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1.
Plant Direct ; 7(6): e504, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37360842

RESUMO

In the natural ecosystem, plants usually grow at high vegetation density for yield maximization. The high-density planting triggers a variety of strategies to avoid canopy shade and competes with their neighbors for light and nutrition, which are collected termed shade avoidance responses. The molecular mechanism underlying shade avoidance and nutrition has expanded largely in the past decade; however, how these two responses intersect remains poorly understood. Here, we show that simulated shade undermined Pi starvation response and the phytohormone JA is involved in this process. We found that the JA signaling repressor JAZ proteins directly interact with PHR1 to repress its transcriptional activity on downstream targets, including phosphate starvation induced genes. Furthermore, FHY3 and FAR1, the negative regulators of shade avoidance, directly bind to promoters of NIGT1.1 and NIGT1.2 to activate their expression, and this process is also antagonized by JAZ proteins. All these results finally result in attenuation of Pi starvation response under shade and Pi-depleted conditions. Our findings unveil a previously unrecognized molecular framework whereby plants integrate light and hormone signaling to modulate phosphate responses under plant competition.

2.
EBioMedicine ; 85: 104285, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36182776

RESUMO

BACKGROUND: Crohn's disease (CD) is a chronic inflammatory disorder characterized by intestinal immune dysfunction. Multiple factors, including gut dysbiosis, are involved in the pathogenesis of CD. However, the effect of commensal bacteria on controlling the inflammatory response in individuals with CD remains unclear. METHODS: We detected Toll-like receptor 2 (TLR2), TLR4, and TLR5 expression in Roseburia intestinalis (R. intestinalis)-treated mice with 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. Then, we quantified the signs of colonic inflammation, the proportion of regulatory T cells (Tregs) and the expression of thymic stromal lymphopoietin (TSLP) and transforming growth factor (TGF)-ß in TLR-5-deficient (Tlr5-/-) mice, bone marrow chimera mice (generated using wild-type (WT) and Tlr5-/- mice), and anti-TSLP/anti-TGFß-treated C57BL/6 mice with colitis induced by TNBS. In vitro, we used the lipopolysaccharide (LPS)-stimulated human intestinal epithelial cell line Caco-2 as an inflammatory colon cell model treated with or without the TLR5-siRNA intervention in the presence of R. intestinalis and incubated human monocyte-derived dendritic cells (DCs) with the supernatant of Caco-2 cells. Then, we cocultured human CD4+ T cells with the aforementioned DCs to determine the differentiation of Tregs. Additionally, samples from patients with CD were collected to analyse the correlation between TLR5/TSLP/TGFß expression and the percentage of R. intestinalis. FINDINGS: Here, we show that R. intestinalis inhibits the development of CD by increasing the differentiation of anti-inflammatory Tregs. Mechanistically, R. intestinalis stimulates TSLP production in intestinal epithelial cells (IECs) through TLR5 but not TLR2 or TLR4. TSLP produced by IECs specifically induces the secretion of interleukin-10 (IL-10) and TGFß from DCs, which is necessary for subsequent Treg differentiation. Consequently, the depletion of TLR5 (using Tlr5-/- mice) or inhibition of TSLP (using anti-TSLP neutralizing antibodies) attenuates the protective effect of R. intestinalis on experimental colitis in mice. Importantly, the expression of TSLP in patients with CD is positively correlated with the level of R. intestinalis. INTERPRETATION: These findings reveal the previously unknown mechanism of R. intestinalis-mediated intestinal immune regulation, which may provide the basis for new therapeutic strategies for CD. FUNDING: This work was funded by the National Natural Science Foundation of China (81670504 and 81970494), the Key Project of Research and Development Plan of Hunan Province (2019SK2041) and the Changsha Municipal Natural Science Foundation (kq2014258).


Assuntos
Colite , Doença de Crohn , Humanos , Camundongos , Animais , Receptor 5 Toll-Like , Doença de Crohn/patologia , Células CACO-2 , Camundongos Endogâmicos C57BL , Receptor 4 Toll-Like , Citocinas/metabolismo , Colite/patologia , Ácido Trinitrobenzenossulfônico/efeitos adversos , Fator de Crescimento Transformador beta/metabolismo , Mucosa Intestinal/metabolismo
3.
Dig Dis Sci ; 67(1): 56-66, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33609209

RESUMO

Inflammatory bowel disease (IBD) is a chronic and nonspecific intestinal inflammatory condition with high relapse rate. Its pathogenesis has been linked to dysbacteriosis, genetic and environmental factors. In recent years, a new type of lymphocytes, termed innate lymphoid cells, has been described and classified into three subtypes of innate lymphoid cells-group 1, group 2 and group 3. An imbalance among these subsets' interaction with gut microbiome, and other immune cells affects intestinal mucosal homeostasis. Understanding the role of innate lymphoid cells may provide ideas for developing novel and targeted approaches for treatment of IBD.


Assuntos
Imunidade Inata , Doenças Inflamatórias Intestinais , Subpopulações de Linfócitos T/imunologia , Descoberta de Drogas , Humanos , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia
4.
Front Cell Infect Microbiol ; 11: 757718, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34881193

RESUMO

Roseburia intestinalis is an anaerobic, Gram-positive, slightly curved rod-shaped flagellated bacterium that produces butyrate in the colon. R. intestinalis has been shown to prevent intestinal inflammation and maintain energy homeostasis by producing metabolites. Evidence shows that this bacterium contributes to various diseases, such as inflammatory bowel disease, type 2 diabetes mellitus, antiphospholipid syndrome, and atherosclerosis. This review reveals the potential therapeutic role of R. intestinalis in human diseases. Patients with inflammatory bowel disease exhibit significant changes in R. intestinalis abundance, and they may benefit a lot from modulations targeting R. intestinalis. The data reviewed here demonstrate that R. intestinalis plays its role in regulating barrier homeostasis, immune cells, and cytokine release through its metabolite butyrate, flagellin and other. Recent advancements in the application of primary culture technology, culture omics, single-cell sequencing, and metabonomics technology have improved research on Roseburia and revealed the benefits of this bacterium in human health and disease treatment.


Assuntos
Colite , Diabetes Mellitus Tipo 2 , Clostridiales , Humanos
5.
J Gastroenterol Hepatol ; 36(6): 1663-1669, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33295070

RESUMO

BACKGROUND AND AIM: Although endoscopic ultrasound-guided fine-needle biopsy is widely applied, there is no clear consensus on the optimal biopsy technique. We described a modified wet suction technique (MWEST) with the aim to compare the efficacy and safety between MWEST and the dry suction technique (DST). METHODS: In this prospective, randomized, crossover, single-blinded study, patients with suspected pancreatic malignancy were randomized to the DST (group A) or MWEST (group B) for the first pass, and the two techniques were performed alternately. The primary outcome was the comparison of specimen adequacy and diagnostic yield between the techniques. Secondary outcomes included the macroscopic visible core length, blood contamination of specimens, and adverse events of both techniques. RESULTS: From January 2019 to September 2019, 216 passes were performed in 50 patients. The specimen adequacy was significantly higher in "per-lesion" (P = 0.026), "per-pass" (cytology: P = 0.034; histology: P = 0.042), and first-pass analysis (P = 0.034) for MWEST than for DST. In diagnostic yield, MWEST showed significantly superior histological yield (P = 0.014) and first-pass analysis (κ: MWEST: 0.743 and DST: 0.519) compared with DST. The median macroscopic visible core lengths were 8 mm (interquartile range: 3.25-15 mm) and 10 mm (interquartile range: 5.25-15 mm) for DST and MWEST, respectively (P = 0.036). Blood contamination was significantly more serious in DST than in MWEST (cytology: P = 0.021; histology: P = 0.042). CONCLUSIONS: Endoscopic ultrasound-guided fine-needle biopsy with MWEST resulted in significantly better quality of specimen, histological, and first-pass diagnostic yields and comparable safety compared with the DST. MWEST is preferred for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Manejo de Espécimes/métodos , Sucção/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Estudos Prospectivos , Método Simples-Cego
6.
Mol Med Rep ; 22(4): 2695-2704, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32700754

RESUMO

Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD), which is a chronic, relapsing condition associated with the disorder of gut microbial communities. A previous study reported that levels of Roseburia intestinalis (R.I), a butyrate­producing bacterium, are significantly decreased in patients with IBD and exert an anti­inflammatory function in dextran sulfate sodium (DSS)­induced colitis. However, the role of R.I flagellin in UC and its underlying molecular mechanism are not yet fully understood. Therefore, a DSS­induced colitis model in C57Bl/6 mice and the LPS/ATP­induced THP­1 macrophages were treated with R.I flagellin, which were used to investigate the anti­inflammatory effects of R.I flagellin. The results demonstrated that R.I flagellin decreased colitis­associated disease activity index, colonic shortening and the pathological damage of the colon tissues in murine colitis models. Furthermore, R.I flagellin decreased the serum levels of proinflammatory cytokines and inhibited activation of the nucleotide­binding oligomerization segment­like receptor family 3 (NLRP3) inflammasome in murine colitis. R.I flagellin was also demonstrated to decrease the Gasdermin D to yield the N­terminal fragment membrane pore and inhibit inflammasome­triggered pyroptosis. In vitro analysis indicated that microRNA (miR)­223­3p was involved in the regulation of R.I flagellin on NLRP3 inflammasome activation. Taken together, the results of the present study demonstrated that R.I flagellin inhibited activation of the NLRP3 inflammasome and pyroptosis via miR­223­3p/NLRP3 signaling in macrophages, suggesting that R.I flagellin may be used as a novel probiotic product for the treatment of UC.


Assuntos
Anti-Inflamatórios/farmacologia , Clostridiales/química , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Flagelina/farmacologia , MicroRNAs/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Trifosfato de Adenosina/toxicidade , Animais , Colite Ulcerativa/induzido quimicamente , Sulfato de Dextrana/toxicidade , Humanos , Inflamassomos/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Piroptose/efeitos dos fármacos , Células THP-1 , Receptores Toll-Like/metabolismo
7.
Gastroenterol Res Pract ; 2019: 1484598, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885541

RESUMO

BACKGROUND AND AIMS: Probiotics was considered as a potential therapy for nonalcoholic fatty liver disease (NAFLD) without approval and comprehensive assessment in recent years, which call for a meta-analysis. METHODS: We performed electronic and manual searches including English and Chinese databases published before April 2019, with the use of mesh term and free text of "nonalcoholic fatty liver disease" and "probiotics." Clinical trials evaluating the efficacy of probiotic therapy in NAFLD patients were included according to the eligibility criteria. With the use of random effects models, clinical outcomes were presented as weighted mean difference (WMD) with 95% confidence interval (CI), while heterogeneity and meta-regression were also assessed. RESULTS: 28 clinical trials enrolling 1555 criterion proven NAFLD patients with the use of probiotics from 4 to 28 weeks were included. Overall, probiotic therapy had beneficial effects on body mass index (WMD: -1.46, 95% CI: [-2.44, -0.48]), alanine aminotransferase (WMD: -13.40, 95% CI: [-17.03, -9.77]), aspartate transaminase (WMD: -13.54, 95% CI: [-17.86, -9.22]), gamma-glutamyl transpeptidase (WMD: -9.88, 95% CI: [-17.77, -1.99]), insulin (WMD: -1.32, 95% CI: [-2.43, -0.21]), homeostasis model assessment-insulin resistance (WMD: -0.42, 95% CI: [-0.73, -0.12]), and total cholesterol (WMD: -15.38, 95% CI: [-26.50, -4.25]), but not in fasting blood sugar, lipid profiles, or tumor necrosis factor-alpha. CONCLUSION: The systematic review and meta-analysis support that probiotics are superior to placebo in NAFLD patients and could be utilized as a common complementary therapeutic approach.

8.
Biomater Sci ; 7(10): 4174-4185, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31380882

RESUMO

The homeostasis process in the gut tissue of humans relies on intestinal bacteria. However, the intestine is a complex structural tissue with a huge superficial area, and thus the effective application of probiotics in the treatment of Crohn's disease (CD) is still challenging. Herein, we show the feasibility of probiotic target delivery and retention using magnetic iron oxide nanoparticle-internalized Roseburia intestinalis, which can be easily directed by a magnetic field in vitro and in vivo. Subsequently, the increased colonization of this core profitable flora not only resulted in a better therapy effect than traditional intragastric administration but also altered the bacterial composition, leading to a higher diversity in microbial taxa in rats with colitis. Our findings illustrate the exciting opportunities that nanotechnology offers for alternative strategies to modulate biological systems remotely and precisely, which represent a step towards the wireless magnetic manipulation of living biological entities in microbiology.


Assuntos
Clostridiales/fisiologia , Doença de Crohn/microbiologia , Doença de Crohn/terapia , Compostos Férricos/química , Animais , Colite/microbiologia , Colite/terapia , Campos Magnéticos , Masculino , Microscopia Eletrônica de Transmissão , Nanotecnologia/métodos , Probióticos , Ratos , Ratos Sprague-Dawley
9.
Mol Med Rep ; 20(2): 1007-1016, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31173202

RESUMO

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), has a complex etiology that may be associated with dysbiosis of the microbiota. Previously, our study revealed significant loss of Roseburia intestinalis from the gut of untreated patients with CD, and that R. intestinalis exerted anti­inflammatory functions in TNBS­induced colitis; however, the function of R. intestinalis supernatant is unknown. Therefore, LPS­induced macrophages, including RAW264.7 macrophages and bone marrow­derived macrophages were treated with R. intestinalis supernatant. The results indicated that R. intestinalis supernatant suppressed expression of interleukin (IL)­6 and signal transducer and activator of transcription 3 (STAT3) by macrophages. Additionally, these findings were further verified in vivo in DSS­ and TNBS­induced mouse models of colitis. It was observed that R. intestinalis supernatant ameliorated IBD colitis by reducing the number of inflammatory macrophages and Th17 cells in the colon, and by downregulating the expression of IL­6 and STAT3. Finally, the non­protein components of R. intestinalis supernatant were examined using gas chromatography­mass spectrometry analysis and identified the presence of short­chain fatty acids. In conclusion, the results of the present study indicated that R. intestinalis supernatant may regulate immune responses and ameliorate colitis.


Assuntos
Clostridiales/fisiologia , Colite/terapia , Meios de Cultivo Condicionados/farmacologia , Imunidade Inata/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Animais , Clostridiales/química , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Meios de Cultivo Condicionados/química , Sulfato de Dextrana/administração & dosagem , Ácidos Graxos Voláteis/química , Ácidos Graxos Voláteis/isolamento & purificação , Regulação da Expressão Gênica , Interleucina-6/antagonistas & inibidores , Interleucina-6/genética , Interleucina-6/imunologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Células RAW 264.7 , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Transdução de Sinais , Células Th17 , Ácido Trinitrobenzenossulfônico/administração & dosagem
10.
Scand J Gastroenterol ; 54(4): 432-440, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30946611

RESUMO

Objective: Levels of oncostatin M (OSM) and the composition of gut microbiota predict responses to anti-TNF agents used for IBD therapy. Here, the aim was to investigate the effects of Roseburia intestinalis, a gut microbiota, on OSM and on intestinal barrier in colitis. Methods: In the murine model of 3% dextran sulfate sodium (DSS)-induced colitis, we tested disease activity index (DAI), colon length, histological score and expression of tight junction (TJ) proteins (ZO-1, occludin and claudin-1), OSM, TNF-α and TLR5. In addition, a cellular model was used to examine the role of R. intestinalis during secretion of OSM by lipopolysaccharide (LPS)-induced bone marrow-derived macrophages (BMDMs) isolated from wild-type (WT) and TLR5 knockout (TLR5 KO) mice. Furthermore, we evaluated the impact of OSM on expressions of TJ proteins by Caco-2 cells. Results: R. intestinalis in DSS-induced colitis decreased DAI score (p < .001), colon length shortening (6.46 ± 0.36 cm vs 5.65 ± 0.47 cm, p = .022), histological score (2.667 ± 1.15 vs 5.33 ± 1.14, p = .018) and increased expression of TJ proteins (p < .05). In addition, R. intestinalis reduced expression of OSM (p < .05) and TNF-α (p < .05), while increasing expression of TLR5 (p < .05). Furthermore, R. intestinalis reduced secretion of OSM (p < .05) by LPS-induced BMDMs isolated from WT and TLR5 KO mice. Moreover, OSM downregulated expression of TJ proteins (p < .05) by Caco-2 cells in a concentration-dependent manner. Conclusions: These results indicate that R. intestinalis attenuates inflammation in IBD by decreasing secretion of OSM and by promoting intestinal barrier function. Taken together, the data provide insight into the role of the gut microbiota in patients with IBD who are resistant to anti-TNF therapy.


Assuntos
Clostridiales/fisiologia , Colite/metabolismo , Mucosa Intestinal/patologia , Oncostatina M/metabolismo , Junções Íntimas/metabolismo , Animais , Células CACO-2 , Colite/microbiologia , Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Feminino , Humanos , Mucosa Intestinal/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 5 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo
11.
J Sep Sci ; 41(19): 3772-3781, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30152917

RESUMO

A microchip capillary electrophoresis coupled with laser induced fluorescence detection method for the fast determination of aloin was developed and comprehensively applied for the quantification of aloin A and B present in seven aloe plant species, 42 aloin-containing crude drugs, ten aloe pharmaceutical preparations, and four aloe gel-containing functional foods. The excitation and emission wavelengths for detection of both aloins were set at 473 and 520 nm, respectively. Sample analysis on a 35 mm length of glass microchip channel was completed within 40 s. An interference study indicated that the other main anthraquinones present in the samples did not interrupt with the target aloins detection, demonstrating the good selectivity of this method. It is demonstrated that this method is fast, facile, and specific for determination of aloin A and B from matrix samples which can be applied to the quality control of a wide varieties of aloe species and aloe-derived products.


Assuntos
Aloe/química , Bebidas/análise , Eletroforese em Microchip , Emodina/análogos & derivados , Fluorescência , Lasers , Emodina/análise , Conformação Molecular , Extratos Vegetais/química , Espectrometria de Fluorescência
12.
J Chromatogr A ; 1569: 222-228, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30037541

RESUMO

An aptamer-based microchip capillary electrophoresis coupled with laser induced fluorescence (MCE-LIF) detection method for fast determination of Aflatoxin B1 (AFB1) and Ochratoxin A (OTA) was developed. Aptamers that are specific to these two mycotoxins were first hybridized with their aptamer complementary oligonucleotides. The double strand DNA that comes in contact with mycotoxin-containing environment would be unwound into separate aptamer-mycotoxin complex and aptamer complementary single strand. Different types of oligonucleotides can be separated in MCE and detected under the aid of fluorescent dye SYBR gold in LIF detection unit. Under the optimal conditions, on-chip aptamer-mycotoxin conjugates analysis was achieved within 3 min with extremely low LODs (0.026 ng/mL for AFB1 and 0.021 ng/mL for OTA). Specificity study indicated that other major mycotoxins would not cross-react with these two aptamers, demonstrating the good selectivity of the proposed method. Quantification of trace AFB1 and OTA in real food samples was carried out and satisfactory recoveries were obtained. It is demonstrated that this method is fast, facile and specific for Simultaneous determination of trace AFB1 and OTA from foodstuffs.


Assuntos
Aflatoxina B1/análise , Aptâmeros de Nucleotídeos/química , Eletroforese Capilar/métodos , Eletroforese em Microchip/métodos , Análise de Alimentos/métodos , Ocratoxinas/análise , Fluorescência , Corantes Fluorescentes/química , Limite de Detecção , Compostos Orgânicos/química
13.
J Sep Sci ; 40(20): 4022-4031, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28782879

RESUMO

A new, rapid, green, and cost-effective magnetic solid-phase extraction of ochratoxin A from red wine samples was developed using polydopamine-coated magnetic multi-walled carbon nanotubes as the absorbent. The polydopamine-coated magnetic multi-walled carbon nanotubes were fabricated with magnetic multi-walled carbon nanotubes and dopamine by an in situ oxidative self-polymerization approach. Transmission electron microscopy, dynamic light scattering, X-ray photoelectron spectroscopy and vibrating sample magnetometry were used to characterize the absorbents. Ochratoxin A was quantified with high-performance liquid chromatography coupled with fluorescence detection, with excitation and emission wavelengths of 338 and 455 nm, respectively. The conditions affecting the magnetic solid-phase extraction procedure, such as pH, extraction solution, extraction time, absorbent amount, desorption solution and desorption time were investigated to obtain the optimal extraction conditions. Under the optimized conditions, the extraction recovery was 91.8-104.5% for ochratoxin A. A linear calibration curve was obtained in the range of 0.1-2.0 ng/mL. The limit of detection was 0.07 ng/mL, and the limit of quantitation was 0.21 ng/mL. The recoveries of ochratoxin A for spiked red wine sample ranged from 95.65 to 100.65% with relative standard deviation less than 8%. The polydopamine-coated magnetic multi-walled carbon nanotubes showed a high affinity toward ochratoxin A, allowing selective extraction and quantification of ochratoxin A from complex sample matrixes.


Assuntos
Dopamina , Contaminação de Alimentos/análise , Nanotubos de Carbono , Ocratoxinas/isolamento & purificação , Vinho/análise , Extração em Fase Sólida
14.
Artigo em Inglês | MEDLINE | ID: mdl-28277175

RESUMO

Sensitive detection of gizzerosine, a causative agent for deadly gizzard erosion in chicken feeds, is very important to the poultry industry. In this work, a new method was developed based on microchip capillary electrophoresis (MCE) with laser-induced fluorescence (LIF) detection for rapid analysis of gizzerosine, a biogenic amine in fish meals. The MCE separation was performed on a glass microchip using sodium dodecyl sulfate (SDS) as dynamic coating modifier. Separation conditions, including running buffer pH and concentration, SDS concentration, and the separation voltage were investigated to achieve fast and sensitive quantification of gizzerosine. The assay proposed was very quick and could be completed within 65 s. A linear calibration curve was obtained in the range from 0.04 to 1.8 µg ml-1 gizzerosine. The detection limit was 0.025 µg ml-1 (0.025 mg kg-1), which was far more sensitive than those previously reported. Gizzerosine was well separated from other endogenous components in fish meal samples. Recovery of gizzerosine from this sample matrix (n = 3) was determined to be 97.2-102.8%. The results from analysing fish meal samples indicated that the present MCE-LIF method might hold the potential for rapid detection of gizzerosine in poultry feeds.


Assuntos
Ração Animal/análise , Peixes , Fluorescência , Imidazóis/análise , Lasers , Animais , Eletroforese em Microchip
15.
J Sep Sci ; 38(24): 4269-75, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26496363

RESUMO

A facile and highly efficient magnetic solid-phase extraction method has been developed for Z-ligustilide, the major therapeutic agent in Angelica sinensis. The solid-phase adsorbent material used was prepared by conjugating carbon nanotubes with magnetic Fe3 O4 nanoparticles via a hydrothermal reaction. The magnetic material showed a high affinity toward Z-ligustilide due to the π-π stacking interaction between the carbon nanotubes and Z-ligustilide, allowing a quick and selective exaction of Z-ligustilide from complex sample matrices. Factors influencing the magnetic solid-phase extraction such as the amount of the added adsorbent, adsorption and desorption time, and desorption solvent, were investigated. Due to its high extraction efficiency, this method was proved highly useful for sample cleanup/enrichment in quantitative high-performance liquid chromatography analysis. The proposed method had a linear calibration curve (R(2) = 0.9983) over the concentration between 4 ng/mL and 200 µg/mL Z-ligustilide. The accuracy of the method was determined by the recovery, which was from 92.07 to 104.02%, with the relative standard deviations >4.51%.


Assuntos
4-Butirolactona/análogos & derivados , Angelica sinensis/química , Técnicas de Química Analítica/métodos , Magnetismo , Nanotubos de Carbono/química , Raízes de Plantas/química , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , Técnicas de Química Analítica/normas , Microscopia Eletrônica de Transmissão , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Reprodutibilidade dos Testes , Fatores de Tempo
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