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Folates are important micronutrients in lentils (Lens culinaris Medik.). In this work, the folate extraction workflow in ascorbate-containing buffer was optimized and validated, and the concentrations of eight folate monoglutamates in cultivated and six wild lentil species, grown under field or greenhouse conditions, were quantified by ultra-performance liquid chromatography and mass spectrometry (UPLC-MS). In general wild lentil species had higher folate concentrations than cultivated genotypes. Lens tomentosus had the highest folate concentration with median values of 439.7 and 360.9 μg/100 g in the field and greenhouse, followed by Lens orientalis with 416.6 and 327.6 μg/100 g, respectively. A significant effect (P < 0.05) of growing conditions was observed in four out of six wild lentil species, with seeds from the field having higher folate concentration (6% to 45%) compared with the greenhouse. MeFox, an oxidation product of 5-methyltetrahydrofolate, was present in all lentil species at concentrations 2.2 to 5.6 times higher than the total folates. • This is the first report of folate quantification in wild lentil species. • Wild lentil species had higher folate concentrations than cultivated ones. • Four out of 6 wild lentils have higher folate concentrations in the field vs greenhouse. • MeFox is microbiologically inactive, but present at higher levels than all folates. • A simplified one-enzyme treatment for folate extraction from pulse seeds. [ABSTRACT FROM AUTHOR]

Macroscopic monoliths are highly desirable in many fields of application. Herein, well organized organic–inorganic cryogel composite with a three‐dimensional hierarchical meso‐ and macroporous structure are presented, which were produced by in situ copolymerization of mesoporous multifunctional silica (size: 1–20 μm; pore: 2–20 nm mostly) and monomers (hydroxyethyl methacrylate and diallyldimethylammonium chloride) in water below the freezing point. This copolymerization method effectively adjusted the macropores of the basic cryogel, and the nanosilica was more homogeneously dispersed in the basic cryogel. The specific surface area of the cryogel composite was increased 17 times versus than that of the basic cryogel. The abundant meso‐ and macroporous pores on the cryogel composite provided sufficient reactive sites favorable for the efficient mass transport of target compounds. When the cryogel composite, as solid phase extraction adsorbent, was coupled with high‐performance liquid chromatography, an analytical tool, the nucleosides were quantified with good selectivity, lower detection limits (0.9–1.3 ng/mL) and satisfactory recoveries of greater than 80% from spiked human serum. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Gynura segetum ( GS ) is an herbal medicine containing Pyrrolizidine Alkaloids (PAs) that causes hepatic sinusoidal obstruction syndrome (HSOS). Aim of the study To discover potential biomarkers and metabolic mechanisms involved in the hepatotoxicity induced by GS . Methods SD rats were randomly divided into 4 groups including Saline, the decoction of GS high, medium and low dosage at dosages of 3.75 g • kg −1 , 7.5 g • kg −1 and 15 g • kg −1 . A metabolomics approach using Ultraperformance Liquid Chromatography -Quadrupole-Time-of-Flight / Mass Spectrometry (UPLC-Q-TOF/MS) was developed to perform the plasma and urinary metabolic profiling analysis, and identified differential metabolites by comparing the saline control group and decoction of GS groups. Results The herbal was presented dosage-dependent led to ingravescence of hepatotoxicity after the rats were consecutively given with the decoction of GS at varied dosages. A total of 18 differential metabolites of decoction of GS -induced hepatotoxicity were identified, while 10 of them including arginine, proline, glutamate, creatine, valine, linoleic acid, arachidonic acid, sphinganine, phytosphingosine, and citric acid could be discovered in urine and plasma, and primarily involved in Amino acid metabolism, Lipids metabolism and Energy metabolism. Conclusions The results suggested that the differential metabolites of arginine, creatine, valine, glutamine and citric acid were verified as potential markers of GS-induced hepatotoxicity via the regulation of multiple metabolic pathways primarily involving in Amino acids metabolism and Energy metabolism. [ABSTRACT FROM AUTHOR]

The synthesis and evaluation of a molecularly imprinted polymer (MIP) as a selective matrix solid-phase dispersion (MSPD) sorbent, coupled with high-performance liquid chromatography for the efficient determination of chloramphenicol (CAP) in fish tissues are studied. The polymer was prepared using CAP as the template molecule, vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer, and sodium dodecyl sulfate as the surfactant in the presence of water as a solvent by miniemulsion polymerization. The CAP-imprinted polymers and nonimprinted polymers (NIPs) were characterized by Fourier transform IR spectroscopy, scanning electron microscopy, and static adsorption experiments. The CAP-imprinted material prepared showed high adsorption capacity, significant selectivity, and good site accessibility. The maximum static adsorption capacity of the CAP-imprinted and the NIP material for CAP was 78.4 and 59.9 mg g-1, respectively. The relative selectivity factors of this CAP-imprinted material were larger than 1.9. Several parameters influencing the MSPD process were optimized. Finally, the CAP-imprinted polymers were used as the sorbent in MSPD to determine CAP in three kinds of fishes and resulted in satisfactory recovery in the range 89.8–101.43%. CAP-imprinted polymer as a sorbent in MSPD is better than C18 and attapulgite in terms of both recovery and percent relative standard deviation. The baseline noise was measured from a chromatogram of a blank fish sample which was treated after the MSPD procedure using CAP-imprinted polymer as a sorbent. Signal values of 3 times the noise (signal-to-noise ratio of 3) and 10 times the noise (signal-to-noise ratio of 10) were used to calculate the limit of detection and the limit of quantitation of the calibration curve. The limit of detection for CAP was 1.2 ng g-1 and the limit of quantitation was 3.9 ng g-1. [ABSTRACT FROM AUTHOR]

Solid-phase microextraction coupled to high-performance liquid chromatography (SPME-HPLC) with fluorescence detection was employed to determine bisphenol A (BPA) in milk samples. The potential influence of the milk matrix on the determination of BPA by SPME-HPLC were investigated. Optimal conditions to eliminate any matrix effects were as follows: milk samples were deproteinized with trichloroacetic acid, diluted 20-fold with BPA-free Ultrapure water, dissolved in methanol, the precipitated protein was filtered out, rinsed with methanol and evaporated to remove the methanol. Then, a 40.0-ml solution was used for SPME extraction and HPLC analysis. Satisfactory recoveries (milk: 93.1-101%; soybean milk: 93.9-102%) were achieved. The proposed method was successfully applied to real samples, BPA being detected within the range 1.6-2.6 ng ml-1 in four brands of commercial milk but not in soybean milk. [ABSTRACT FROM AUTHOR]

A high performance liquid chromatographic method (HPLC) with precolumn derivatization and fluorescence detection for insulin was developed and applied for the quantification of insulin in spiked serum. To covalence couple with insulin, 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole (NBD‐Cl) was selected as fluorescent reagent. The optimal derivatization conditions were as follows: temperature 50; time 2 h, in the dark; 0.1 M phosphate buffer (pH 9.0). Analytical separation was carried out on a C18 column and the mobile phase including acetonitrile‐water containing 0.1% trifluoroacetic acid (TFA) (v/v&ratio; 30/70). The excitation/emission wavelengths were 470/540 nm. Under the conditions, the retention time and capacity factor of the adduct of insulin‐NBD were 10.03 min (flow rate 1 mL/min) and 3, respectively. The recovery of insulin in serum was 95.06% and the detection limit was 90 nM. In the investigated concentration ranges (0.46 µM&nvsim;16.10 µM), R 2 was 0.9934, which indicated the potential for the application of NBD‐Cl derivatization to the analysis of insulin in the biological matrices, although with the shortcoming of long analytical time. [ABSTRACT FROM AUTHOR]

Folates are water-soluble B vitamins and act as cofactors in many metabolic functions in the human body. Pulses have traditionally been considered as a good dietary source of folates. The objectives of this study were (1) to determine the concentration of folates in four cultivars each of common bean, lentil, chickpea and pea, and (2) to determine the effect of growing location on folate concentration. Six folate monoglutamates were quantified by ultra-performance liquid chromatography coupled with mass spectrometry (UPLC–MS/MS). Total folate concentration ranged from 351 to 589 μg/100 g in chickpea, 165 to 232 μg/100 g in common bean, 136 to 182 μg/100 g in lentil, and 23 to 30 μg/100 g in pea. The 5-methyltetrahydrofolate (5-MTHF) and 5-formyltetrahydrofolate (5-FTHF) folates were most abundant in common bean, lentil and chickpea, whereas 5-MTHF and tetrahydrofolate (THF) were the predominant forms in pea. Significant differences were detected among cultivars for all folates across the pulses, except for 5,10-methenyltetrahydrofolate (5,10-MTHF) in lentil, 5-MTHF in chickpea, and 5,10-MTHF and folic acid (FA) in pea. Significant effects for location and cultivar by location were also observed for the majority of the folates. [ABSTRACT FROM AUTHOR]

Background Shiitake, the second most cultivated mushroom, is famous for its high nutritional value and medicinal properties. In this study, various chemical parameters and antioxidant properties of caps and stipes of shiitake mushroom dried by different methods (freeze-drying, shade drying and hot air drying) were comparatively investigated by spectrophotometric assays, high-performance liquid chromatography, 1,1′-diphenyl-2-picrylhydrazyl assay, ferric reducing power assay and lipid peroxidation inhibition assay. Results The contents of amino acids, neutral sugar and total phenolics in stipes were higher than those in caps of shiitake, while caps showed advantages in terms of their contents of protein and eritadenine. The chemical parameters and antioxidant activities of shiitake were significantly affected by the drying method used. Conclusion The contents of total phenolics, amino acids and neutral sugar in stipes were higher than those in caps of shiitake, which suggested that stipes were more nutritional than caps in some respects. Hot air drying at 50 °C resulted in high total phenolic, amino acid, uronic acid and neutral sugar contents and antioxidant activities, which could be useful for the application of shiitake and related products in the food industry. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: The liquid chromatography–electrospray ionization-tandem mass spectrometer (LC–MS/MS) method coupled with an automated solid-phase extraction procedure has been developed to identify 22 psychiatric pharmaceuticals, including seven anxiolytic-sedative-hypnotics, six antidepressants, and nine anti-schizophrenia drugs, in wastewater samples from two psychiatric hospital wastewater treatment plants (P-WWTPs) and three municipal wastewater treatment plants (M-WWTPs) in Beijing, China. Analyte recoveries from spiking experiments in the WWTP influent and effluent at three concentrations ranged from 70% to 110%, excluding sulpiride, ziprasidone, and olanzapine. Method detection limits for five, eight, and nine analytes in the WWTP influent and effluent were 20–80, 1–16, and <1ngL−1, respectively. High psychiatric pharmaceutical concentrations (e.g., ∼942ngL−1oxazepam, 5552–12,782ngL−1 clozapine, 2762–9832ngL−1sulpiride, and 2030–4967ngL−1quetiapine) were frequently observed in P-WWTP influent compared to M-WWTPs. Although P-WWTPs typically had higher removal rates, significantly higher concentrations of the target compounds were observed in the P-WWTP secondary effluent than in the M-WWTP influent (e.g., ∼752ngL−1oxazepam, ∼8183ngL−1 clozapine, ∼10,833ngL−1sulpiride, and ∼1168ngL−1quetiapine). Thus, the discharge control of psychiatric pharmaceuticals from psychiatric hospitals requires improvement. [Copyright &y& Elsevier]

Abstract: A rapid resolution liquid chromatography (RRLC) method was developed for the simultaneous determination of 23 amino acids in rat serum after pre-column derivatization with 2,4-dinitrofluorobenzene (DNFB). The amino acid derivatives were separated on an Agilent Zorbax Eclipse Plus C18 (4.6mm×50mm, 1.8μm) column at 45°C. Ultraviolet (UV) detection was set at 360nm. Good separation of 23 amino acids was achieved within 10min with a ternary gradient elution of mobile phase at a flow rate of 1.5mLmin−1. Calibration curves were linear over the range from 1 to 500μmolL−1 with coefficients 0.9962 or better for each amino acid. The lower limits of quantification (LLOQ) of all 23 amino acids were 1μmolL−1 with signal-to-noise (S/N) ratio ≥4. Intra- and Inter-day precisions, expressed as relative standard deviation (RSD) percentages, were ranged from 0.32% to 3.09% and 0.67% to 5.82%, respectively. Finally, it was successfully applied to the determination of amino acids in rat serum with recoveries ranged from 90.8% to 106.0% and RSD percentages ranged from 1.78% to 4.68%, respectively. The results showed that the proposed method provided a shorter elution time, better resolution and sharper peak shapes for all amino acids. Compared with the conventional high performance liquid chromatography (HPLC) methods, even some ultra-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS), the established RRLC method was superior performance. [Copyright &y& Elsevier]

Abstract: The mixed sulfated/methacryloyl polysaccharide derivative was prepared and successfully immobilized onto the surface of porous silica particles by polymerization. Polysaccharide derivative was calculated as 10.33% in the stationary phase prepared. The new stationary phase (PMSP) showed both hydrophilic interaction (HILIC) and per aqueous liquid chromatography (PALC) characteristics. The effects of column temperature, the water content, pH and ion strength of mobile phase on the retention time of test compounds in highly aqueous eluents were investigated to evaluate the PALC features of PMSP. The column efficiency is about 31,000plates/m for benzoic acid in water/ACN (97/3, v/v) mobile phase at a flow rate of 1.0mL/min. Compared with C18 column, the PMSP had shorter retention time for weak polar and non-polar compounds, but also showed stronger retention for strong polar compounds. It indicated that PALC was a suitable mode of chromatography as replacement of HILIC and complementarity of reversed-phase liquid chromatography (RPLC). [Copyright &y& Elsevier]

Abstract: A novel molecularly imprinted polymer was synthesized with attapulgite employed as matrix, which is simple and time-saving. In this method, sudan I was chosen as template molecule, 2-vinylpyridine as functional monomer and ethylene glycol dimethacrylate as cross-linking agent, respectively. The imprinted polymer was characterized by the infrared spectroscopy and transmission electron microscopy. Then the selectivity experiments were performed on sudan dyes and the recognition coefficients for sudan I, sudan II, sudan III and sudan IV were 2.9, 1.9, 1.9 and 2.3, respectively. As the packing material of solid-phase extraction, the imprinted polymer has been applied to on-line concentration of the four sudan dyes in samples from Yellow River water, tomato sauce and sausage. The corresponding analytical methods to determine these sudan dyes have been developed. The limits of detection for these sudan dyes were in the range of 0.01–0.05ngmL−1 for Yellow River water, 1.0–3.0ngg−1 for tomato sauce and 0.8–3.0ngg−1 for sausage. [ABSTRACT FROM AUTHOR]

Abstract: Tetrandrine (TET) and fangchinoline (FAN) are basic and highly hydrophobic drugs with log P >5.7. In this work, a simple, inexpensive and efficient liquid-phase microextraction (LPME) technology combined with high-performance liquid chromatography (HPLC) was developed for the simultaneous analysis of tetrandrine and fangchinoline in plasma samples. Tetrahydropalmatine was used as internal standard. Several parameters influencing the efficiency of LPME were investigated and optimized including organic solvent, stirring rate, extraction time, salt concentration, organic modifier and pH. Under the optimal conditions, extraction recoveries from plasma samples were 46% for tetrandrine and 50% for fangchinoline, corresponding to the drugs enriched by a factor of 23 and 25 by LPME, respectively. Excellent sample clean-up was observed and good linearities with correlation coefficients (r) of 0.9979 (FAN) and 0.9995 (TET) were obtained in the range of 15–1000ngmL−1. The limits of detection (LOD, S/N=3) were 3.0ngmL−1 for FAN and 2.0ngmL−1 for TET. [Copyright &y& Elsevier]