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1.
J Oleo Sci ; 70(7): 1007-1012, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-34121031

ABSTRACT

In this study, cation-exchange resin was used to prepare an esterified antioxidant, sinapate ethyl ester (SE), using ethanolic extracts from rapeseed. A concentration of sinapic acid using the cation-exchange resin in 80% ethanol (aq) and subsequent interesterification of the extract in ethanol using the same resin afforded a product with a purity of 64 wt% and 100% of SE yield. Moreover, after purification using preparative thin-layer chromatography, almost 100 wt% purity was obtained. In an auto-oxidation test, purified SE conferred a much higher antioxidative effect on the bulk oil, emphasising the effectiveness of the protocol using cation-exchange resin for the purification.


Subject(s)
Brassica napus/chemistry , Cation Exchange Resins/chemistry , Esters/chemistry , Free Radical Scavengers/chemistry , Plant Extracts/chemistry , Adsorption , Catalysis , Choline/analogs & derivatives , Choline/chemistry , Choline/isolation & purification , Coumaric Acids/chemistry , Coumaric Acids/isolation & purification , Esterification , Esters/chemical synthesis , Free Radical Scavengers/chemical synthesis
2.
Mol Biol (Mosk) ; 54(6): 1037-1045, 2020.
Article in Russian | MEDLINE | ID: mdl-33276367

ABSTRACT

Brassica campestris L. is the important oil-bearing crop in China. Rapeseed cake is the main byproduct of rapeseed oil extraction. As the main active ingredient in rapeseed cake, sinapine has several important biological activities. Therefore, the inhibitory activity of sinapine on tyrosinase in vitro and its free radical-scavenging rate were determined. Tyrosinase activity in A-375 human melanocytes was also investigated and the effects of sinapine on the melanin content and its antioxidant effects on melanin biosynthesis were studied. The results showed that sinapine had significant antioxidant activity. Sinapine significantly inhibited A-375 human melanocytes in a dose-dependent manner. Sinapine inhibited melanin synthesis in A-375 cells by downregulating the mRNA and protein expression of TRP-1, TRP-2, and MITF factors. The results showed that rapeseed cake sinapine inhibited melanin production and could be used as a potential active ingredient in the development of whitening agents.


Subject(s)
Brassica rapa/chemistry , Choline/analogs & derivatives , Melanins/biosynthesis , Melanocytes/drug effects , Cell Line , China , Choline/isolation & purification , Humans
3.
Prep Biochem Biotechnol ; 50(3): 240-245, 2020.
Article in English | MEDLINE | ID: mdl-31709892

ABSTRACT

A new choline oxidase (ChO) and toluidine blue O (TBO) based amperometric choline biosensor was reported in this article. An amperometric choline biosensor with immobilization of TBO (as a mediator), ChO onto polypyrrole-polyvinylsulphonate (PPy-PVS) film was accomplished on the surface of a platinum electrode. ChO was immobilized on PPy-PVS film by cross-linking with glutaraldehyde (GA). TBO was used as the mediator. Choline is oxidized to betaine and hydrogen peroxide in an oxygenated environment by ChO. Mediator reduced by reaction with hydrogen peroxide. The amperometric response was based upon the electrocatalytic properties of TBO. Optimum pH and temperature values were 7.0 and 30 °C, respectively. There was linearity between 1.0 × 10-8 and 2.0 × 10-8 M (R2 = 0.9805). The detection limit of the biosensor was 1.0 × 10-9 M and response time of the biosensor was 200 s. The storage stability and reproducibility of the biosensor were also investigated. Interfering effect of several interferants such as ascorbic acid, uric acid, alanine, dopamine, paracetamol, cysteine, and glucose on the choline biosensor was examined. The developed biosensor was tested in determinations of content in a synthetic blood sample.


Subject(s)
Alcohol Oxidoreductases/chemistry , Biosensing Techniques , Choline/isolation & purification , Tolonium Chloride/chemistry , Choline/chemistry , Humans , Polymers/chemistry , Polyvinyls/chemistry , Pyrroles/chemistry , Sulfonic Acids/chemistry
4.
Food Chem ; 270: 415-419, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30174065

ABSTRACT

Choline is an essential nutrient for the growth and development of the baby, and therefore it is often added to infant formula. In this paper, a novel sensor for choline determination in infant formula is developed based on upconverting nanoparticles (UCNPs) with near infrared luminescence. UCNPs-based detection can avoid the interference of background fluorescence from complex samples, and thus provide high selectivity and sensitivity. It was observed that in the presence of Fe3+, polyacrylic acid coated UCNPs were quenched to 3% of its original intensity. The degree of quenching was among the best for UCNPs. Hydrogen peroxide could oxidize Fe2+ to Fe3+, which caused quenching of the upconversion luminescence. A new H2O2 detection method was thus established. In addition, choline could be hydrolyzed to betaine by choline oxidase, and at the same time produced H2O2, which also caused luminescence quenching through Fe2+ oxidation. Therefore, selective choline sensing was achieved.


Subject(s)
Choline/chemistry , Hydrogen Peroxide/chemistry , Infant Formula/chemistry , Choline/isolation & purification , Humans , Hydrogen Peroxide/isolation & purification , Infant , Infant, Newborn , Nanoparticles/chemistry
5.
Bioresour Technol ; 271: 210-217, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30268813

ABSTRACT

Biomass pretreatment can improve the conversion efficiency of bioenergy production. Liquid hot water (LHW) pretreatment is a truly green pretreatment due to its zero chemical use, but has the disadvantages of low lignin removal and pseudo-lignin formation. A modified liquid hot water (MLHW) process based on in situ synthesis of deep eutectic solvent (DES) could efficiently improve delignification of Roystonea regia leaves (LR) and leaf sheaths (LSR). LSR was less recalcitrant than LR, and its characteristics of higher porosity (34.8%) and thinner cell walls (5.2 µm) for LSR contributed it higher lignin removal (53.6%) and lower choline chloride (ChCl) consumption (H2O-ChCl mass ratio of 2:1) than those (44.6% and 1:2) from LR. Moreover, a great improvement of 309.0% in bio-methane yield was achieved for the MLHW-treated LSR. In addition, in situ DES in MLHW had good biocompatibility with cellulase, microalgae, and yeast.


Subject(s)
Gardens , Lignin/isolation & purification , Lipid Metabolism , Methane/biosynthesis , Arecaceae/metabolism , Choline/isolation & purification , Lipids , Solvents
6.
J Proteome Res ; 17(9): 3223-3236, 2018 09 07.
Article in English | MEDLINE | ID: mdl-30085679

ABSTRACT

Fruits of Lycium ruthenicum (LR) and L. barbarum (LB) in Solanaceae family contain abundant bioactive metabolites used widely as functional food and natural medicine. To characterize the fruit developmental molecular phenotypes, we comprehensively analyzed metabolite composition of both Lycium fruits at three developmental stages using the combined NMR, liquid chromatography-tandem mass spectrometry, and gas chromatography-flame ionization detector/mass spectrometry methods. The metabonomes of these fruits were dominated by over 90 metabolites including sugars, amino acids, tricarboxylic acid (TCA) cycle intermediates, fatty acids, choline metabolites, and shikimate-mediated plant secondary metabolites. Metabolic phenotypes of two species differed significantly at all three developmental stages; LB fruits contained significantly more sugars and amino acids but less TCA cycle intermediates, fatty acids, and secondary metabolites than LR. Interspecies differences for fatty acid levels were much greater after color-breaking than precolor-breaking. Furthermore, LR fruits contained more osmolytes than LB fruits indicating different osmoregulation requirements for these fruits during development. Significant differences were also present in biosynthesis of shikimate-mediated plant secondary metabolites in LR and LB. These findings provided essential metabolic information for plant physiology of these  Lycium species and their utilizations demonstrating the usefulness of this metabonomic phenotyping approach for studying fundamental biochemistry of the plant development.


Subject(s)
Fruit/metabolism , Lycium/metabolism , Metabolome/physiology , Metabolomics/methods , Secondary Metabolism/physiology , Amino Acids/isolation & purification , Amino Acids/metabolism , Choline/analogs & derivatives , Choline/isolation & purification , Choline/metabolism , Chromatography, Liquid , Fatty Acids/isolation & purification , Fatty Acids/metabolism , Fruit/growth & development , Gas Chromatography-Mass Spectrometry , Lycium/classification , Lycium/growth & development , Magnetic Resonance Spectroscopy , Metabolomics/instrumentation , Osmoregulation/physiology , Phenotype , Shikimic Acid/isolation & purification , Shikimic Acid/metabolism , Species Specificity , Sugars/isolation & purification , Sugars/metabolism , Tandem Mass Spectrometry , Tricarboxylic Acids/isolation & purification , Tricarboxylic Acids/metabolism
7.
Pancreas ; 46(8): 1046-1055, 2017 09.
Article in English | MEDLINE | ID: mdl-28797013

ABSTRACT

OBJECTIVES: We set out to examine whether berberine (BBR) might affect the severity of pancreatitis and pancreatitis-associated lung injury in choline-deficient ethionine-supplemented (CDE) diet-induced severe acute pancreatitis. METHODS: Severe acute pancreatitis was induced by feeding a CDE diet for 3 days. Berberine was administered intraperitoneally during CDE diet. Mice were killed on days 1, 2, and 3 after the onset of CDE diet. The severity of pancreatitis was assessed by evaluating changes to the pancreas and lung and survival rate. Blood, pancreas, and lung were harvested for further examination. Furthermore, the regulating mechanisms of BBR were evaluated on the pancreas. RESULTS: Administration of BBR significantly inhibited histological damage to the pancreas and lung and decreased serum level of amylase and lipase, myeloperoxidase activity, cytokine production, and the mortality rate. Furthermore, administration of BBR inhibited activation of nuclear factor kappa B, c-Jun N-terminal kinases, and p38 in the pancreas during CDE diet. CONCLUSIONS: These findings suggest that BBR attenuates the severity of pancreatitis by inhibiting activation of nuclear factor kappa B, c-Jun N-terminal kinase, and p38 and that BBR could be used as a beneficial agent to regulate AP.


Subject(s)
Berberine/pharmacology , Lung Injury/prevention & control , Lung/drug effects , Pancreas/drug effects , Pancreatitis, Acute Necrotizing/prevention & control , Amylases/blood , Animals , Choline/isolation & purification , Diet/adverse effects , Ethionine/administration & dosage , Female , Lipase/blood , Lung/metabolism , Lung/pathology , Lung Injury/mortality , Mice, Inbred C57BL , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/metabolism , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Pancreas/metabolism , Pancreas/pathology , Pancreatitis, Acute Necrotizing/etiology , Pancreatitis, Acute Necrotizing/mortality , Phytotherapy/methods , Survival Rate
8.
Food Chem ; 201: 185-9, 2016 Jun 15.
Article in English | MEDLINE | ID: mdl-26868564

ABSTRACT

Acetylcholine (AcCh) is a major neurotransmitter and an agonist of nicotinic and muscarinic receptors in non-neuronal systems. Artificially synthesized lactoylcholine (LaCh) has potent nicotinic activity equal to that of AcCh. In this study, we report the isolation and purification of natural AcCh and LaCh from a lactic-fermented food known to reduce blood pressure. To our knowledge, we are the first to isolate natural LaCh. The choline esters were isolated using a novel purification procedure combining a weak cation-exchange cartridge with ODS and pentafluorophenyl HPLC columns, and the structure of LaCh was identified via various analyses. Assessment of D- and L-LaCh showed that the isolated LaCh was an enantiomer mixture with a D/L ratio of 1.6. D-LaCh induced vasorelaxation of thoracic aortas from spontaneously hypertensive rats (EC50=3.83×10(-7) M), while L-LaCh did not. Our results suggest that choline esters could be new functional ingredients in lactic-fermented foods.


Subject(s)
Choline/chemistry , Fermentation , Food Analysis , Lactic Acid/chemistry , Lactobacillaceae/metabolism , Acetylcholine/analysis , Acetylcholine/chemistry , Animals , Choline/isolation & purification , Food Microbiology , Lactic Acid/isolation & purification , Male , Rats , Rats, Inbred SHR , Vasodilation/drug effects
9.
Biosens Bioelectron ; 52: 304-9, 2014 Feb 15.
Article in English | MEDLINE | ID: mdl-24080209

ABSTRACT

A simple and novel method is proposed for the preparation of Carbon dots (C-dots) with excellent properties. We firstly demonstrated that the fluorescence of C-dots decreased apparently in the presence of H2O2 and Fe(2+). Based on the this finding, C-dots are successfully adopted as probes for the detection of H2O2. After the experimental conditions are optimized, the limit of detection (LOD) for H2O2 is found to be 0.1 µM. Furthermore, we established an eco-friendly, simple and sensitive biosensor for the detection of choline and acetylcholine (ACh) based on the detection of H2O2 using C-dots as probes. The detection limit for choline is 0.1 µM and the linear range is 0.1-40 µM. The detection limit for ACh is found to be 0.5 µM and the linear range is 0.5-60 µM. The excellent performance of the proposed biosensor shows that this method possesses the potential for practical application.


Subject(s)
Acetylcholine/isolation & purification , Biosensing Techniques/methods , Choline/isolation & purification , Acetylcholine/chemistry , Carbon/chemistry , Choline/chemistry , Fluorescence , Fluorescent Dyes/chemistry , Humans , Hydrogen Peroxide/chemistry
10.
Anal Cell Pathol (Amst) ; 36(3-4): 71-83, 2013.
Article in English | MEDLINE | ID: mdl-24036926

ABSTRACT

It has been repeatedly demonstrated that choline metabolism is altered in a wide variety of cancers. In breast tumours, the choline metabolite profile is characterized by an elevation of phosphocholine and total choline-compounds. This pattern is increasingly being exploited as biomarker in cancer diagnosis. The majority of in vitro metabolomics studies, for biomarkers quantification in cell cultures or tissues, entail proton NMR spectroscopy. Although many "targeted" approaches have been proposed to quantify metabolites from standard one-dimensional (1D) NMR experiments, the task is often made difficult by the high degree of overlap characterizing 1H NMR spectra of biological samples. Here we present an optimized protocol for tissue extraction and absolute quantification of choline, phosphocholine and glycerophosphocholine by means of liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS). The selected chromatographic separation system with a HILIC (hydrophilic interaction chromatography) amide column effectively separates free choline and its phopshorylated derivatives, contrary to failure observed using standard reversed-phase chromatography. The metabolite absolute quantification is based on external calibration with commercial standards, and is validated by a parallel 1D proton NMR analysis. The LC-MS/NMR analysis is applied to three breast carcinoma specimens obtained by surgical excision, each one accompanied by a control tissue sample taken outside the tumor margin. The metabolite concentrations measured are in good agreement with previous results on metabolic profile changes of breast cancer. Each of the three cancerous biopsies, when compared with the control tissue, exhibit a highly increased levels phosphocholine, total choline and phosphocholine/glycerophosphocholine ratio.


Subject(s)
Biomarkers, Tumor/analysis , Breast Neoplasms/chemistry , Carcinoma, Ductal, Breast/chemistry , Carcinoma, Lobular/chemistry , Choline/analysis , Chromatography, Liquid/methods , Glycerylphosphorylcholine/analysis , Phosphorylcholine/analysis , Spectrometry, Mass, Electrospray Ionization/methods , Acetonitriles , Biopsy , Breast/chemistry , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Ductal, Breast/pathology , Carcinoma, Lobular/metabolism , Carcinoma, Lobular/pathology , Choline/isolation & purification , Choline/metabolism , Female , Glycerylphosphorylcholine/isolation & purification , Humans , Metabolomics/methods , Nuclear Magnetic Resonance, Biomolecular , Phosphorylcholine/isolation & purification , Solvents
11.
Appl Radiat Isot ; 78: 26-32, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23665261

ABSTRACT

INTRODUCTION: A novel one-pot method for preparing [(18)F]fluoromethylcholine ([(18)F]FCH) via in situ generation of [(18)F]fluoromethyl tosylate ([(18)F]FCH2OTs), and subsequent [(18)F]fluoromethylation of dimethylaminoethanol (DMAE), has been developed. METHODS: [(18)F]FCH was prepared using a GE TRACERlab FXFN, although the method should be readily adaptable to any other fluorine-(18) synthesis module. Initially ditosylmethane was fluorinated to generate [(18)F]FCH2OTs. DMAE was then added and the reaction was heated at 120 °C for 10 min to generate [(18)F]FCH. After this time, reaction solvent was evaporated, and the crude reaction mixture was purified by solid-phase extraction using C(18)-Plus and CM-Light Sep-Pak cartridges to provide [(18)F]FCH formulated in USP saline. The formulated product was passed through a 0.22 µm filter into a sterile dose vial, and submitted for quality control testing. Total synthesis time was 1.25 h from end-of-bombardment. RESULTS: Typical non-decay-corrected yields of [(18)F]FCH prepared using this method were 91 mCi (7% non-decay corrected based upon ~1.3 Ci [(18)F]fluoride), and doses passed all other quality control (QC) tests. CONCLUSION: A one-pot liquid-phase synthesis of [(18)F]FCH has been developed. Doses contain extremely low levels of residual DMAE (31.6 µg/10 mL dose or ~3 ppm) and passed all other requisite QC testing, confirming their suitability for use in clinical imaging studies.


Subject(s)
Choline/analogs & derivatives , Deanol/chemistry , Deanol/isolation & purification , Drug Contamination/prevention & control , Isotope Labeling/instrumentation , Robotics/instrumentation , Choline/chemical synthesis , Choline/isolation & purification , Equipment Design , Equipment Failure Analysis , Isotope Labeling/methods , Robotics/methods
12.
J Proteome Res ; 12(6): 2980-6, 2013 Jun 07.
Article in English | MEDLINE | ID: mdl-23631600

ABSTRACT

Reversed-phase gradient LC-MS was used to perform untargeted metabonomic analysis on extracts of human colorectal cancer (CRC) cell lines (COLO 205, HT-29, HCT 116 and SW620) subcutaneously implanted into age-matched athymic nude male mice to study small molecule metabolic profiles and examine possible correlations with human cancer biopsies. Following high mass accuracy data analysis using MS and MS/MS, metabolites were identified by searching against major metabolite databases including METLIN, MASSBANK, The Human Metabolome Database, PubChem, Biospider, LipidMaps and KEGG. HT-29 and COLO 205 tumor xenografts showed a distribution of metabolites that differed from SW620 and HCT 116 xenografts (predominantly on the basis of relative differences in the amounts of amino acids and lipids detected). This finding is consistent with NMR-based analysis of human colorectal tissue, where the metabolite profiles of HT-29 tumors exhibit the greatest similarity to human rectal cancer tissue with respect to changes in the relative amounts of lipids and choline-containing compounds. As the metabolic signatures of cancer cells result from oncogene-directed metabolic reprogramming, the HT-29 xenografts in mice may prove to be a useful model to further study the tumor microenvironment and cancer biology.


Subject(s)
Biomarkers, Tumor/isolation & purification , Colorectal Neoplasms/metabolism , Metabolome , Amino Acids/isolation & purification , Animals , Biopsy , Cell Line, Tumor , Choline/isolation & purification , Chromatography, Liquid , Colorectal Neoplasms/chemistry , Colorectal Neoplasms/pathology , Databases, Factual , Humans , Lipids/isolation & purification , Magnetic Resonance Spectroscopy , Male , Mice , Mice, Nude , Neoplasm Transplantation , Organ Specificity , Principal Component Analysis , Tandem Mass Spectrometry , Transplantation, Heterologous , Tumor Microenvironment
13.
J Food Sci ; 78(4): E542-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23488824

ABSTRACT

Brassicaceae oilseeds provide feedstocks for the biofuels industry, but value-added coproducts are necessary to supply financial incentives for increased production. Our objective was to use high-intensity ultrasound to optimize extraction of antioxidants from mustard (Brassica juncea) seed meal. The ultrasound-assisted extraction (UAE) variables included temperature, solvent-to-material ratio, sonication duration, and EtOH concentration. Extracts were analyzed for total phenolics content (TPC), antioxidant activity, and sinapine content. Conventional extraction using water and 70% EtOH (v/v) at 80 °C for 3×30 min yielded 7.83 ± 0.07 and 8.81 ± 0.17 mg sinapic acid equivalents (SAE)/g meal, respectively. UAE extraction at 40 °C for 30 min yielded similar phenolics content (8.85 ± 0.33 mg SAE/g meal) as conventional hot ethanolic extraction, but required less time and lower temperature. The highest TPC (13.79 ± 0.38 mg SAE/g meal) was in the 7-d aqueous extracts. Sonicated solutions of pure sinapine and sinapic acid showed 1st-order reaction kinetics with greater degradation of isolated compounds than those present in extracts. Sinapine contained in extracts showed insignificant (P < 0.05) degradation after 30 min of sonication. Our research indicates that ultrasound treatment can assist the extraction of antioxidants from B. juncea meal by reducing both the temperature and time requirement without significant degradation of the primary antioxidants present.


Subject(s)
Antioxidants/isolation & purification , Mustard Plant/chemistry , Plant Extracts/analysis , Seeds/chemistry , Antioxidants/analysis , Choline/analogs & derivatives , Choline/analysis , Choline/isolation & purification , Chromatography, High Pressure Liquid , Coumaric Acids/analysis , Coumaric Acids/isolation & purification , Ethanol , High-Energy Shock Waves , Hot Temperature , Phenols/analysis , Phenols/isolation & purification , Sonication/methods , Ultrasonics/methods
14.
Zhongguo Zhong Yao Za Zhi ; 37(12): 1771-4, 2012 Jun.
Article in Chinese | MEDLINE | ID: mdl-22997822

ABSTRACT

OBJECTIVE: To investigate action of hydrophilic constituents from Coptidis Rhizoma on glucose-lowering effect metabolism of berberine in HepG2 cells. METHOD: Hydrophilic fractions of Coptidis Rhizoma were prepared by high speed counter current chromatography and separated by silica gel column chromatography. MTT assay was used to monitor the proliferation of HepG2 cells, and Kit was used to test the glucose consumption in culture solution. RESULT: Choline was separated from Coptidis Rhizoma for the first time. Cell assay showed choline can significantly increase the glucose lowering effect of berberine and improve the cytotoxicity of berberine within test concentration. Compared with same dose of berberine, berberine 38 mg x L(-1) in combination with choline 100 mg x L(-1) can make glucose consumption increase by 34% and elevate cell livability up to 75% in HepG2 cells. CONCLUSION: The results suggest that choline had a synergistic effect on improving glucose absorption of berberine and decreasing cytotoxicity of berberine.


Subject(s)
Berberine/pharmacology , Choline/isolation & purification , Choline/pharmacology , Drugs, Chinese Herbal/chemistry , Glucose/metabolism , Absorption/drug effects , Cell Proliferation/drug effects , Choline/analysis , Choline/chemistry , Chromatography, High Pressure Liquid , Coptis chinensis , Drug Synergism , Hep G2 Cells , Humans , Hydrophobic and Hydrophilic Interactions
15.
J Chromatogr A ; 1247: 18-25, 2012 Jul 20.
Article in English | MEDLINE | ID: mdl-22677413

ABSTRACT

The aim of this article was to evaluate the influence of the column design of a hydrostatic support-free liquid-liquid chromatography device on the process efficiency when the strong ion-exchange (SIX) development mode is used. The purification of p-hydroxybenzylglucosinolate (sinalbin) from a crude aqueous extract of white mustard seeds (Sinapis alba L.) was achieved on two types of devices: a centrifugal partition chromatograph (CPC) and a centrifugal partition extractor (CPE). They differ in the number, volume and geometry of their partition cells. The SIX-CPE process was evaluated in terms of productivity and sinalbin purification capability as compared to previously optimized SIX-CPC protocols that were carried out on columns of 200 mL and 5700 mL inner volume, respectively. The objective was to determine whether the decrease in partition cell number, the increase in their volume and the use of a "twin cell" design would induce a significant increase in productivity by applying higher mobile phase flow rate while maintaining a constant separation quality. 4.6g of sinalbin (92% recovery) were isolated from 25 g of a crude white mustard seed extract, in only 32 min and with a purity of 94.7%, thus corresponding to a productivity of 28 g per hour and per liter of column volume (g/h/LV(c)). Therefore, the SIX-CPE process demonstrates promising industrial technology transfer perspectives for the large-scale isolation of ionized natural products.


Subject(s)
Centrifugation/instrumentation , Centrifugation/methods , Chemical Fractionation/methods , Chromatography, Ion Exchange/methods , Choline/analogs & derivatives , Choline/isolation & purification , Countercurrent Distribution/methods , Models, Chemical , Mustard Plant/chemistry , Seeds/chemistry
16.
Anal Bioanal Chem ; 403(8): 2103-12, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22286077

ABSTRACT

Choline is a quaternary amine that is synthesized in the body or consumed through the diet. Choline is critical for cell membrane structure and function and in synthesis of the neurotransmitter acetylcholine. Although the human body produces this micronutrient, dietary supplementation of choline is necessary for good health. The major challenge in the analysis of choline in foods and dietary supplements is in the extraction and/or hydrolysis approach. In many products, choline is present as choline esters, which can be quantitated individually or treated with acid, base, or enzymes in order to release choline ions for analysis. A critical review of approaches based on extraction and quantitation of each choline ester as well as hydrolysis-based methods for determination of total choline in foods and dietary supplements is presented.


Subject(s)
Choline/analysis , Dietary Supplements/analysis , Food Analysis/methods , Biosensing Techniques/methods , Chemical Fractionation/methods , Choline/isolation & purification , Colorimetry/methods , Electrochemical Techniques/methods , Humans , Mass Spectrometry/methods
17.
Nucl Med Biol ; 38(5): 637-44, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21718938

ABSTRACT

INTRODUCTION: The validation and confirmation of clinical usefulness of new and known positron emission tomography (PET) tracers require stable production routes and simple and robust radiochemical procedures. Microfluidic technologies are regarded as an approach that could allow an unprecedented flexibility and productivity in PET radiopharmaceutical research. In this work, we will show how a commercially available microfluidic system can be used for a sequential and repeatable radiosynthesis of three different fluorocholine analogues currently under investigation as tumor tracers. METHODS: Advion microfluidic system was used for performing the synthesis and purification of [(18)F]fluoromethyl, [(18)F]fluoroethyl or [(18)F]fluoropropyl choline employing a two-step approach, starting from the corresponding alkyl-ditosylate and reacting the [(18)F]fluorotosylate obtained in the first step with neat dimethylethanolamine. The purification was obtained using a recyclable SPE cartridge set. RESULTS: The three products, fluoromethylcholine, fluoroethylcholine and fluoropropylcholine, were obtained in good to optimum yields (22%-54% decay corrected) with a 15-min procedure. The production could be restarted several times for producing each one of the tracers without decrease in yields and purities, in accordance with a dose-on-demand (DOD) approach. The final products were formulated in isotonic saline solution. CONCLUSION: The described approach gives a proof of principle of the enhanced productivity obtainable using a microfluidic approach; in particular, the possibility to produce the reported tracers in a DOD fashion following a homogeneous synthetic and purification approach will foster further studies on the clinical evaluation of the best fluorocholine analogue for prostate cancer imaging without biasing for differences in radiochemical approach.


Subject(s)
Choline/analogs & derivatives , Microfluidic Analytical Techniques/methods , Radiochemistry/instrumentation , Choline/chemical synthesis , Choline/chemistry , Choline/isolation & purification , Halogenation , Positron-Emission Tomography , Solid Phase Extraction
18.
Nucl Med Biol ; 38(2): 165-70, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21315271

ABSTRACT

INTRODUCTION: 2-[(18)F]Fluoroethyl-choline ([(18)F]FECH) is a promising tracer for the detection of prostate cancer as well as brain tumors with positron emission tomography (PET). [(18)F]FECH is actively transported into mammalian cells, becomes phosphorylated by choline kinase and gets incorporated into the cell membrane after being metabolized to phosphatidylcholine. So far, its synthesis is a two-step procedure involving at least one HPLC purification step. To allow a wider dissemination of this tracer, finding a purification method avoiding HPLC is highly desirable and would result in easier accessibility and more reliable production of [(18)F]FECH. METHODS: [(18)F]FECH was synthesized by reaction of 2-bromo-1-[(18)F]fluoroethane ([(18)F]BFE) with dimethylaminoethanol (DMAE) in DMSO. We applied a novel and very reliable work-up procedure for the synthesis of [(18)F]BFE. Based on a combination of three different solid-phase cartridges, the purification of [(18)F]BFE from its precursor 2-bromoethyl-4-nitrobenzenesulfonate (BENos) could be achieved without using HPLC. Following the subsequent reaction of the purified [(18)F]BFE with DMAE, the final product [(18)F]FECH was obtained as a sterile solution by passing the crude reaction mixture through a combination of two CM plus cartridges and a sterile filter. The fully automated synthesis was performed using as well a Raytest SynChrom module (Raytest, Germany) or a Scintomics HotboxIII module (Scintomics, Germany). RESULTS: The radiotracer [(18)F]FECH can be synthesized in reliable radiochemical yields (RCY) of 37±5% (Synchrom module) and 33±5% (Hotbox III unit) in less than 1 h using these two fully automated commercially available synthesis units without HPLC involvement for purification. Detailed quality control of the final injectable [(18)F]FECH solution proved the high radiochemical purity and the absence of Kryptofix2.2.2, DMAE and DMSO used in the course of synthesis. Sterility and bacterial endotoxin testing following standard procedures verified that the described production method for [(18)F]FECH is suitable for human applications. CONCLUSIONS: The routine production of [(18)F]FECH with sufficient RCYs was established by reliable and fast solid-phase extraction purifications of both the secondary labeling precursor [(18)F]BFE and the final product [(18)F]FECH, avoiding complex and sensitive HPLC equipment. The purity of the product was >95%, rendering the tracer suitable for human application. The newly developed purification procedure for [(18)F]BFE significantly reduces the complexity of the automated synthesis unit, hence reducing the cost for routine production in a clinical setup and allowing easy transfer to different synthesis modules.


Subject(s)
Choline/analogs & derivatives , Solid Phase Extraction/methods , Automation , Choline/chemical synthesis , Choline/isolation & purification , Deanol/chemistry , Fluorocarbons/chemistry , Humans , Radiochemistry , Safety
19.
Nucl Med Biol ; 37(3): 309-15, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20346870

ABSTRACT

UNLABELLED: [(18)F]-labelled choline analogues, such as 2-[(18)F]fluoroethylcholine ((18)FECH), have suggested to be a new class of choline derivatives highly useful for the imaging of prostate and brain tumours. In fact, tumour cells with enhanced proliferation rate usually exhibit an improved choline uptake due to the increased membrane phospholipids biosynthesis. The aim of this study was the development of a high yielding synthesis of (18)FECH. The possibility of shortening the synthesis time by reacting all the reagents in a convenient and rapid one-step reaction was specially considered. METHODS: (18)FECH was synthesized by reacting [(18)F]fluoride with 1,2-bis(tosyloxy)ethane and N,N-dimethylaminoethanol. The synthesis was carried out using both a one- and a two-step reaction in order to compare the two procedures. The effects on the radiochemical yield and purity by using different [(18)F]fluoride phase transfer catalysts, reagents amounts and purification methods were assessed. Quality controls on the final products were performed by means of radio-thin-layer chromatography, gas chromatography and high-performance liquid chromatography equipped with conductimetric, ultraviolet and radiometric detectors. RESULTS: In the optimized experimental conditions, (18)FECH was synthesized with a radiochemical yield of 43+/-3% and 48+/-1% (not corrected for decay) when the two-step or the one-step approach were used, respectively. The radiochemical purity was higher than 99% regardless of the different synthetic pathways or purification methods adopted. The main chemical impurity was due to N,N-dimethylmorpholinium. The identity of this impurity in (18)FECH preparations was not previously reported. CONCLUSION: An improved two-step and an innovative one-step reaction for synthesizing (18)FECH in a high yield were reported. The adaptation of a multistep synthesis to a single step process, opens further possibilities for simpler and more reliable automations.


Subject(s)
Choline/analogs & derivatives , Isotope Labeling/methods , Robotics/methods , Choline/chemical synthesis , Choline/isolation & purification , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/isolation & purification
20.
J Sep Sci ; 32(11): 1801-7, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19479767

ABSTRACT

The purification of p-hydroxybenzylglucosinolate (sinalbin) on a multigram scale from a crude aqueous extract of white mustard seeds (Sinapis alba var. concerta) was successfully achieved by scaling up a strong ion-exchange centrifugal partition chromatography (SIXCPC) laboratory procedure. Thus, the one-step sinalbin purification was performed with 2.35 g of crude extract in approximately 170 min (830 mg/h) up to 70.3 g in approximately 160 min (26.3 g/h) by switching from a 200 mL laboratory scale column to a 5.7 L pilot-scale column. The required biphasic solvent system contained ethyl acetate, n-butanol, and water in 3:2:5 v/v/v proportions, Aliquat 336 (trioctylmethyl ammonium chloride) was added to the organic stationary phase (80 mM) and acted as ion-exchanger. Potassium iodide in the aqueous mobile phase (80 mM) was used as sinalbin displacer. The 28.5 mass scale factor arose from the increase in mobile phase flow-rate (from 2 to 50 mL/min), from the higher mass of injected white mustard seed extract (from 12 to 350 g), and from the calculated productivity (from 830 mg to 26.3 g). These results demonstrate that industry scale production of glucosinolates is easily performed by SIXCPC, thus providing pure reference standards for pharmacology studies.


Subject(s)
Choline/analogs & derivatives , Chromatography, Ion Exchange/methods , Mustard Plant/chemistry , Seeds/chemistry , Choline/isolation & purification , Chromatography, Ion Exchange/instrumentation , Molecular Conformation , Pilot Projects , Time Factors
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