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1.
Crit Rev Food Sci Nutr ; : 1-24, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36999956

RESUMO

With the high incidence of chronic diseases, precise nutrition is a safe and efficient nutritional intervention method to improve human health. Food functional ingredients are an important material base for precision nutrition, which have been researched for their application in preventing diseases and improving health. However, their poor solubility, stability, and bad absorption largely limit their effect on nutritional intervention. The establishment of a stable targeted delivery system is helpful to enhance their bioavailability, realize the controlled release of functional ingredients at the targeted action sites in vivo, and provide nutritional intervention approaches and methods for precise nutrition. In this review, we summarized recent studies about the types of targeted delivery systems for the delivery of functional ingredients and their digestion fate in the gastrointestinal tract, including emulsion-based delivery systems and polymer-based delivery systems. The building materials, structure, size and charge of the particles in these delivery systems were manipulated to fabricate targeted carriers. Finally, the targeted delivery systems for food functional ingredients have gained some achievements in nutritional intervention for inflammatory bowel disease (IBD), liver disease, obesity, and cancer. These findings will help in designing fine targeted delivery systems, and achieving precise nutritional intervention for food functional ingredients on human health.

2.
Molecules ; 27(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36296452

RESUMO

A series of novel indole Schiff base derivatives (2a-2t) containing a 1,3,4-thiadiazole scaffold modified with a thioether group were synthesized, and their structures were confirmed using FT-IR, 1H NMR, 13C NMR, and HR-MS. In addition, the antifungal activity of synthesized indole derivatives was investigated against Fusarium graminearum (F. graminearum), Fusarium oxysporum (F. oxysporum), Fusariummoniliforme (F.moniliforme), Curvularia lunata (C. lunata), and Phytophthora parasitica var. nicotiana (P. p. var. nicotianae) using the mycelium growth rate method. Among the synthesized indole derivatives, compound 2j showed the highest inhibition rates of 100%, 95.7%, 89%, and 76.5% at a concentration of 500 µg/mL against F. graminearum, F. oxysporum, F.moniliforme, and P. p. var. nicotianae, respectively. Similarly, compounds 2j and 2q exhibited higher inhibition rates of 81.9% and 83.7% at a concentration of 500 µg/mL against C. lunata. In addition, compound 2j has been recognized as a potential compound for further investigation in the field of fungicides.


Assuntos
Fungicidas Industriais , Fusarium , Antifúngicos/química , Fungicidas Industriais/química , Bases de Schiff/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Indóis/farmacologia , Sulfetos
3.
BMC Complement Altern Med ; 16(1): 495, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27905920

RESUMO

BACKGROUND: Potentilla fruticosa, also called "Jinlaomei" and "Gesanghua", is widely used as folk herbs in traditional Tibetan medicine in China to treat inflammations, wounds, certain forms of cancer, diarrhoea, diabetes and other ailments. Previous research found P. fruticosa leaf extract (C-3) combined with Ginkgo biloba extracts (EGb) showed obvious synergistic effects in a variety of oxidation systems. The aim of the present study was to further confirm the synergy of P. fruticosa combined with EGb viewed from physiological bioavailability and explore the related bioactive mechanism behind the synergism. METHODS: The microbial test system (MTS) was adopted to evaluate the related bioactive mechanism. The synergistic effects were evaluated by isobolographic analysis. The H2O2 production rate and antioxidant enzyme (Catalase (CAT), Peroxidase (POD), Superoxide dismutase (SOD), Glutathione peroxidase (GSH-PX)) activities were determined by the colorimetric method. Enzyme gene (CAT, SOD) expression was measured by real time-PCR. RESULTS: The MTS antioxidant activity results showed the combination of C-3 + EGb exhibited synergistic effects especially at the ratio 5:1. Components of isorhamnetin and caffeic acid in C-3 and EGb displayed strong antioxidant activities on MTS and their combination also showed significant synergy in promoting H2O2 production. The combinations of C-3 + EGb and isorhamnetin + caffeic acid promoted CAT and SOD enzyme activities and the ratio 1:1 exhibited the strongest synergy while no obvious promotion on POD and GSH-PX enzyme activities was found. Both combinations above promoted gene expression of CAT and SOD enzymes and the ratio 1:1 exhibited the strongest synergy. CONCLUSIONS: Antioxidant activity results in MTS further confirmed the significant synergy of C-3 combined with EGb and isorhamnetin combined with caffeic acid. The synergy of C-3 combined with EGb may be attributed to the combination of isorhamnetin + caffeic acid, which promoted CAT and SOD enzyme gene expression and further promoted the enzyme activities in E. coli. This study could further provide rational basis for optimizing the physiological bioavailability of P. fruticosa by using natural and safe antioxidants in low doses to produce new medicines and functional products.


Assuntos
Antioxidantes/farmacologia , Ginkgo biloba/química , Extratos Vegetais/farmacologia , Potentilla/química , Antioxidantes/uso terapêutico , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Peróxido de Hidrogênio/metabolismo , Testes de Sensibilidade Microbiana
4.
J Sep Sci ; 38(8): 1310-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25683560

RESUMO

A novel fully automated method based on dual column switching using turbulent flow chromatography followed by liquid chromatography with tandem mass spectrometry was developed for the determination of aflatoxin B1 , B2 , G1 , and G2 in corn powder, edible oil, peanut butter, and soy sauce samples. After ultrasound-assisted extraction, samples were directly injected to the chromatographic system and the analytes were concentrated into the clean-up loading column. Through purge switching, the analytes were transferred to the analytical column for subsequent detection by mass spectrometry. Different types of TurboFlow(TM) columns, transfer flow rate, transfer time were optimized. The limits of detection and quantification of this method ranged between 0.2-2.0 and 0.5-4.0 µg/kg for aflatoxins in different matrixes, respectively. Recoveries of aflatoxins were in range of 83-108.1% for all samples, matrix effects were in range of 34.1-104.7%. The developed method has been successfully applied in the analysis of aflatoxin B1 , B2 , G1 , and G2 in real samples.


Assuntos
Aflatoxinas/análise , Arachis/química , Óleos de Plantas/análise , Alimentos de Soja/análise , Zea mays/química , Aflatoxina B1/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Limite de Detecção , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Ultrassom
5.
J Sep Sci ; 36(20): 3379-86, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23939876

RESUMO

A novel design for a rapid clean-up method was developed for the analysis of pesticide residues in fruit and vegetables followed by LC-ESI-MS/MS. The acetonitrile-based sample extraction technique was used to obtain the extracts, and further clean-up was carried out by applying the streamlined procedure on a multiplug filtration clean-up column coupled with a syringe. The sorbent used for clean-up in this research is multiwalled carbon nanotubes, which was mixed with anhydrous magnesium sulfate to remove water from the extracts. This method was validated on 40 representative pesticides and apple, cabbage, and potato sample matrices spiked at two concentration levels of 10 and 100 µg/kg. It exhibited recoveries between 71 and 117% for most pesticides with RSDs < 15%. Matrix-matched calibrations were performed with the coefficients of determination >0.995 for most studied pesticides between concentration levels of 10-500 µg/L. The LOQs for 40 pesticides ranged from 2 to 50 µg/kg. The developed method was successfully applied to the determination of pesticide residues in market fruit and vegetable samples.


Assuntos
Filtração/métodos , Frutas/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Verduras/química , Filtração/instrumentação , Contaminação de Alimentos/análise , Nanotubos de Carbono/química
6.
Molecules ; 18(10): 11964-77, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24077175

RESUMO

An efficient synthesis of 2-hydroxy-2-(trifluoromethyl)-2H-chromene-3-carboxylates was carried out under solvent-free conditions in an oven or microwave oven via the Knoevenagel condensation of salicylaldehydes with ethyl trifluoroacetoacetate followed by intramolecular cyclization in the presence of silica-immobilized L-proline. The structures of the title compounds were characterized by IR, ¹H-NMR, ¹³C-NMR, HRMS and X-ray single crystal diffraction. The improved method described herein is economical, easily-operated and environmentally friendly. Furthermore, the catalyst can be recovered conveniently and reused without obvious loss of activity.


Assuntos
Benzopiranos/síntese química , Prolina/química , Dióxido de Silício/química , Aldeídos/química , Catálise , Cristalografia por Raios X , Fluoracetatos/química , Química Verde , Modelos Moleculares , Conformação Molecular , Técnicas de Síntese em Fase Sólida , Solventes/química
7.
Environ Monit Assess ; 185(11): 9101-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23649477

RESUMO

A modified LC-MS method for the analysis of mepiquat residue in wheat, potato, and soil was developed and validated. A hydrophilic interaction liquid chromatographic column has been successfully used to retain and separate the mepiquat. Mepiquat residue dynamics and final residues in supervised field trials at Good Agricultural Practice (GAP) conditions in wheat, potato, and soil were studied. The limits of quantification for mepiquat in all samples were all 0.007 mg kg(-1), which were lower than their maximum residue limits. At fortification levels of 0.04, 0.2, and 2 mg kg(-1) in all samples, recoveries ranged from 77.5 to 116.4% with relative standard deviations of 0.4-7.9% (n = 5). The dissipation half-lives (T 1/2) of mepiquat in soil (wheat), wheat plants, soil (potato), and potato plants were 4.5-6.3, 3.0-5.6, 2.2-4.6, and 2.4-3.2 days, respectively. The final residues of mepiquat were below 0.153 mg kg(-1) in soil (wheat), 0.052-1.900 mg kg(-1) in wheat, below 0.072 mg kg(-1) in soil (potato), and below 1.173 mg kg(-1) in potato at harvest time. Moreover, pesticide risk assessment for all the detected residues was conducted. A maximum 0.0012% of acceptable daily intake (150 mg kg(-1)) for national estimated daily intake indicated low dietary risk of these products.


Assuntos
Resíduos de Praguicidas/análise , Piperidinas/análise , Reguladores de Crescimento de Plantas/análise , Poluentes do Solo/análise , Monitoramento Ambiental , Meia-Vida , Solo/química , Solanum tuberosum/química , Triticum/química
8.
Environ Monit Assess ; 185(12): 9743-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23793538

RESUMO

The dissipation and residues of bispyribac-sodium in rice cropping system were studied. Bispyribac-sodium residues were extracted by a simple analytical method based on QuEChERs and detected by LC-MS/MS. The limit of detection for bispyribac-sodium of this method was 0.375 × 10(-3) ng. The limit of quantification (LOQ) was 5.0 µg/kg for rice plant samples, 2.0 µg/kg for rice hull, 0.2 µg/kg for water, and 0.1 µg/kg for soil and husked rice samples. The average recoveries of bispyribac-sodium ranged from 74.7 to 108%, with relative standard deviations less than 13%. The half-lives of bispyribac-sodium in rice plant, water, and soil were in the range of 1.4-5.6 days. More than 90% of bispyribac-sodium residue dissipated within 5 days. The final residues of bispyribac-sodium in rice were all below LOQ at harvest time.


Assuntos
Benzoatos/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Herbicidas/análise , Oryza/química , Resíduos de Praguicidas/análise , Pirimidinas/análise , Benzoatos/química , Poluentes Ambientais/química , Meia-Vida , Herbicidas/química , Resíduos de Praguicidas/química , Pirimidinas/química , Solo/química
9.
Bull Environ Contam Toxicol ; 90(4): 499-503, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23277368

RESUMO

Uniconazole residue dynamics and final residues in supervised field trials at GAP conditions were studied. The residue levels and dissipation rate of uniconazole was detected by LC-MS. At fortification levels of 0.04, 0.2 and 2 mg kg(-1), recoveries ranged from 78.7 % to 100.9 % with RSDs of 0.1 %-4.6 % (n = 5). The dissipation experiments showed the half-lives (T1/2) of uniconazole in soil and wheat plants were 2.9-3.3 and 3.8-4.4 days, respectively. At pre-harvest intervals (PHI) of 45 and 60 days, uniconazole residue were no detectable or below the limit of quantification (LOQ) in soil, wheat plants and wheat.


Assuntos
Poluentes Ambientais/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Reguladores de Crescimento de Plantas/análise , Solo/química , Triazóis/análise , Triticum/metabolismo , Poluentes Ambientais/química , Poluentes Ambientais/metabolismo , Contaminação de Alimentos , Meia-Vida , Resíduos de Praguicidas/química , Resíduos de Praguicidas/metabolismo , Praguicidas/química , Praguicidas/metabolismo , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/metabolismo , Triazóis/química , Triazóis/metabolismo
10.
Bull Environ Contam Toxicol ; 90(4): 477-81, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23242258

RESUMO

To select representative crop among leaf vegetables which may contain the highest residue after fungicide uses, open field applications with thiophanate-methyl on six crops including pakchoi, rape, crown daisy, amaranth, spinach and lettuce were designed and conducted. In this study, a high-performance liquid chromatography and electrospray ionization-tandem mass spectrometry with selected reaction monitoring was used to simultaneously determine thiophanate methyl and its metabolite carbendazim residue in various samples. The limit of quantification for thiophanate methyl and carbendazim were established in the range of 0.005-0.01 mg kg(-1) for all samples. It was shown that recoveries ranged from 67.8 % to 102.3 % for thiophanate methyl, and 72.0 %-112.6 % for carbendazim at spiked levels of 0.01-0.1 mg kg(-1). It's found that thiophanate methyl converts to carbendazim very quickly. In supervised field trials, the half-lives of thiophanate methyl in six leaf vegetables were in the range of 1.26-2.65 days, and the half-lives of carbendazim were in the range of 2.53-4.28 days. It was also found that thiophanate methyl residue in spinach and amaranth was higher than others after application. It's recommended that spinach or amaranth can be selected as representative crop in leaf vegetables in study of systemic fungicides with similarity as thiophanate methyl.


Assuntos
Benzimidazóis/metabolismo , Carbamatos/metabolismo , Fungicidas Industriais/metabolismo , Resíduos de Praguicidas/metabolismo , Tiofanato/metabolismo , Verduras/metabolismo , Amaranthus/metabolismo , Benzimidazóis/química , Brassica napus/metabolismo , Brassica rapa/metabolismo , Carbamatos/química , Chrysanthemum/metabolismo , Fungicidas Industriais/química , Lactuca/metabolismo , Resíduos de Praguicidas/química , Especificidade da Espécie , Spinacia oleracea/metabolismo , Tiofanato/química
11.
Front Nutr ; 9: 879518, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35938118

RESUMO

A multi-residue method has been developed for the identification and quantification of 103 common veterinary drug residues in milk and dairy Products. This method was based on QuEChERS with dispersive solid-phase where C18 sorbent and anhydrous sodium sulfate were used to sample purification. After evaporation and reconstitution, the samples were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. The mean recovery results were all higher than 60% except ampicillin, pipemidic acid, enoxacin, and estriol, and the relative standard deviation was <20.0%. The limit of quantification ranged between 0.1 and 5 µg/kg for milk and between 0.5 and 25 µg/kg for milk powder. It was successfully used to detect residues of veterinary drug in real samples. This study proposes a simple and fast analytical method for monitoring multi-class veterinary drug residues to ensure food safety.

12.
Front Nutr ; 9: 949025, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903452

RESUMO

A method for simultaneous determination of 22 polycyclic aromatic hydrocarbons (PAHs) residues in vegetable oils by gas chromatography-electrostatic field orbitrap high resolution mass spectrometry (Orbitrap GC-MS) was established. The samples were vortexed with acetonitrile, centrifuged at 8,000 r/min for 5 min, and frozen at -70°C for 10 min. The extracts of upper layer were poured out, dried with nitrogen at 40°C, redissolved in dichloromethane, and measured by Orbitrap GC-MS. The matrix interference in vegetable oil could be effectively removed by determining the accurate mass number of target compounds under the full scan mode. Six typical vegetable oil samples (soybean oil, sesame oil, peanut oil, olive oil, rapeseed oil, sunflower oil) were used for method validation. The calibration curve displayed good linearity in the range of 1-100 ng/mL, with correlation coefficients > 0.9950. The limits of detection (LODs) were in the range of 0.10-0.60 µg/kg, and the limits of quantification (LOQs) were in the range of 0.35-2.00 µg/kg. The average spiked recoveries of 22 PAHs in 6 matrices at 5, 50 and 100 µg/kg levels were 76.4-115.4%, and the average relative standard deviations (RSDs) were 1.8-10.8%. The results showed that 22 PAHs were detected in 6 types of 90 edible vegetable oil samples in the Chinese market by this method. Meanwhile, the abundance of light PAHs (LPAHs) was higher than that of heavy PAHs (HPAHs), and its relative contribution of LPAHs to the total PAHs was higher. All levels of BaP conformed to the Chinese requirement of upper limit, 10 µg/kg. However, 13.3 and 11.1% of the samples exceeded the maximum limits of BaP and PAH4 set by EU, 2 and 10 µg/kg, respectively. The total concentrations of 22 PAHs (defined as PAH22) varies greatly among different oil species, and the average PAH22 contents were listed in descending order as follows: peanut oil > sesame oil > olive oil > rapeseed oil > soybean oil > sunflower seed oil. The established method effectively avoided interference from large amounts of lipids and pigments. Therefore, the method is simple, sensitive and suitable for rapid screening and confirmation of PAHs in vegetable oil.

13.
J Anal Methods Chem ; 2022: 7684432, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757318

RESUMO

To analyze pesticide residues, GC coupled with quadrupole-Orbitrap MS (GC-Orbitrap-MS) has become a powerful tool because of its unique characteristics of accurate mass full-spectrum acquisition, high resolution, fast acquisition rates, and overcoming matrix interference. This paper presents an efficiency evaluation of GC-Orbitrap-MS for identification and quantitation in the 352 pesticide residues analysis of chrysanthemum flowers in full-scan mode. A streamlined pretreatment approach using one-step extraction and dilution was used, which provided high-throughput processing and excellent recovery. The samples were extracted using acetonitrile. The extracted solution was purified by a Sin-QuEChERS Nano column to suppress the matrix in chrysanthemum flowers and determined by GC-Orbitrap-MS. The calibration curves for the 352 pesticides obtained by GC-Orbitrap-MS were linear in the range of 0.5-200 µg·kg-1, with the correlation coefficients higher than 0.99. The limits of detection (LODs) and the limits of quantification (LOQs) for the 352 pesticide residues were 0.3-3.0 µg·kg-1 and 1.0-10.0 µg·kg-1, respectively. The average recoveries in chrysanthemum flower at three levels were 95.2%, 88.6%, and 95.7%, respectively, with relative standard deviations (RSDs) of 7.1%, 7.5%, and 7.2%, respectively. Lastly, the validated method and retrospective analysis was applied to a total of 200 chrysanthemum flower samples bought in local pharmacies. The proposed method can simultaneously detect multipesticide residues with a good performance in qualitative and quantitative detection.

14.
Front Nutr ; 9: 848294, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35308292

RESUMO

A UPLC-MS/MS method was developed for the detection of tropomyosin (TM) in shrimp and crab. After simple extraction, the samples were purified by immunoaffinity column and then digested by trypsin. The obtained sample was separated by Easy-nLC 1000-Q Exactive. The obtained spectrums were analyzed by Thermo Proteome Discoverer 1.4 software and then ANIQLVEK with high sensitivity was selected as the quantitative signature peptide. Isotope-labeled internal standard was used in the quantitative analysis. The method showed good linearity in the range of 5-5,000 µg/L with a limit of quantification (LOQ) of 0.1 mg/kg. The average recoveries were 77.22-95.66% with RSDs ≤ 9.97%, and the matrix effects were between 88.53 and 112.60%. This method could be used for rapid screening and quantitative analysis of TM in shrimp and crab. Thus, it could provide technical support for self-testing of TM by food manufacturers and promote further improvement of allergen labeling in China.

15.
Int J Anal Chem ; 2022: 4372295, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204714

RESUMO

A new method was developed for the identification and determination of L-ergothioneine in cosmetics based on ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The pretreatment method, chromatographic column, chromatographic conditions, and mass spectrometric conditions of cosmetic samples were optimized. Methanol was chosen as the extraction solvent, 85% acetonitrile with 0.1% FA was selected as the mobile phase, and the Waters CORTECS UPLC hydrophilic interaction liquid chromatography (HILIC) column was chosen for the separation. The sample was extracted with methanol and filtered, then separated by HILIC and detected by triple-quadrupole mass spectrometry. The quantitation was done under the matrix calibration curve using the external standard method. The results showed good linear relationships in the range of 5-200 ng/mL, and the correlation coefficient was greater than 0.999 in cosmetic samples. The limit of detection was in the range of 25-50 µg/kg and the limit of quantitation was in the range of 50-100 µg/kg. The recoveries of the method spiked ranged from 85.3% to 96.2% and the relative standard deviation (RSD) was in the range of 0.84%-2.08% (n = 6). The method is simple, quick, and accurate for the determination of L-ergothioneine in cosmetics, and has great practical value.

16.
Acta Pharm Sin B ; 12(2): 890-906, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35256953

RESUMO

Antrodia cinnamomea is extensively used as a traditional medicine to prevention and treatment of liver cancer. However, its comprehensive chemical fingerprint is uncertain, and the mechanisms, especially the potential therapeutic target for anti-hepatocellular carcinoma (HCC) are still unclear. Using UPLC‒Q-TOF/MS, 139 chemical components were identified in A. cinnamomea dropping pills (ACDPs). Based on these chemical components, network pharmacology demonstrated that the targets of active components were significantly enriched in the pathways in cancer, which were closely related with cell proliferation regulation. Next, HCC data was downloaded from Gene Expression Omnibus database (GEO). The Cancer Genome Atlas (TCGA) and DisGeNET were analyzed by bioinformatics, and 79 biomarkers were obtained. Furtherly, nine targets of ACDP active components were revealed, and they were significantly enriched in PI3K/AKT and cell cycle signaling pathways. The affinity between these targets and their corresponding active ingredients was predicted by molecular docking. Finally, in vivo and in vitro experiments showed that ACDPs could reduce the activity of PI3K/AKT signaling pathway and downregulate the expression of cell cycle-related proteins, contributing to the decreased growth of liver cancer. Altogether, PI3K/AKT-cell cycle appears as the significant central node in anti-liver cancer of A. Cinnamomea.

17.
J Sep Sci ; 34(6): 640-50, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21312330

RESUMO

In the experiment, a high-performance liquid chromatography and electrospray ionization-tandem mass spectrometry with selected reaction monitoring was used to simultaneously determine various classes of phytohormones, including indole-3-acetic acid, α-naphthaleneacetic acid, 2-chlorobenzoic acid, 4-chlorobenzoic acid, indole-3-butyric acid, gibberellic acid, 2,4-dichlorophenoxyacetic acid, 2-naphthoxyacetic acid, abscisic acid, 2,3,5-triiodobenzoic acid, uniconazole, paclobutrazol and 2,4-epibassinolide in rape tissues. The analyses were separated by an HPLC equipped with a reversed-phase column using a binary solvent system composed of methanol and water, both containing 0.1% of formic acid. The matrix effect was also considered and determined. The technology was applied to analyze rape tissues, including roots, stems, leaves, flowers, immature pods and rape seeds. The rape tissues were subjected to ultrasound-assisted extraction and purified by dispersive solid-phase extraction, and then transferred into the liquid chromatography system. The detection limit for each plant hormone was defined by the ratio of signal/background noise (S/N) of 3. The results showed perfect linearity (R(2) values of 0.9987-1.0000) and reproducibility of elution times (relative standard deviations, RSDs,<1%) and peak areas (RSDs,<7%) for all target compounds.


Assuntos
Brassica rapa/química , Cromatografia Líquida/métodos , Extratos Vegetais/análise , Reguladores de Crescimento de Plantas/análise , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida/instrumentação , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
18.
Anal Methods ; 13(10): 1278-1285, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33624658

RESUMO

In the present study, an antibody against phenylethanolamine A (PEA) was produced, confirmed, and used in a surface plasmon resonance (SPR)-based measurement. Bovine serum albumin (BSA)-conjugated PEA was linked to nano-gold particles bound to l-cysteine modified on the surface of a Au-NP sensor chip. The concentrations of antigen and antibody were optimized, and the designed biosensor chip was investigated to examine the stability and accuracy of the proposed method. The recovery of PEA ranged from 80.4-93.4% in swine urine samples with spike levels of 5, 10 and 20 ng mL-1, and the relative standard deviations of PEA were less than 2%. PEA analogues, such as clenbuterol, ractopamine, and salbutamol, did not influence the PEA measurement. The developed method could be used to measure PEA in swine urine samples.


Assuntos
2-Hidroxifenetilamina , Técnicas Biossensoriais , 2-Hidroxifenetilamina/análogos & derivados , Animais , Ouro , Ressonância de Plasmônio de Superfície , Suínos
19.
Front Nutr ; 8: 767801, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34957181

RESUMO

The purpose of this research was to develop a simple, sensitive, and accurate method for simultaneous determination of 35 free amino acids using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). Tea samples were extracted with boiling water bath, and then separated by XBridge BEH Amide column by gradient elution. The exact mass and MS/MS spectra of the target compound was detected under the TOF-MS and Information dependent acquisition (IDA)-MS/MS mode. The results demonstrated good linearity (R 2 > 0.9980) in the range of 0.5-1,000 ng/mL. The limits of detection (LODs) were 0.13-25.00 mg/kg and the limits of quantitation (LOQs) were 0.25-50.00 mg/kg. The recovery rate ranged from 70.1 to 105.1% with relative standard deviations (RSDs) <11% (n = 6). This research provides a targeted strategy for developing an analysis method for amino acids in tea.

20.
Foods ; 10(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34359521

RESUMO

A new method for screening pesticide residues in vegetable and fruit juices by the multi-plug filtration cleanup (m-PFC) method combined with gas chromatography-electrostatic field orbitrap high resolution mass spectrometry(GC-Orbitrap/MS) was developed. The samples were extracted with acetonitrile, purified with m-PFC and determined by GC-Orbitrap/MS. Qualitative analysis was confirmed by retention time, accurate molecular mass and quantitative analysis were performed with the matrix standard calibration. It could eliminate matrix interference effectively. Eight kinds of typical samples (orange juice, apple juice, grape juice, strawberry juice, celery juice, carrot juice, cucumber juice, tomato juice) were evaluated. The linear ranges of the 350 pesticides were from 5 to 500 µg/kg, with good correlation coefficients greater than 0.990. The limits of detection (LODs) were 0.3-3.0 µg/kg and the limits of quantification (LOQs) were 1.0-10.0 µg/kg. The average recoveries at three spiked levels of 10, 100, 200 µg/kg were in the range of 72.8-122.4%, with relative standard deviations (RSDs) of 2.0-10.8%. The method has effectively improved the determination efficiency of pesticide residue screening by high-resolution mass spectrometry in vegetable and fruit juices.

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