Coupling Of Liquid Chromatography Research Articles

Cross platform solutions to improve the zebrafish polar metabolome coverage using LC-QTOF MS: Optimization of separation mechanisms, solvent additives, and resuspension solvents

Untargeted metabolomics has been widely used for studies with zebrafish embryos. Until now, the number of analytical approaches to determine metabolites in zebrafish is limited, and there is a lack of consensus on the best platforms for comprehensive metabolomics analysis of zebrafish embryos. In addition, the capacity of these methods to detect metabolites is unsatisfactory and the confidence level for identifying compounds is relatively low. To improve the metabolome coverage, we mainly focused on the optimization of separation mechanisms, mobile phase additives, and resuspension solvents based on liquid chromatography (LC) coupling to high-resolution mass spectrometry (HRMS) techniques. Moreover, the procedures for optimizing methods were assessed when taking metabolite profiles in both positive and negative ionization modes into account. Four LC columns were studied: C18, T3, PFP, and HILIC. In positive ionization mode, it was strongly recommended to employ the HILIC approach operated at the neutral condition, which led to the presence of more than 4700 features and the annotation of 151 metabolites, mainly zwitterionic and basic compounds, in comparison to reverse phase (RP)-based methods with less than 1000 features. In negative ionization mode, the PFP column operated at 0.02% acetic acid showed the best performance in terms of metabolite coverage: 3100 metabolic features were detected and 218 metabolites were annotated in zebrafish embryos. Metabolite profiles mainly contained acidic and zwitterionic compounds. HILIC-based platforms were complementary to RP columns when analyzing highly polar metabolites. Additionally, it was preferable to reconstitute zebrafish extracts in 100% water for analysis of metabolites on RP columns, with a 20–30% increase in the number of identified metabolites compared to a 50% water in methanol solution. However, water/methanol (1:9, v/v), as resuspension solution, was advantageous over water/methanol (1:1, v/v) for HILIC analysis showing an 8–15% increase in detected metabolites. In total 336 polar metabolites were annotated by the combination of the optimized HILIC (positive) and PFP (negative) approaches. The largest metabolome coverage of polar metabolites in zebrafish embryos was obtained when three approaches were combined (negative PFP and HILIC, and HILIC positive) resulting in more than 420 annotated compounds.

Speciation and bioavailability of mercury in sediments from Mokolo River, Limpopo Province, South Africa

The presence of coal-based power plants and coal mine in the Waterberg area subjects the Mokolo River to potentially toxic elements (PTEs) such as mercury (Hg). Mercury is an extremely toxic element. Thus, monitoring and chemical speciation of Hg in water bodies; particularly in sediments is a vital tool for assessing water quality. The objective of this study was to investigate the levels of Hg(II) and methyl Hg (MeHg(I)) in sediment samples collected from Mokolo River in different seasons, as well as examining factors such as pH, temperature and organic matter content, which could affect Hg methylation rates. An ultrasonic based method was used for the extraction of Hg species in sediments. This was followed by the chromatographic separation and detection of Hg(II) and MeHg(I) by the on-line coupling of high-performance liquid chromatography (HPLC) to inductively coupled plasma-mass spectrometry (ICP-MS). A solution containing HCl and 2-mercaptoethanol was employed for the extraction of Hg species in sediments. Separation of the two species of Hg was achieved using isocratic elution mode with a mobile phase containing L-cysteine, 2-mercaptoethanol, ammonium acetate and methanol. The accuracy of the method was checked and yielded a percentage recovery of 86%. The Hg(II) concentrations ranged from 38.4 to 89.05 ng g−1 and 34.8 to 57.3 ng g−1 in low and high flow seasons, respectively. The concentrations of MeHg(I) ranged from 0.702 to 4.5 ng g−1 and 0.5 to 2.5 ng g−1 in the low and high flow seasons, respectively. Factors such as pH and temperature were found to influence the methylation rates, however correlation couldn’t be established to organic matter content due to similar amount of organic matter in all the samples.

An Automated Methodology for Non-targeted Compositional Analysis of Small Molecules in High Complexity Environmental Matrices Using Coupled Ultra Performance Liquid Chromatography Orbitrap Mass Spectrometry.

The life-critical matrices of air and water are among the most complex chemical mixtures that are ever encountered. Ultrahigh-resolution mass spectrometers, such as the Orbitrap, provide unprecedented analytical capabilities to probe the molecular composition of such matrices, but the extraction of non-targeted chemical information is impractical to perform via manual data processing. Automated non-targeted tools rapidly extract the chemical information of all detected compounds within a sample dataset. However, these methods have not been exploited in the environmental sciences. Here, we provide an automated and (for the first time) rigorously tested methodology for the non-targeted compositional analysis of environmental matrices using coupled liquid chromatography–mass spectrometric data. First, the robustness and reproducibility was tested using authentic standards, evaluating performance as a function of concentration, ionization potential, and sample complexity. The method was then used for the compositional analysis of particulate matter and surface waters collected from worldwide locations. The method detected >9600 compounds in the individual environmental samples, arising from critical pollutant sources, including carcinogenic industrial chemicals, pesticides, and pharmaceuticals among others. This methodology offers considerable advances in the environmental sciences, providing a more complete assessment of sample compositions while significantly increasing throughput.

Revisão sobre cromatografia líquida acoplada à espectrometria de massas aplicada à análise toxicológica de alimentos

A cromatografia líquida de alta eficiência (HPLC) acoplada à espectrometria de massas (EM) constitui-se como uma das mais importantes técnicas analíticas utilizadas na determinação de compostos não voláteis ou instáveis termicamente. A combinação de ambas une a excelência da separação do analito de interesse na matriz através da técnica da cromatografia líquida de alto desempenho, juntamente com a técnica da espectrometria de massas que confirma a identificação química. Dentre as alternativas disponíveis, a espectrometria de massas é a que melhor fornece as informações estruturais necessárias. O acoplamento entre estas duas técnicas dá origem a uma ferramenta analítica robusta, versátil e de grande potencial na análise qualitativa e quantitativa em toxicologia de alimentos. O presente artigo apresenta uma revisão de literatura que tem o objetivo de apresentar os fundamentos da aplicação do acoplamento da Cromatografia Líquida e Espectrometria de Massas na área de análise de alimentos.

Surface contamination with nine antineoplastic drugs in 109 canadian centers; 10 years of a monitoring program.

Healthcare workers exposure to antineoplastic drugs can lead to adverse health effects. Guidelines promote the safe handling of antineoplastic drugs, but no safe exposure limit was determined. Regular surface sampling contributes to ensuring workers safety. A cross-sectional monitoring is conducted once a year with voluntary Canadian centers, since 2010. Twelve standardized sampling sites were sampled. Samples were analyzed by high performance mass coupled liquid chromatography. The limits of detection (in ng/cm2) were: 0.001 for cyclophosphamide and gemcitabine; 0.3 for docetaxel and ifosfamide; 0.04 for 5-fluorouracil and paclitaxel; 0.003 for irinotecan; 0.002 for methotrexate; 0.01 for vinorelbine. The surfaces from 109 centers were sampled between 01/01/2020-18/06/2020. Twenty-six centers delayed their participation because of the COVID-19 pandemic. 1217 samples were analyzed. Surfaces were frequently contaminated with cyclophosphamide (34% positive, 75th percentile 0.00165 ng/cm2) and gemcitabine (16% and <0.001 ng/cm2). The armrest of patient treatment chairs (84% to at least one drug), the front grille inside the biological safety cabinet (BSC) (73%) and the floor in front of the BSC (55%) were frequently contaminated. Centers that prepared ≥5000 antineoplastic drugs annually had higher concentration of cyclophosphamide on their surfaces (p < 0.0001). Contamination measured on the surfaces was reduced from 2010 to 2020. This large-scale study showed reproducible long term follow up of the contamination of standardized sites of Canadian centers and a reduction in surface contamination from 2010 to 2020. Periodic surface sampling help centers meet their continuous improvements goals to reduce exposure as much as possible. The COVID-19 pandemic had a limited impact on the program.

Selenium Species Determination in Se-Enriched Grain Crops with Foliar Spray of Sodium Selenite by IP-RP-HPLC-UV-HG-AFS

A simple, rapid, and accurate method for determination of selenocystine (SeCys2), methyl selenocysteine (MeSeCys), selenourea (SeUr), selenite (Se(IV)), selenotmethionine (SeMet), and selenate (Se(VI)) in grain crops was developed, based on the coupling of ion-pair reversed-phase high-performance liquid chromatography (IP-RP-HPLC) and ultraviolet irradiation hydride generation atomic fluorescence spectrometry (UV-HG-AFS). The conditions of IP-RP-HPLC-UV-HG -AFS were studied. The conditions of the pretreatment sample, such as types and dosage of proteinases, were investigated. The detection limits (LODs) for six Se species were between 0.77 and 1.77 μg·L−1. Then, the proposed method has been successfully used to analyze selenium (Se) species in Se-enriched rice paddy (Oryza sativa L.), soybean (Glycine max (Linn.) Merr.), and sweet potato (Ipomoea batatas (L.) Lam.) with foliar application of sodium selenite solution. SeMet was the major Se spices in Se-enriched grain crops, ranged from 77–90% of the total Se contents. The capabilities of Se enrichment were relatively larger differences in three-grain corps as follows: soybean > rice paddy > sweet potato.

Label-Free Protein Analysis Using Liquid Chromatography with Gravimetric Detection.

The detection and analysis of proteins in a label-free manner under native solution conditions is an increasingly important objective in analytical bioscience platform development. Common approaches to detect native proteins in solution often require specific labels to enhance sensitivity. Dry mass sensing approaches, by contrast, using mechanical resonators, can operate in a label-free manner and offer attractive sensitivity. However, such approaches typically suffer from a lack of analyte selectivity as the interface between standard protein separation techniques and micro-resonator platforms is often constrained by qualitative mechanical sensor performance in the liquid phase. Here, we describe a strategy that overcomes this limitation by coupling liquid chromatography with a quartz crystal microbalance (QCM) platform by using a microfluidic spray dryer. We explore a strategy which allows first to separate a protein mixture in a physiological buffer solution using size exclusion chromatography, permitting specific protein fractions to be selected, desalted, and subsequently spray-dried onto the QCM for absolute mass analysis. By establishing a continuous flow interface between the chromatography column and the spray device via a flow splitter, simultaneous protein mass detection and sample fractionation is achieved, with sensitivity down to a 100 μg/mL limit of detection. This approach for quantitative label-free protein mixture analysis offers the potential for detection of protein species under physiological conditions.

Relationships between constituents of energy drinks and beating parameters in human induced pluripotent stem cell (iPSC)-Derived cardiomyocytes

Consumption of energy drinks has been associated with adverse cardiovascular effects; however, little is known about the ingredients that may contribute to these effects. We therefore characterized the chemical profiles and in vitro effects of energy drinks and their ingredients on human induced pluripotent stem cell (iPSC)-derived cardiomyocytes, and identified the putative active ingredients using a multivariate prediction model. Energy drinks from 17 widely-available over-the-counter brands were evaluated in this study. The concentrations of six common ingredients (caffeine, taurine, riboflavin, pantothenic acid, adenine, and L-methionine) were quantified by coupling liquid chromatography with a triple quadrupole mass spectrometer for the acquisition of LC-MS/MS spectra. In addition, untargeted analyses for each beverage were performed with a platform combining LC, ion mobility spectrometry and mass spectrometry (LC-IMS-MS) measurements. Approximately 300 features were observed across samples in the untargeted studies, and of these ~100 were identified. In vitro effects of energy drinks and some of their ingredients were then tested in iPSC-derived cardiomyocytes. Data on the beat rate (positive and negative chronotropy), ion channel function (QT prolongation), and cytotoxicity were collected in a dilution series. We found that some of the energy drinks elicited adverse effects on the cardiomyocytes with the most common being an increase in the beat rate, while QT prolongation was also observed at the lowest concentrations. Finally, concentration addition modeling using quantitative data from the 6 common ingredients and multivariate prediction modeling was used to determine potential ingredients responsible for the adverse effects on the cardiomyocytes. These analyses suggested theophylline, adenine, and azelate as possibly contributing to the in vitro effects of energy drinks on QT prolongation in cardiomyocytes.

Coupling liquid chromatography and inductively coupled plasma-mass spectrometry with ultrasonic nebulization for chromium speciation in rice

Liquid chromatography and dynamic reaction cell inductively coupled plasma mass spectrometry are used in tandem for the determination of chromium compounds in rice powder.

Direct determination of Pb isotope ratios in archaeological materials by coupling liquid chromatography to multicollector ICP-MS

On-line coupling of HPLC-MC-ICP-MS allows Pb isotope ratio measurements in archaeological samples without prior off-line Pb separation.

Untargeted Metabolomics Studies on Drug-Incubated Phragmites australis Profiles.

Plants produce a huge number of functionally and chemically different natural products that play an important role in linking the plant with the adjacent environment. Plants can also absorb and transform external organic compounds (xenobiotics). Currently there are only a few studies concerning the effects of xenobiotics and their transformation products on plant metabolites using a mass spectrometric untargeted screening strategy. This study was designed to investigate the changes of the Phragmites australis metabolome following/after diclofenac or carbamazepine incubation, using a serial coupling of reversed-phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) combined with accurate high-resolution time-of-flight mass spectrometer (TOF-MS). An untargeted screening strategy of metabolic fingerprints was developed to purposefully compare samples from differently treated P. australis plants, revealing that P. australis responded to each drug differently. When solvents with significantly different polarities were used, the metabolic profiles of P. australis were found to change significantly. For instance, the production of polyphenols (such as quercetin) in the plant increased after diclofenac incubation. Moreover, the pathway of unsaturated organic acids became more prominent, eventually as a reaction to protect the cells against reactive oxygen species (ROS). Hence, P. australis exhibited an adaptive mechanism to cope with each drug. Consequently, the untargeted screening approach is essential for understanding the complex response of plants to xenobiotics.

Untargeted Analysis for Mycosporines and Mycosporine-Like Amino Acids by Hydrophilic Interaction Liquid Chromatography (HILIC)-Electrospray Orbitrap MS2/MS3.

Mycosporines and mycosporine-like amino acids have been described as natural sunscreens and antioxidant compounds presenting a great potential for health and cosmetic applications. Herein, an untargeted screening approach for mycosporines and mycosporine-like amino acids (MAAs) was developed by the coupling of zwitterionic hydrophilic interaction liquid chromatography (HILIC) with multistage electrospray mass spectrometry MS2/MS3 using an Orbitrap analyzer and fragment ion search (FISh). This method was applied to study the mycosporine and MAA contents of five algae extracted using a 50% methanol solution and sonication. Candidate-MAAs were detected by mining eight characteristic fragment ions in their HILIC data-dependent MS2 mass spectrum. Their exact masses were measured with 3 ppm mass accuracy and their structures were elucidated on the basis of the MS3/MS4 mass spectra. The method developed was validated with a targeted analysis using an extract of Gymnogongrus devoniensis which confirmed the detection of 14 MAAs reported in the literature. In addition, 23 previously unreported MAAs were detected and the structures could be assigned for seven of them. The developed method was applied to the analysis of four algae: Gelidium sesquipedale, Halopithys incurva, Porphyra rosengurtii and Cystoseira tamariscifolia allowing the detection of MAAs, including some reported here for the first time.

Rapid Characterization of Emerging Per- and Polyfluoroalkyl Substances in Aqueous Film-Forming Foams Using Ion Mobility Spectrometry-Mass Spectrometry.

Aqueous film-forming foams (AFFF) are mixtures formulated with numerous hydrocarbon- and fluoro-containing surfactants. AFFF use leads to environmental releases of unknown per- and polyfluoroalkyl substances (PFAS). AFFF composition is seldom disclosed, and their use elicits concerns from both regulatory agencies and the public because PFAS are persistent in the environment and potentially associated with adverse health effects. In this study, we demonstrate the use of coupled liquid chromatography, ion mobility spectrometry, and mass spectrometry (LC-IMS-MS) to rapidly characterize both known and unknown PFAS in AFFF. Ten AFFF formulations from seven brands were analyzed using LC-IMS-MS in both negative and positive ion modes. Untargeted analysis of the formulations was followed by feature identification of PFAS-like features utilizing database matching, mass defect and homologous series evaluation, and MS/MS fragmentation experiments. Across the tested AFFF formulations, we identified 33 homologous series; only ten of these homologous series have been previously reported. Among tested AFFF, the FireStopper (n = 85) contained the greatest number of PFAS-like features and Phos-Check contained zero. This work demonstrates that LC-IMS-MS-enabled untargeted analysis of complex formulations, followed by feature identification using data-processing algorithms, can be used for rapid exposure characterization of known and putative PFAS during fire suppression-related contamination events.

Oxidation of di-n-propyl ether: Characterization of low-temperature products

The oxidation of di-n-propyl-ether (DPE) was performed in a jet-stirred reactor at 1 and 10 atm, at residence times of 1 and 0.7 s, respectively, and initial fuel concentrations of 5000 and 1000 ppm at 1 and 10 atm, respectively. Atmospheric pressure experiments were used for characterization of cool flame products. The 10 atm experiment provided KHPs profile vs. temperature and mole fraction profiles of stable species which were obtained through sonic probe sampling, gas chromatography, Fourier transform infrared spectrometry analyses. High resolution mass spectrometry analyses (HRMS) with syringe direct injection or ultra-high-pressure liquid chromatography coupling was used to characterize hydroperoxides (C3H8O2, C6H14O3), diols (C6H14O3), ketohydroperoxides (C6H12O4), carboxylic acids, and highly oxygenated molecules (C6H12O6, C6H12O8) resulting from up to four O2 additions on fuel's radicals. Heated electrospray and atmospheric pressure chemical ionizations (HESI and APCI) were used in positive and negative mode. Whereas the CH2 groups neighboring the ether function are the most favorable sites for H-atom abstraction reactions, speciation indicated that other sites can react by metathesis forming a large pool of intermediates. Our kinetic reaction mechanism represents the experimental data for most of the stable species but need to be expended for simulating the formation of newly detected species.

Isobaric Tagging for Relative and Absolute Protein Quantification (iTRAQ)-Based Quantitative Proteomics Analysis of Differentially Expressed Proteins 1 Week After Spinal Cord Injury in a Rat Model.

BackgroundSpinal cord injury (SCI) is a devastating trauma of the central nervous system (CNS), with high levels of morbidity, disability, and mortality. One week after SCI may be a critical time for treatment. Changes in protein expression have crucial functions in nervous system diseases, although the effects of changes occurring 1 week after SCI on patient outcomes are unclear.Material/MethodsProtein expression was examined in a rat contusive SCI model 1 week after SCI. Differentially expressed proteins (DEPs) were identified by isobaric tagging for relative and absolute protein quantification (iTRAQ)-coupled liquid chromatography tandem-mass spectrometry (LC-MS/MS) proteomics analysis. Gene Ontology (GO) analysis was performed to identify the biological processes, molecular functions, and cellular component terms of the identified DEPs, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) was used to identify key enriched pathways. Protein–protein interaction (PPI) networks were analyzed to identify the top 10 high-degree core proteins.ResultsOf the 295 DEPs identified, 204 (69.15%) were upregulated and 91 (30.85%) were downregulated 1 week after injury. The main cellular components, molecular functions, biological processes, and pathways identified may be crucial mechanisms involved in SCI. The top 10 high-degree core proteins were complement component C3 (C3), alpha-2-HS-glycoprotein (Ahsg), T-kininogen 1 (Kng1), Serpinc1 protein (Serpinc1), apolipoprotein A-I (Apoa1), serum albumin (Alb), disulfide-isomerase protein (P4hb), transport protein Sec61 subunit alpha isoform 1 (Sec61a1), serotransferrin (Tf), and 60S ribosomal protein L15 (Rpl15).ConclusionsThe proteins identified in this study may provide potential targets for diagnosis and treatment 1 week after SCI.

Oxidation of di-n-butyl ether: Experimental characterization of low-temperature products in JSR and RCM

The oxidation of di-n-butyl-ether (DBE) was performed in a jet-stirred reactor (JSR) at 1 atm, 520 and 530 K, and from 480 to 670 K at 10 atm, at a residence time of 1 s, an equivalence ratio of 0.5, and an initial fuel concentration of 5000 ppm. Ignition experiments on DBE/air mixtures were also performed in a rapid compression machine (RCM) under stoichiometric conditions, 5 bar, and from 550 to 630 K. Low-temperature products formed in JSR and RCM experiments were characterized. To this end, high-resolution mass spectrometry analyses (HRMS) with flow injection analyses or ultra-high pressure liquid chromatography coupling were used to characterize hydroperoxides and diols (C8H18O3), ketohydroperoxides (C8H16O4), carboxylic acids (C2H4O2, C3H6O2, C4H8O2), di-keto ethers (C8H14O3), and highly oxygenated molecules (C8H14O5, C8H16O6, C8H14O6, C8H14O7, C8H16O8, and C8H14O9) resulting from up to five O2 additions on fuel's radicals. Whereas HOMs are of minor importance in combustion, they are considered key species for the formation of secondary organic aerosols. In addition, cyclic ethers and esters (C8H16O2) were observed. Heated electrospray and atmospheric pressure chemical ionizations (HESI and APCI) were used in positive and negative modes for MS analyses. H/D exchange with D2O was used to confirm the presence of –OH or –OOH groups in the products. The present results show that DBE oxidation proceeds similarly under JSR and RCM conditions. Whereas the CH2 groups neighboring the ether group are the most favorable sites for H-atom abstraction reactions, speciation indicated that other sites can react by metathesis forming a large pool of intermediates and products. Our kinetic reaction mechanism needs to be extended for simulating the formation of newly detected species.

Automated needle-sleeve based online hyphenation of solid-phase microextraction and liquid chromatography

A novel approach for the online coupling of solid-phase microextraction (SPME) and liquid chromatography (LC) is introduced. An innovative Si@GO@βCD coated needle-sleeve extractant device was developed and then employed in the automated online SPME-LC-UV determination of estrogen-like isoflavones from human urine samples. The extractant SPME device is easily attachable at the endpoint of an analytical syringe needle and operated by a lab-made autosampler. Fully automated online SPME-LC is accomplished by proper autosampler programming to perform the following steps: i) the analytes extraction by direct immersion of the extractant device into the stirred sample, ii) a rinsing step iii) the analytes desorption/enrichment, iv) the online transference of the extract to the LC injection valve. Besides allowing the online SPME hyphenation, this extraction modality efficiently addressed the drawbacks associated with the clogging and dispersion of graphene-based microextraction techniques performed in packed-bed and dispersive formats. The main extraction parameters and the performance of the automated online SPME-LC method developed were carefully studied. The results show a good sensitivity, reliability, and straightforward analytical strategy for the determination of organic compounds in complex samples. The detection limit of the method was 20 μg L1 for DAI and 10 μg L−1 for GEN, FOR and BIO. The intra-day RSD was below 10% and inter-day RSD was below 13%. The total analysis time was less than 17 min per sample.

Advances in Detecting Ciguatoxins in Fish.

Ciguatera fish poisoning (CFP) is currently the most common marine biotoxin food poisoning worldwide, associated with human consumption of circumtropical fish and marine invertebrates that are contaminated with ciguatoxins. Ciguatoxins are very potent sodium-channel activator neurotoxins, that pose risks to human health at very low concentrations (>0.01 ng per g of fish flesh in the case of the most potent Pacific ciguatoxin). Symptoms of CFP are nonspecific and intoxication in humans is often misdiagnosed. Presently, there is no medically approved treatment of ciguatera. Therefore, to mitigate the risks of CFP, reliable detection of ciguatoxins prior to consumption of fish tissue is acutely needed, which requires application of highly sensitive and quantitative analytical tests. During the last century a number of methods have been developed to identify and quantify the concentration of ciguatoxins, including in vivo animal assays, cell-based assays, receptor binding assays, antibody-based immunoassays, electrochemical methods, and analytical techniques based on coupling of liquid chromatography with mass spectrometry. Development of these methods, their various advantages and limitations, as well as future challenges are discussed in this review.

Metabonomic study with a high performance liquid chromatography coupling to a triple quadruple mass spectrometer to identify biomarkers from urine of high-fat fed and streptozotocin treated rats

High performance liquid chromatography coupled with an electrospray ionization (ESI) tandem mass (MS/MS) detector was employed to scan the urinary metabolites of Wistar rats (n=5 each group) fed with either control diet or high fat diet with a single dose of streptozotocin (STZ) for 14 weeks. Principle component analysis (PCA) of the LC-MS data was performed for pattern re-cognition and it clearly showed that the dosed animals displayed different metabolic responses even though they received the same treatment. Components responsible for the separation were identified with MS/MS. Glucose and malonic acid were among some other components in Krebs cycle to show high loading strength in PCA. It was therefore postulated that the high fat diets have driven the animals toward the metabolic flux to gluconeogenesis and then energy production through Krebs cycle. Excess energy was also stored through fatty acid biosynthesis with the observation of high loading strength of malonic acid. This experiment demonstrated that a triple quadruple mass spectrophotometer is capable of the metabonomic study on diet modulation of animals. Since metabonomics is a congruous part of nutrigenomics that can provide information on nutritional status, toxicity and gene function of an organism, it is hoped that this technique be extended to study the efficacy of functional foods and the development of personalized foods.

Quantitative Proteomics Analysis of Systemic Responses and Biological Mechanisms of ShuFengJieDu Capsule Using H1N1-Infected RAW264.7 Cells

Emerging infectious diseases (EIDs) are a significant burden on global economies and public health to any country in the world. With the extensive application of traditional Chinese medicines (TCMs) for EID treatment, the underlying molecular mechanisms have caught more attention than before. The ShuFengJieDu capsule (abbreviated as SFJD) is a TCM prescription used for treating upper respiratory infection (URI) with symptoms of fever, sore throat, headaches, nasal congestion, and cough for more than 30 years in China. SFJD is also widely used for the prevention and treatment of viral infectious diseases, especially for the EIDs. In this study, a bioactivity-integrated method of ultraperformance liquid chromatography quadrapole/time-of-flight mass spectrometry combined with methyl thiazolyl tetrazolium assay was applied to screen potential antivirus compounds in SFJD on the H1N1-infected RAW264.7 cell models. Three compounds (forsythoside E, verbenalin, and emodin) exert the advantages of protective effects in cell vitality during H1N1 infection. The isobaric tags for relative and absolute quantification (iTRAQ)-coupled liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) analysis and the subsequent quantitative proteome analysis were performed to investigate the potential molecular mechanisms triggered by these three bioactive compound-triggered molecular mechanisms in H1N1-infected RAW264.7 cells. Dysregulated proteins were involved in regulating the levels of proinflammatory cytokines, the IFN (interferon)-stimulated gene signal in the Type I IFN, TBK/IRF3, and MAPK/NF-κB signaling pathways. In conclusion, we identified the main bioactive compounds in SFJD exerting antiviral effects and illuminated that Type I IFN and MAPK/NF-κB signaling pathways are involved in the anti-H1N1 infection effects of SFJD. Our study not only provides solid theoretical support for the clinic application of SFJD but also sheds light on the novel research methods for TCM study.