imunologia , Baço/metabolismo , Ácido Trinitrobenzenossulfônico/efeitos adversos
16.
J Chromatogr A ; 1606: 460385, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31351592

RESUMO

Isoflavones are phenolic phytoestrogens due to their structural similarity to estradiol, so they usually serve as active component for quality control of traditional Chinese medicines (TCMs) rich in isoflavones. However, TCMs contains various kinds of similar isoflavones, especially isomers, which to a significant extent hinders accurate analysis of isoflavones in TCMs. Here, we present a novel analytical strategy for quality control of TCMs rich in isoflavones using ultra-high performance supercritical fluid chromatography coupled to photodiode array detection (UHPSFC-PDA) and tandem mass spectrometry (UHPSFC-MS/MS). Both chromatography and mass spectrometry parameters were optimized in order to develop an accurate, rapid, sensitive method for quantification of isoflavones. The reproducibility of quantitative analysis of multi-components by single marker (QAMS) using UHPSFC-PDA was discussed in terms of mobile phase gradient, temperature and backpressure for the first time. An analytical method for the analysis of isoflavones using UHPSFC-MS/MS was developed for the first time, and the established method was successfully applied to quantify isoflavones in three species of Radix Puerariae. The study showed Radix Pueraria Peduncularis contained higher amounts of isoflavones than Radix Puerariae Thomsonii, and it is worth noting that Radix Pueraria Peduncularis was often overlooked by researchers. It took less than 8 min with the current method and the limit of detection was not more than 0.05 ng/ml, which was definitely sufficient for anlysis of various samples from TCMs without enrichment.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Isoflavonas/análise , Medicina Tradicional Chinesa , Pueraria/química , Isoflavonas/química , Isomerismo , Modelos Lineares , Pressão , Análise de Componente Principal , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Temperatura Ambiente
17.
J Chromatogr A ; 1605: 360345, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31326091

RESUMO

The use of pesticides has increased sharply in the last decades, not only in agriculture, but also in industry, public health, and other areas. Pyrethroids and organophosphorus insecticides are among the most employed pesticides. These chemicals usually contain asymmetric chiral atoms; thus, they are characterized by stereoisomerism. Although most of these chiral pesticides are produced, used, and released as racemic mixtures, the different enantiomers of these compounds can present different insecticidal activity, different toxicity against vertebrates and invertebrates, and also different persistence in the environment. In fact, in some cases, only one enantiomer is active, while the other can be less active or even toxic to non-target organisms. Therefore, the development of enantioselective analytical methodologies enabling their determination presents a high interest. Different separation techniques, including high performance liquid chromatography, gas chromatography, supercritical fluid chromatography, and capillary electrophoresis, have been employed to achieve the chiral analysis of pyrethroids and organophosphorus insecticides. This review presents the characteristics of the stereoselective analytical methodologies developed with this aim from 2010 to April 2019 and their applications to the analysis of real samples as well as for toxicity and biodegradation studies.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico , Eletroforese Capilar , Inseticidas/análise , Praguicidas/análise , Piretrinas/análise , Estereoisomerismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-31323559

RESUMO

The present study was conducted to check the comparative qualities of essential oils prepared by hydrodistillation (HD) and supercritical fluid techniques. It constitutes the first attempt to investigate the chemical composition of Daucus carota subsp. maritimus extracts using supercritical fluid technology (SFE) as an environmentally clean innovative method of extraction. The effect of pressure on the nature of extractable substances from wild carrot has been performed at a constant temperature of 50 °C and two different pressures (100 and 300 bar). The experimental results showed that pressure had a significant enhancing effect on the fluid transport properties and therefore on yield values. The extraction yield increases from 1.167 to 2.986% while increasing pressure. The chemical compositions of the essential oils prepared by HD and SFE were analyzed on the basis of gas chromatography-mass spectroscopy (GC-MS). Thus, we noticed that all analyzed samples were enriched in geranyl acetate and ß­bisabolene, and that the quantities of different identified substances were extremely sensitive to the extraction method and to the pressure variation in case of SFE.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Daucus carota/química , Óleos Voláteis/isolamento & purificação , Óleos Vegetais/isolamento & purificação , Acetatos/análise , Acetatos/isolamento & purificação , /isolamento & purificação , /isolamento & purificação , Óleos Voláteis/análise , Óleos Vegetais/análise , Pressão
19.
Analyst ; 144(18): 5324-5352, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31348475

RESUMO

Medicinal plants with complex matrices are endowed with a wide scope of biological activities. The separation, quantification, characterization and purification of bioactive components from herbal medicine extracts have always challenged analysts. Fortunately, the advancement of various emerging techniques has provided potent support for improving the method selectivity, sensitivity and run speeds in medicinal plant analyses. In recent years, the advent of new-generation supercritical fluid chromatography (SFC) instruments and a wide diversity of column chemistries, coupled with the intrinsic technical features of SFC, have made it an alternative and prominent analytical platform in the medicinal plant research area. This work aims to give a comprehensive overview of the fundamentals, technical advancement and investigating parameters of SFC in combination with three prevalent detectors. Moreover, the latest research progress of SFC applications in medicinal plant analyses is illuminated, with focus on herbal medicine-related SFC papers on the analytical and preparative scale that were published during the period of 2012 to December 2018. The most relevant applications were classified based on the constituents to be analysed. As for the respective research cases, analytical protocols and data processing strategies were provided, along with the indicated restrictions or superiority of the method; thus, the current status of SFC in medicinal plant analysis was presented.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Compostos Fitoquímicos/análise , Plantas Medicinais/química , Cromatografia com Fluido Supercrítico/instrumentação
20.
Molecules ; 24(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315224

RESUMO

In recent years, great attention has been focused on rapid, selective, and environmentally friendly extraction methods to recover pigments and antioxidants from microalgae. Among these, supercritical fluid extraction (SFE) represents one of the most important alternatives to traditional extraction methods carried out with the use of organic solvents. In this study, the influence of parameters such as pressure, temperature, and the addition of a polar co-solvent in the SFE yields of carotenoids and fat-soluble vitamins from T. obliquus biomass were evaluated. The highest extraction of alpha-tocopherol, gamma-tocopherol, and retinol was achieved at a pressure of 30 MPa and a temperature of 40 °C. It was observed that overall, the extraction yield increased considerably when a preliminary step of sample pre-treatment, based on a matrix solid phase dispersion, was applied using diatomaceous earth as a dispersing agent. The use of ethanol as a co-solvent, under certain conditions of pressure and temperature, resulted in selectively increasing the yields of only some compounds. In particular, a remarkable selectivity was observed if the extraction was carried out in the presence of ethanol at 10 MPa and 40 °C: under these conditions, it was possible to isolate menaquinone-7, a homologous of vitamin K2, which, otherwise, cannot not recovered by using traditional extraction procedures.


Assuntos
Carotenoides/isolamento & purificação , Microalgas/química , Vitaminas/isolamento & purificação , Cromatografia com Fluido Supercrítico , Temperatura Ambiente , Vitamina A/isolamento & purificação , alfa-Tocoferol/isolamento & purificação , gama-Tocoferol/isolamento & purificação
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