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1.
Fa Yi Xue Za Zhi ; 35(4): 411-418, 2019 Aug.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-31532148

RESUMO

Abstract: Objective To establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) rapid determination method for simultaneous analysis of 20 fentanyl-related substances in blood. Methods With fentanyl-D5 as an internal standard, the blood was extracted by liquid-liquid extraction (LLE), then separated with an ACQUITY UPLC HSS T3 chromatographic column, and finally 20 fentanyl-related substances were simultaneously analyzed with multiple reaction monitoring (MRM) mode. Results The limits of detection (LOD) of all compounds were 0.02-0.03 ng/mL, and the limits of quantitation (LOQ) were 0.05-0.2 ng/mL. Within the mass concentration range of 0.05-40 ng/mL, 20 fentanyl-related substances had a good linear relationship, and correlation coefficients were larger than 0.99. The accuracy of the method was 87.69%-114.68% and the extraction recovery rate was 85.35%-101.80%, and no significant matrix effect was observed. The established method was successfully applied to the detection of sufentanil in rat blood after sufentanil was injected. Sufentanil could still be detected in blood of rats 10 h after sufentanil injection. Conclusion The established method has the advantages of simple pretreatment, high sensitivity and good selectivity, and can be used for the determination of fentanyl-related substances in forensic toxicology analysis.


Assuntos
Cromatografia Líquida de Alta Pressão , Fentanila/sangue , Espectrometria de Massas em Tandem , Animais , Toxicologia Forense , Ratos , Reprodutibilidade dos Testes , Sufentanil/sangue
2.
Fa Yi Xue Za Zhi ; 35(4): 419-422, 2019 Aug.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-31532149

RESUMO

Abstract: Objective To develop a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the determination of the content of 4-fluoromethamphetamine (4-FMA) in rat plasma, and to provide a methodological basis for the study of the toxicokinetics of 4-FMA in rats. Methods Rat plasma samples were added into internal standard methamphetamine (MA). Its proteins were precipitated with methanol and then separated with Poroshell 120 EC-C18 chromatographic column. A 0.1% formic acid aqueous solution and a 0.1% formic acid acetonitrile solution were used as the mobile phase at the flow rate of 0.4 mL/min. Electrospray ionization source was used for detection in the multiple reaction monitoring (MRM) mode. Results The linear relationship was good when the mass concentration of 4-FMA in plasma samples was in the range of 5-1 000 ng/mL (r>0.999). The limit of detection (LOD) was 3 ng/mL and the limit of quantification (LOQ) was 5 ng/mL. The accuracy was expressed as relative error (RE), and in the range of ±5%, the intra-day precision and inter-day precision (relative standard deviation, RSD) less than 9%, and the extraction recovery rate was more than 90%. The analysis and detection of plasma samples were completed within 2.5 min. Conclusion This study developed a HPLC-MS/MS method for the determination of 4-FMA in rat plasma samples. This method is accurate, rapid, simple and sensitive and can be applied to the study of toxicokinetics of 4-FMA.


Assuntos
Cromatografia Líquida de Alta Pressão , Metanfetamina/sangue , Espectrometria de Massas em Tandem , Animais , Limite de Detecção , Metanfetamina/análogos & derivados , Ratos , Reprodutibilidade dos Testes , Toxicocinética
3.
Sheng Wu Gong Cheng Xue Bao ; 35(9): 1771-1786, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31559758

RESUMO

Rv2742 is a novel gene identified from Mycobacterium tuberculosis H37Rv by the proteogenomics strategy. The aim of this study was to establish a system of soluble expression and purification of the missing protein Rv2742 in M. tuberculosis H37Rv, to provide reference for further research on the biological function of Rv2742. The soluble protein was not successfully induced by prokaryotic expression vectors pGEX-4T-2-Rv2742, pET-32a-Rv2742, pET-28a-Rv2742 and pMAL-c2X-Rv2742. After the codon of novel gene Rv2742 was optimized according to E. coli codon usage frequency, only the recombinant strain containing plasmid pMAL-c2X-Rv2742 could produce soluble products of Rv2742 encoding gene. In addition, the expression effects of the desired fusion protein were also analyzed under different conditions including hosts, culture temperatures and IPTG concentrations. The optimum expression conditions were as follows: Rosetta (DE3) host, 16 °C culture temperature and 0.5 mmol/L IPTG. After being purified by affinity chromatography with amylose resin, the fusion protein sequence was confirmed by LC-MS/MS. These results indicated that the novel gene Rv2742 product could be successfully induced and expressed in a soluble form by the expression system pMAL-c2X with MBP tag. Our findings provide reference for studies on potential interaction and immunogenicity.


Assuntos
Mycobacterium tuberculosis , Cromatografia Líquida , Clonagem Molecular , Escherichia coli , Mycobacterium tuberculosis/genética , Proteínas Recombinantes de Fusão , Espectrometria de Massas em Tandem
4.
J Agric Food Chem ; 67(37): 10423-10431, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31487168

RESUMO

Plants often produce antifungal peptides and proteins in response to infection. Also wheat, which is the main ingredient of bread dough, contains such components. Here, we show that while some industrial strains of the baker's yeast Saccharomyces cerevisiae can efficiently ferment dough, some other strains show much lower fermentation capacities because they are sensitive to a specific wheat protein. We purified and identified what turned out to be a thaumatin-like protein through a combination of activity-guided fractionation, cation exchange chromatography, reversed-phase HPLC, and LC-MS/MS. Recombinant expression of the corresponding gene and testing the activity confirmed the inhibitory activity of the protein.


Assuntos
Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Triticum/química , Cromatografia Líquida , Fermentação , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Espectrometria de Massas em Tandem , Triticum/genética , Triticum/metabolismo , Triticum/microbiologia
5.
J Agric Food Chem ; 67(38): 10800-10812, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31490681

RESUMO

In this work, a highly efficient pesticide residue screening and quantification method was established using ultrahigh-performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry based on in-source fragmentation. Over 400 pesticides were tested, among which 96 pesticides displayed in-source fragmentation. A novel concept of in-source fragment fraction was proposed to evaluate the extent of in-source fragmentation, which was found to be chemical structure- and source parameter-dependent. A high-resolution MS/MS library containing 403 pesticides and 126 fragments was created and was applied for library searching of pesticide residues in vegetables and fruits. The introduction of in-source fragments effectively circumvented misannotation and occurrence of false negatives. The quantification ability for the fragments was validated in terms of recovery, linearity, and limit of quantification and its superiority to the parent pesticides was established. Finally, the proposed method was applied for the analysis of real samples and proficiency test samples, and false negative results were successfully avoided in the analysis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Resíduos de Praguicidas/química , Espectrometria de Massas em Tandem/métodos , Verduras/química , Contaminação de Alimentos/análise , Limite de Detecção
6.
J Agric Food Chem ; 67(38): 10782-10790, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31490683

RESUMO

Systematic investigation of cyproconazole, including absolute stereochemistry, fungicidal activity, quantification in two matrixes, and stereoselective degradation in cucumber, are conducted in this study. By virtue of vibrational circular dichroism (VCD) spectroscopy, absolute configurations of four stereoisomers were identified to be (2R,3R)-(+)-, (2R,3S)-(+)-, (2S,3S)-(-)-, and (2S,3R)-(-)-cyproconazoles. Then four stereoisomers exhibited stereoselective fungicidal activities against Fusarium graminearum Schw and Magnaporthe oryzae, and the order of fungicidal activity was (2S,3S)-(-)-stereoisomer > the stereoisomer mixture > (2S,3R)-(-)-stereoisomer > (2R,3R)-(+)-stereoisomer > (2R,3S)-(+)-stereoisomer. Moreover, chiral liquid chromatography-tandem mass spectrometry was used to identify and quantify cyproconazole stereoisomers in soil and cucumber matrixes. Good linearity (R2 ≥ 0.99) and recoveries (86.79-92.47%, RSD ≤ 3.94%) for them were achieved, individually. Furthermore, stereoselective degradation of four cyproconazole stereoisomers was observed in cucumber and the order of degradation rate was (2R,3R)-(+)-cyproconazole > (2S,3S)-(-)-cyproconazole > (2R,3S)-(+)-cyproconazole > (2S,3R)-(-)-cyproconazole. We envision that such systematic assessments of chiral fungicides at an enantiomeric level would provide valuable information in future studies involving enantioselective physiological, metabolic, and toxicological activities.


Assuntos
Fungicidas Industriais/química , Triazóis/química , Alternaria/efeitos dos fármacos , Alternaria/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Cucumis sativus/química , Contaminação de Alimentos/análise , Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Rhizoctonia/efeitos dos fármacos , Rhizoctonia/crescimento & desenvolvimento , Poluentes do Solo/química , Poluentes do Solo/farmacologia , Estereoisomerismo , Espectrometria de Massas em Tandem , Triazóis/farmacologia
7.
J Agric Food Chem ; 67(38): 10791-10799, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31497956

RESUMO

Very weak signals of fragment ions of nosiheptide could be observed using liquid chromatography-tandem mass spectrometry. The preparation of 4-hydroxymethyl-3-methyl-1H-indole-2-carboxylic acid (HMIA), a specific fragment of nosiheptide, by alkaline hydrolysis is described. HMIA showed a good mass spectrometric signal in negative electrospray ionization mode. In the new method, the nosiheptide residue in muscle tissue was hydrolyzed with sodium hydroxide aqueous solution; this was followed by cleanup using mixed mode cartridges. Identification and quantification of nosiheptide were carried out by analyzing HMIA in hydrolysate of muscles. Nosiheptide showed a good linear relationship (r > 0.996) in the calibration range of 2-500 µg/kg, and a low limit of quantification of 2 µg/kg was obtained in swine, chicken, and fish muscles. Recoveries of nosiheptide from spiked muscle samples were 85-108% with relative standard deviations less than 10%. The proposed method was successfully applied for the detection of the nosiheptide residue in medicated animal tissues samples.


Assuntos
Antibacterianos/química , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/química , Contaminação de Alimentos/análise , Carne/análise , Espectrometria de Massas em Tandem/métodos , Álcalis/química , Animais , Galinhas , Peixes , Hidrólise , Limite de Detecção , Músculos/química , Suínos , Tiazóis/química
8.
Bioresour Technol ; 293: 122169, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31561980

RESUMO

Pseudomonas sp. C27 is a facultative autotrophic bacterium that can grow mixotrophically to undergo denitrifying sulfide removal (DSR) reactions with both organic matters and sulfide as electron donors. A detailed understanding of how the C27 strain simultaneously removes nitrogen, sulfur and carbon from water is critical for optimal DSR process design and implementation. This study is the first to reveal the pathways of nitrogen and sulfur metabolisms, identifying a total of 47 proteins that are related to the nitrogen metabolism and seven proteins to the sulfur metabolism of strain C27 using iTRAQ and LC-MS/MS techniques. The proposed pathway of nitrogen metabolism for strain C27 from external nitrate to nitrogen gas and phosphate with a coupled ammonia cycle is based on the identified proteins, and suggests that nitrate was not essential for nitrogen metabolism and could be replaced by nitrite as the sole nitrogen source for C27.


Assuntos
Nitrogênio , Pseudomonas , Cromatografia Líquida , Desnitrificação , Nitratos , Sulfetos , Enxofre , Espectrometria de Massas em Tandem
9.
Shokuhin Eiseigaku Zasshi ; 60(4): 108-112, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31474651

RESUMO

Assuming the intentional adulteration of beverages with plant toxins, an LC-MS/MS method for the simultaneous determination of 18 plant toxins (lycorine, galantamine, ricinine, scopolamine, gelsemine, atropine, colchicine, α-solanine, jervine, α-chaconine, veratramine, mesaconitine, digoxin, protoveratrine A, aconitine, hypaconitine, oleandrin, and digitoxin) was developed. As analytical samples, beer, distilled spirits, blend tea, ready-to-drink (RTD) coffee, and fermented milk drink were selected. The extraction and purification of the analytes were performed using modified QuEChERS method. Method validation in terms of intra-day precision, accuracy, and extraction recovery obtained satisfactory results. The calibration curves for the analytes were linear from 5 to 200 ng/mL (r>0.990), which enabled the determination of toxins in even trace amounts.


Assuntos
Bebidas/análise , Cromatografia Líquida , Análise de Alimentos/métodos , Espectrometria de Massas em Tandem , Toxinas Biológicas/análise
10.
Shokuhin Eiseigaku Zasshi ; 60(4): 96-107, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31474657

RESUMO

LC/Tribrid Orbitrap was developed to determine phosphodiesterase-5 (PDE-5) inhibitors and their analogs as adulterants in dietary supplements. High-resolution MS/MS and MS3 spectra of PDE-5 inhibitors and their analogs were obtained by LC/Tribrid Orbitrap using both higher-energy collisional dissociation and collision-induced dissociation. We investigated dietary supplements that claim to enhance men's sexual performance, and detected PDE-5 inhibitors and their analogs. We also estimated the structures of the PDE-5 inhibitor analogs and the impurities of PDE-5 inhibitors and their analogs in the dietary supplements.


Assuntos
Suplementos Nutricionais/análise , Inibidores da Fosfodiesterase 5/análise , Espectrometria de Massas em Tandem , Cromatografia Líquida , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5
11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 870-873, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31515778

RESUMO

OBJECTIVE: To assess the value of dry blood spot tandem mass spectrometry for the diagnosis of autism spectrum disorder (ASD). METHODS: Peripheral blood samples of 277 autistic children were collected. Their amino acid and carnitine profiles were detected by liquid chromatography tandem mass spectrometry. Urine samples of suspected patients were collected for verification by gas chromatography mass spectrometry. Blood samples were also taken for genetic testing. RESULTS: Of the 277 children with ASD, 19 (6.9%) were suspected to be with inborn error of metabolism (IEM), which included 6 cases with amino acidemia, 9 with organic acidemia and 4 with fatty acidemia. Three cases of phenylketonuria, one case of homocysteinemia, one case of propionemia, one case of methylmalonic acidemia, one case of glutaric acidemia, one case of isovaleric acidemia, one case of argininemia, one case of citrullinemia I and four cases of primary carnitine deficiency were confirmed by genetic testing, which yielded an overall diagnostic rate of 5.1% (14/277). CONCLUSION: Our result has provided further evidence for the co-occurrence of ASD and IEM. Tandem mass spectrometry has a great value for the diagnosis and treatment of ASD in childhood.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Transtorno do Espectro Autista/complicações , Criança , Teste em Amostras de Sangue Seco , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Erros Inatos do Metabolismo/complicações , Espectrometria de Massas em Tandem
12.
Bioresour Technol ; 291: 121853, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377510

RESUMO

The concentration of antibiotics in anaerobically digested swine wastewater (ADSW) usually gradually increases due to the addition of antibiotics in livestock feed. Lemna aequinoctialis was used to treatment synthetic ADSW contaminated by oxytetracycline (OTC) whose concentrations were 0.05, 0.25, 0.50 and 1.00 mg/L, and its influences on NH3-N and TP remove were investigated. The fresh weight, photosynthetic pigment and protein content of duckweed were also investigated. Results have shown that nutrient removal and duckweed growth followed the "dose-response" relationships, and 0.05 mg/L OTC could significantly promote the synthesis of photosynthetic pigments and proteins in duckweed. Meanwhile, the protein content gradually decreased during investigation. More important, the degradation products and possible degradation pathways of OTC were diagrammatized via liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), and twelve intermediates were detected in the duckweed systems. This study can offer a novel view for phytoremediation of ADSW containing antibiotics by aquatic plants.


Assuntos
Antibacterianos/metabolismo , Araceae/metabolismo , Nutrientes , Oxitetraciclina/metabolismo , Águas Residuárias/química , Anaerobiose , Animais , Biodegradação Ambiental , Cromatografia Líquida , Suínos , Espectrometria de Massas em Tandem
13.
Medicine (Baltimore) ; 98(33): e16827, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31415401

RESUMO

INTRODUCTION: Ornithine transcarbamylase deficiency (OTCD) is a common metabolic disease of urea circulation disorder. We reported the clinical, brain imaging and genetic characteristics of 2 cases with OTCD. The patients' clinical features, novel gene mutations, cranial MR specific imaging changes and blood tandem mass spectrometry, and urine gas chromatography-mass spectrometry were, retrospectively, analyzed. PATIENT CONCERNS: Patient 1 was a 1.6-year-old female. She was admitted to the hospital with 2-months history of general irritability and disturbance of consciousness for a day. Patient 2 was a 3.7-year-old female. She was admitted to the hospital due to decline of language ability and irritability for 5 days. Blood tandem mass spectrometry and urine gas chromatography-mass spectrometry showed uracil and orotate increased significantly in urine while amino acids in the urea cycle ring were in the normal range. The features of brain MRI are consistent with those of urea circulatory disorders. Gene detection showed 1 novel mutation in the OTC gene (c.658C>T) in patient 1 and, 1 novel mutation (c.298+2T>G) in the OTC gene in patient 2. DIAGNOSIS: Combined with metabolic screening and gene detection, both patients were diagnosed with OTCD. INTERVENTIONS: The patients' condition improved after following a low protein diet and receiving treatments for decreasing blood ammonia, energy supplement, correcting acid-base imbalance, and other symptomatic treatments. OUTCOMES: After prompt symptomatic treatment, the consciousness and cognition of the children improved. Besides, liver function also improved significantly. CONCLUSIONS: For patients with neurological symptoms and unexplained increase in transaminase and ammonia, OTCD should be considered as a possible diagnosis. Brain MRI can help the diagnosis of genetic metabolic encephalopathy and reflect the level of brain injury. Metabolic screening and genetic detection are helpful to make a confirmed diagnosis.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Imagem por Ressonância Magnética , Doença da Deficiência de Ornitina Carbomoiltransferase/diagnóstico por imagem , Espectrometria de Massas em Tandem , Pré-Escolar , Feminino , Humanos , Lactente , Doença da Deficiência de Ornitina Carbomoiltransferase/genética
14.
BMC Ophthalmol ; 19(1): 168, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375076

RESUMO

BACKGROUND: Age-related macular degeneration (AMD) is the primary cause of blindness and severe vision loss in developed countries and is responsible for 8.7% of blindness globally. Ultraviolet radiation can induce DNA breakdown, produce reactive oxygen species, and has been implicated as a risk factor for AMD. This study investigated the effects of UVA radiation on Human retinal pigment epithelial cell (ARPE-19) growth and protein expression. METHODS: ARPE-19 cells were irradiated with a UVA lamp at different doses (5, 10, 20, 30 and 40 J/cm2) from 10 cm. Cell viability was determined by MTT assay. Visual inspection was first achieved with inverted light microscopy and then the DeadEnd™ Fluorometric TUNEL System was used to observe nuclear DNA fragmentation. Flow cytometry based-Annexin V-FITC/PI double-staining was used to further quantify cellular viability. Mitochondrial membrane potential was assessed with JC-1 staining. 2D electrophoresis maps of exposed cells were compared to nonexposed cells and gel images analyzed with PDQuest 2-D Analysis Software. Spots with greater than a 1.5-fold difference were selected for LC-MS/MS analysis and some confirmed by western blot. We further investigated whether caspase activation, apoptotic-related mitochondrial proteins, and regulators of ER stress sensors were involved in UVA-induced apoptosis. RESULTS: We detected 29 differentially expressed proteins (9 up-regulated and 20 down-regulated) in the exposed cells. Some of these proteins such as CALR, GRP78, NPM, Hsp27, PDI, ATP synthase subunit alpha, PRDX1, and GAPDH are associated with anti-proliferation, induction of apoptosis, and oxidative-stress protection. We also detected altered protein expression levels among caspases (caspase 3 and 9) and in the mitochondrial (cytosolic cytochrome C, AIF, Mcl-1, Bcl-2, Bcl-xl, Bax, Bad, and p-Bad) and ER stress-related (p-PERK, p-eIF2α, ATF4 and CHOP) apoptotic pathways. CONCLUSIONS: UVA irradiation suppressed the proliferation of ARPE-19 cells in a dose-dependent manner, caused quantitative loses in transmembrane potential (ΔΨm), and induced both early and late apoptosis.


Assuntos
Degeneração Macular/patologia , Estresse Oxidativo , Proteômica/métodos , Epitélio Pigmentado da Retina/metabolismo , Raios Ultravioleta , Apoptose , Sobrevivência Celular , Células Cultivadas , Cromatografia Líquida , Citocromos c/metabolismo , Humanos , Degeneração Macular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/patologia , Epitélio Pigmentado da Retina/efeitos da radiação , Transdução de Sinais , Espectrometria de Massas em Tandem
16.
Chem Pharm Bull (Tokyo) ; 67(8): 839-848, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366833

RESUMO

Panacis Japonici Rhizoma (PJR) contains various kinds of saponins, which possesses extensive pharmacological activities, but studies of comprehensive analysis of its saponins were limited. Thus, ultra-fast liquid chromatography coupled with triple quadrupole-time of flight tandem mass spectrometry (UFLC-Triple TOF-MS/MS) and ultra-fast liquid chromatography coupled with triple quadrupole-linear ion trap tandem mass spectrometry (UFLC-QTRAP-MS/MS) methods were established for the qualitative and quantitative analysis of the saponins in PJR, separately. Fifty three saponins in PJR were identified by UFLC-Triple TOF-MS/MS method, 23 saponins of which were unequivocally identified by reference substances. In addition, fragmentation pathways of different types of saponins were preliminarily deduced by fragmentation behavior of 53 saponins. Furthermore, the simultaneous determination of the contents of 13 saponins in PJR samples harvested at different times were analyzed by UFLC-QTRAP-MS/MS method. Furthermore, the quality of the samples was evaluated by grey relational analysis. This study might be beneficial to the quality assessment and control of PJR. Meanwhile, it might provide the basic information for confirming its optimal harvested period.


Assuntos
Rizoma/química , Saponinas/análise , Cromatografia Líquida , Conformação Molecular , Espectrometria de Massas em Tandem , Fatores de Tempo
17.
J Agric Food Chem ; 67(33): 9295-9306, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31365237

RESUMO

As a result of an innovative olive fruit processing method involving stone removal and dehydration, a new kind of olive oil and olive flour are generated. The main objective of this work was to accomplish the comprehensive characterization of the minor compounds of both products and to evaluate the effect of the dehydration temperature on their composition. To this end, olive oil and flour samples obtained through the novel processing method were analyzed and compared with "conventional" virgin olive oils (VOO). The applied LC-MS methodology allowed the determination of 57 metabolites belonging to different chemical classes (phenolic compounds, pentacyclic trirterpenes, and tocopherols). Both the new oils and flours presented considerable amounts of olive fruit metabolites that are usually absent from VOO. Quantitative differences were found among VOOs and the new oils, probably due to the inhibition of some enzymes caused by the temperature increase or the absence of water during the processing.


Assuntos
Manipulação de Alimentos/métodos , Olea/química , Extratos Vegetais/química , Resíduos/análise , Cromatografia Líquida , Farinha/análise , Frutas/química , Azeite de Oliva/análise , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas em Tandem , Tocoferóis/química , Tocoferóis/isolamento & purificação
18.
J Agric Food Chem ; 67(33): 9411-9422, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31393126

RESUMO

Royal jelly (RJ) is secreted by young worker bees, and it plays key roles in the development and physiological function in honeybees and can improve human health. Although there have been analyses on the glycosylation modification of RJ proteins, none of these methods have been conducted on a site-specific analysis of glycosylation from these glycoproteins. Here, a combined glycomics and glycoproteomics strategy was developed for the site-specific analysis of N-linked glycosylation heterogeneity of RJ glycoproteins. First, global characterization of the N-glycome of RJ was performed using a direct infusion ion trap-sequential mass spectrometry (IT-MSn) method. Second, tryptic glycopeptides were enriched and separated by hydrophilic interaction liquid chromatography-ion trap-sequential mass spectrometry (HILIC-IT-MSn). A total of 50 N-glycopeptides and 30 N-glycans have been site-specific glycosylation profiled in major royal jelly protein 1 (MRJP1) and MRJP2 of RJ for the first time. Eighteen of the identified N-glycans have been structurally characterized by IT-MSn, including oligosaccharide composition, sequence, branching, and linkage. Two N-glycosylation sites (N177 and N394), 3 sites (N145, N178, and N92), and 1 site of N183 were identified in MRJP1, MRJP2, and MRJP3, respectively. There were 18, 17, and 2 N-glycans attached to MRJP1, MRJP2, and MRJP3, respectively. The diversity of N-glycans attached to each single glycosylation site of these glycoproteins confirmed that MRJP1 and MRJP2 heterogeneity was mostly associated with their glycoform populations. Understanding the properties of the site-specific glycosylation heterogeneity of the RJ glycoproteins can be potentially useful for producing a glycoprotein with desirable pharmacokinetic and biological activity.


Assuntos
Ácidos Graxos/química , Glicoproteínas/química , Proteínas de Insetos/química , Motivos de Aminoácidos , Animais , Abelhas , Cromatografia Líquida , Glicômica , Glicosilação , Espectrometria de Massas em Tandem
19.
Shokuhin Eiseigaku Zasshi ; 60(3): 52-60, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31391411

RESUMO

We developed an analytical method for determining 15 antifungal drugs, 2 antiparasitic drugs, and 3 veterinary drugs in fish and livestock products using LC-MS/MS. First, 50% ethanol was added to their products, and the mixture was homogenized to reduce drug degradation. Thereafter, 20 drugs were extracted from the pretreated sample mixture using acetonitrile. Cleanup was performed using an alumina-N SPE cartridge. Finally, chromatographic separation was performed using a fully porous octadecyl silanized silica column. The new method is applicable to fish in which the matrix hampers accurate analysis. It was validated on 8 fish and livestock products. Drug recovery rates ranged from 70.2 to 109.3%, RSDs of repeatability were <18.0%, and RSDs of within-laboratory reproducibility were <18.7%. It fulfills the Japanese guideline criteria. The limits of quantification were estimated as 3 ng/g.


Assuntos
Antifúngicos/análise , Contaminação de Alimentos/análise , Carne/análise , Alimentos Marinhos/análise , Drogas Veterinárias/análise , Animais , Cromatografia Líquida , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
20.
Shokuhin Eiseigaku Zasshi ; 60(3): 61-67, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31391412

RESUMO

A method was developed for the determination of nonvolatile amines, such as histamine, tyramine, putrescine, and cadaverine, in foods. These nonvolatile amines were extracted from a sample with 5% trichloroacetic acid, and the extract was purified using an InertSep MC-1 cartridge column. The four amines were derivatized with fluorescamine, determined by HPLC with a fluorescence detector, and confirmed by LC-MS/MS. The average recoveries (n=5) and the relative standard deviations from 11 foods (pacific saury, dried mackerel, canned mackerel in brine, canned tuna in oil, fish sauce, surimi, rice-koji miso, soy sauce, gouda cheese, red wine, and beer) spiked at 100 mg/kg were 81-100% and 0.4-3.1%, respectively.


Assuntos
Aminas/análise , Fluorescamina , Análise de Alimentos/métodos , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
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