Ion Trap Tandem Mass Spectrometry Research Articles

Qualitative and Quantitative Analyses of Active Constituents in Trollius ledebourii.

Trollius ledebourii has been more involved in Mongolian medicine and is often used as a type of tea for heat-clearing and detoxifying in the populus. In this study, a rapid and sensitive method was established for the qualitative and quantitative analyses of the major constituents in T. ledebourii. Ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was developed for the identification of the multi-constituents in T. ledebourii. A total of 37 chemical constituents in T. ledebourii extract were unambiguously or tentatively identified, including 17 flavonoid glycosides, 6 flavones, 3 flavonols, 1 dihydroflavone, 8 phenolic acids, 1 amide and 1 triterpene. Pectolinarin, naringenin, isorhamnetin, diosmetin, protocatechuic acid, paeonol, caffeic acid and ferulic acid were first detected in T. ledebourii and the buttercup family. High-performance liquid chromatography-quadrupole ion trap tandem mass spectrometry was applied for the simultaneous determination of 11 compounds, which were either with high contents or strong bioactivities. Satisfactory linearity was achieved with a wide linear range and fine determination coefficient (r > 0.9987). The overall recoveries ranged from 98.07 to 101.2%, and the precision in terms of RSD was <0.74%. The results might provide the basis for quality control analysis of T. ledebourii.

Alisma orientale extract exerts the reversing cholestasis effect by activation of farnesoid X receptor

BackgroundCholestasis is a clinical syndrome of liver damage that is caused by accumulation of bile acids in the liver and systemic circulation. Farnesoid X receptor (FXR) can regulate synthesis, metabolism, and excretion of bile acids. The rhizomes of Alisma orientale is a well-known traditional Chinese medicine to treat edema, obesity, gonorrhea, leukorrhea, diarrhea, hyperlipidemia, and diabetes in China. Hypothesis/purposeWe hypothesized Alisma orientale extract (AOE) to exert hepatoprotective effect against α-naphthylisothiocyanate (ANIT) induced cholestasis in rat. We aimed to investigate the mechanism of AOE. Study designMale Sprague Dawley rats with intrahepatic cholestasis induced by ANIT were treated with AOE (150, 300, or 600 mg/kg). Rats receiving vehicle (0.5% CMC-Na) served as control. Methods48 h after ANIT administration, rats were sacrificed. Blood was collected to obtain serum and livers were removed for histopathology and protein preparation. Biochemical indicators in serum were determined using commercial kits and triterpenoids were determined by liquid chromatography tandem Qtrap mass spectrometry. Proteomics was analyzed by liquid chromatography tandem ion-trap mass spectrometry. The differently expressed proteins were analyzed via the network database and verified by western blotting. The interaction between triterpenoids and FXR were evaluated by luciferase assay and molecular docking. ResultsAOE treatment significantly decreased the serum AST, ALT, TBIL, and intrahepatic TBA and improved the liver pathologic change induced by ANIT. Proteomics analysis indicated that AOE regulated proteins related to bile acid homeostasis via activating farnesoid X receptor (FXR) signaling pathway. Luciferase assay and molecular docking results indicated that triterpenoids could activate FXR, which resulting in ameliorative accumulation of bile acids in the liver by increase of metabolism and transportation for bile acids, and decrease of synthesis for bile acids. ConclusionAOE protected against rat liver injury and cholestasis induced by ANIT by activation of farnesoid X receptor, suggesting that A. orientale could be regarded as a potential hepatoprotective drug.

Quality evaluation of Eucommiae Cortex processed by different methods and "sweating" conditions based on simultaneous determination of multiple bioactive constituents combined with gray relational analysis.

Eucommiae Cortex is a classical traditional Chinese medicine, which needs to be processed by "sweating" methods. To select the suitable processing method and "sweating" processing condition for Eucommiae Cortex, in this study, the quality of Eucommiae Cortex was evaluated based on simultaneous determination of multiple bioactive constituents combined with gray relational analysis. The contents of lignans, iridoids, penylpropanoids, flavonoids, and phenols in samples were simultaneously determined using ultra-fast performance liquid chromatography coupled with triple quadrupole-linear ion trap tandem mass spectrometry. The chromatographic separation was performed on a Synergiۛ Hydro-RP 100 Å column (100mm×2.0mm, 2.5μm) at 30°C with a gradient elution of acetonitrile with 0.1% formic acid/0.1% aqueous formic acid as the mobile phase. Furthermore, gray relational analysis was performed to evaluate and sort the samples according to the contents of 14 constituents by calculating the relative correlation degree of each sample. The results demonstrated that the quality of Eucommiae Cortex "sweating" at source area was better and the better "sweating" condition was to scrape off the cork layer before "sweating" with straw covering and sun drying. The developed method could provide the foundation and support for "sweating" processing method of Eucommiae Cortex in normalization and standardization.

Chemical Profile of the Sulphated Saponins from the Starfish Luidia senegalensis Collected as by-Catch Fauna in Brazilian Coast

The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are discarded because they do not have commercial value. In order to try to add some value to these materials, we analyzed the chemical composition of the starfish Luidia senegalensis collected in the Brazilian coast as a consequence of the trawling fishery method. In order to access their chemical composition, we used a combination of solid phase extraction (SPE) followed by ultra-high performance liquid chromatography coupled to electrospray ionization ion trap tandem mass spectrometry (UPLC-ESI-IT-MSn). Luidia senegalensis contains asterosaponins, which are sulphated glycosilated steroids, containing five and six sugar moieties, in addition to polyhydroxysteroids. This study helped us to support the presence of important and potentially bioactive compounds in invertebrates associated to the by-catch fauna of the shrimp fishery, using a fast and efficient method.Graphical

The UPLC–ESI–QqQLIT–MS/MS method for quantitative determination of phytochemicals in ethanolic extracts of different parts of eight Ficus species: Development and validation

ABSTRACTFicus and validation of the ultra performance liquid chromatography–electrospray ionization hybrid triple quadrupole–linear ion trap–tandem mass spectrometry (UPLC–ESI–QqQLIT–MS/MS) method in a multiple-reaction monitoring (MRM) mode for the quantitative determination of 19 phytochemicals. The chromatographic separation of targeted phytochemicals was performed using the Waters ACQUITY UPLC BEH™ C18 column (1.7 μm, 2.1 mm × 50 mm) with 0.1% formic acid with water and acetonitrile as a mobile phase at a flow rate of 0.25 mL/min. The validation parameters showed the overall recoveries from 95.78−101.44% (RSD ≤ 3.25%), precision (intra-day: RSD ≤ 2.96%; inter-day: RSD ≤ 2.89%), linearity (R2 ≥ 0.9982), limit of detection (8.60 × 10–10−2.18 × 10–6 mg/mL), and the limit of quantitation (2.60 × 10–9–6.63 × 10–6 mg/mL) in the concentration range from 0.5 to 1000 × 10–6 mg/mL. This method was successfully applied in ethanolic extracts of different parts (fruits, leaves, and barks) of selected eight Ficus species. Quinic acid was predominant followed by rutin and chlorogenic acid among the studied nineteen phytochemicals. Ficus benjamina showed the maximum total content in fruits and leaves. The UPLC–ESI–QqQLIT–MS/MS method combined with principal component analysis (PCA) was successfully used for Ficus species discrimination on the basis of the contents of 15 compounds. The UPLC–ESI–QqQLIT–MS/MS method combined with PCA could be used for quality control.

An optimized SPE-LC-MS/MS method for antibiotics residue analysis in ground, surface and treated water samples by response surface methodology- central composite design

BackgroundAntibiotic residues are being constantly identified in environmental waters at low concentration. Growing concern has been expressed over the adverse environmental and human health effects even at low concentration. Hence, it is crucial to develop a multi-residues analytical method for antibiotics to generate a considerable dataset which are necessary in the assessment of aquatic toxicity of environmental waters for aquatic organisms and human health. This work aimed to develop a reliable and sensitive multi-residue method based on high performance liquid chromatography coupled with quadrupole-linear ion trap tandem mass spectrometry (HPLC-MS-MS). The method was optimized and validated for simultaneous determination of four classes of antibiotics including, β-lactam, macrolide, fluoroquinolone and nitro-imidazole in treated, ground and surface water matrices.MethodsIn order to optimize the solid phase extraction process, main parameters influencing the extraction process including, pH, the volume of elution solvent and the amount of Na4EDTA were evaluated. The optimization of extraction process was carried out by response surface methodology using central composite design. Analysis of variance was performed for nine target antibiotics using response surface methodology.ResultsThe extraction recoveries were found to be sensitive to the independent variables of pH, the volume of elution solvent and the amount of Na4EDTA. The extraction process was pH-dependent and pH was a significant model term in the extraction process of all target antibiotics. Method validation was performed in optimum operation conditions in which the recoveries were obtained in the range of 50–117% for seven antibiotics in spiked treated and ground water samples and for six antibiotics in spiked river water samples. Method validation parameters in terms of method detection limit were obtained in the range of 1–10 ng/L in treated water, 0.8–10 ng/L in the ground water and 0.8–25 ng/L in river water, linearity varied from 0.95 to 0.99 and repeatability in term of relative standard deviation values was achieved less than 10% with the exception for metronidazole and ceftriaxone. The developed method was applied to the analysis of target antibiotics in treated, ground and surface water samples.ConclusionsTarget antibiotics were analyzed in different water matrices including treated, ground and river water. Seven out of nine antibiotics were detected in Kan River and Firozabad Ditch water samples, although none of them were detected in treated water and ground water samples.

The rapid determination of bromadiolone in liver and blood plasma by in-injector pyrolysis gas chromatography - Ion trap tandem mass spectrometry.

The unintentional poisoning of off-target animals by bromadiolone, a second generation anticoagulant rodenticide, is an undesirable outcome requiring sensitive analytical methods. In this study, a rapid and sensitive method for the determination of bromadiolone in liver and blood plasma by means of gas chromatography coupled with tandem mass spectrometry without need for derivatization was developed. The method is based on the in-injector pyrolysis of bromadiolone and subsequent gas chromatography coupled with ion trap tandem mass spectrometry with electron ionization. Sample preparation includes extraction with methanol, evaporation under nitrogen stream, and dissolution in toluene. The pyrolysis of bromadiolone was carried out in an injector at 390°C. Chromatographic separation of the pyrolytical fragment of bromadiolone was achieved using a VF-5ms column with helium as the mobile phase. Tandem in-time mass spectrometry of the separated pyrolytical fragment of bromadiolone was carried out using an ion trap mass spectrometer after electron ionization. Recovery ranged from 94 to 98%. The method showed good linearity up to 1000μgkg-1 for liver and 1000μgL-1 for plasma. The limit of detection was 0.38μgkg-1 for liver and 0.26μgL-1 for plasma. The developed method was used successfully in several animal poisoning cases.

Analysis and identification of chemical constituents of fenugreek by UPLC-IT-MS n and UPLC-Q-TOF-MS

Fenugreek, a traditional Chinese medical plant, has been widely used as food ingredients because of its outstanding medicinal qualities. The hypoglycemic activity of fenugreek is one of its important pharmacological properties. Both of saponin and flavonoid components have the hypoglycemic activity and their contents in fenugreek are 4%—8% and 1%—2%, respectively. This paper focused on these two types of components to carry out purification research and chemical analysis. The heating reflux extraction method and macroporous resin purification method were designed to prepare the saponins and the flavonoids components from defatted fenugreek seeds. Petroleum ether ultrasonic skim and 70% ethanol refluxing were used for the extraction of saponins and flavonoid from fenugreek. The column of DM130 macroporous resin and D101 macroporous resin were respectively used to prepare fenugreek saponin and flavonoid components, and the total contents of them were 78.56% and 62.28%, respectively. The saponin and flavonoids were subsequently analyzed by an ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) along with an ultra-performance liquid chromatography and ion-trap tandem mass spectrometry(UPLC-IT-MS n ). As a result, 57 saponins and 19 flavonoid compounds were characterized. The obtained results will provide a theory basis for further research on fenugreek, as well as research and development of hypoglycemic new drugs.

Determination of sterols and steroid hormones in surface water and wastewater using liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry

The development and optimization of an analytical method for simultaneous extraction, determination and reliable confirmation of twenty steroids from different classes (human/animal and plant sterols, and natural and synthetic steroid hormones) in environmental water and wastewater at ngL−1 levels are described. Water samples were prepared using solid-phase extraction and extracts were analyzed by liquid chromatography-linear ion trap-tandem mass spectrometry. Improved instrumental method was developed for complete chromatographic separation of analytes with identical fragmentation reactions, based on the use of a single C8 column and acetonitrile as organic solvent in the mobile phase. The optimized method provided high recoveries (70–114%) for both water matrices with the RSDs generally lower than 20%. Low limits of detection were achieved for both surface water (0.7–15.0ngL−1) and wastewater (1.7–15.0ngL−1). Method displayed good linearity in the tested concentration ranges. As a result of method application to real water samples, cholesterol was detected in all fifteen analyzed river water samples (in the concentration range 176–5162ngL−1) and all seven wastewater samples (1092–4808ngL−1). Also, coprostanol, stigmasterol, campesterol, β-sitosterol and sitostanol were found in the investigated samples. Steroid hormones were not detected in any of the analyzed water samples.

Dynamic changes of metabolite accumulation in Scrophulariae Radix based on liquid chromatography-tandem mass spectrometry combined with multivariate statistical analysis.

Scrophulariae Radix is one of the most popular traditional Chinese medicines. The harvesting time of Scrophulariae Radix is closely related to the quality of products in this traditional Chinese medicine. The goal of the study is to analyze the dynamic changes of metabolite accumulation in Scrophulariae Radix. The difference of constituents in Scrophulariae Radix harvested at different times was analyzed by liquid chromatography with triple quadrupole-time of flight tandem mass spectrometry coupled with principal component analysis and partial least-square discriminant analysis. According to the accurate mass of molecular and product ions provided by triple quadrupole-time of flight tandem mass spectrometry, a total of 30 differential constituents were identified. Furthermore, the contents of ten index differential constituents in Scrophulariae Radix were simultaneously determined by liquid chromatography coupled with triple quadrupole-linear ion trap tandem mass spectrometry. Gray relational analysis was performed to evaluate the samples harvested at different times according to the contents of ten constituents. All of the results demonstrated that the quality of Scrophulariae Radix collected at traditional harvest time was better. This study will provide the basic information for revealing the dynamic change law of metabolite accumulation of Scrophulariae Radix and exploring its quality forming mechanism.

Rapid Simultaneous Screening and Detection of 12 Anticoagulant Rodenticides in Food by Ultra-performance Liquid Chromatography-Triple Quadrupole/Linear Ion Trap Tandem Mass Spectrometry

A rapid analytical method for the simultaneous screening and detection of 12 anticoagulant rodenticides in food samples was established based on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation method using an ultra-performance liquid chromatography-triple quadrupole/linear ion trap tandem mass spectrometry (UPLC-QTrap-MS/MS). Food samples were extracted and purified with modified QuEChERS method. The 12 anticoagulant rodenticides (warfarin, brodifacoum, difethialone, coumachlor, coumatetralyl, bromadiolone, chlorophacinone, difenacoum, diphacinone, pindone, valone, and flocoumafen) and the internal standard (warfarin-D5) were separated within 6 min using an ACQUITY UPLC BEH-C18 column (1.7 μm, 2.1 mm × 50 mm) and gradient elution with the mobile phase consisting of 5 mM ammonium acetate formate buffer and acetonitrile. The multiple reaction monitoring-information dependent acquisition-enhanced product ion (MRM-IDA-EPI) scanning was employed for detection. The calibration curves were linear (R2 > 0.99) for all the compounds. The mean recoveries for the 12 analytes at three spiked levels (1× LOQ, 5× LOQ, and 10× LOQ) were in the range of 79.5–113.2% with RSDs of 1.8–13.2%.The limits of detection (LOD) for the 12 rodenticides ranged from 0.01 (warfarin) to 0.05 μg/kg (diphacinone). The limit of quantification (LOQ) for the 12 rodenticides was between 0.02 (warfarin) and 0.10 μg/kg (diphacinone). The developed method was more straightforward, less time and labor intensive, and more sensitive, selective, and accurate for screening multiple anticoagulant rodenticides, and it was successfully used in several poisoning cases.

Proteomic analysis of the dorsal spinal cord in the mouse model of spared nerve injury-induced neuropathic pain.

Peripheral nerve injury often causes neuropathic pain and is associated with changes in the expression of numerous proteins in the dorsal horn of the spinal cord. To date, proteomic analysis method has been used to simultaneously analyze hundreds or thousands of proteins differentially expressed in the dorsal horn of the spinal cord in rats or dorsal root ganglion of rats with certain type of peripheral nerve injury. However, a proteomic study using a mouse model of neuropathic pain could be attempted because of abundant protein database and the availability of transgenic mice. In this study, whole proteins were extracted from the ipsilateral dorsal half of the 4th–6th lumbar spinal cord in a mouse model of spared nerve injury (SNI)-induced neuropathic pain. In-gel digests of the proteins size-separated on a polyacrylamide gel were subjected to reverse-phase liquid-chromatography coupled with electrospray ionization ion trap tandem mass spectrometry (MS/MS). After identifying proteins, the data were analyzed with subtractive proteomics usingProtAn, an in-house analytic program. Consequently, 15 downregulated and 35 upregulated proteins were identified in SNI mice. The identified proteins may contribute to the maintenance of neuropathic pain, and may provide new or valuable information in the discovery of new therapeutic targets for neuropathic pain.

Istamycin aminoglycosides profiling and their characterization in Streptomyces tenjimariensis ATCC 31603 culture using high‐performance liquid chromatography with tandem mass spectrometry

A high-performance liquid chromatography with electrospray ionization ion trap tandem mass spectrometry method was developed and validated for the robust profiling and characterization of biosynthetic congeners in the 2-deoxy-aminocyclitol istamycin pathway, from the fermentation broth of Streptomyces tenjimariensis ATCC 31603. Gradient elution on an Acquity CSH C18 column was performed with a gradient of 5mM aqueous pentafluoropropionic acid and 50% acetonitrile. Sixteen natural istamycin congeners were profiled and quantified in descending order; istamycin A, istamycin B, istamycin A0 , istamycin B0 , istamycin B1 , istamycin A1 , istamycin C, istamycin A2 , istamycin C1 , istamycin C0 , istamycin X0 , istamycin A3 , istamycin Y0 , istamycin B3 , and istamycin FU-10 plus istamycin AP. In addition, a total of five sets of 1- or 3-epimeric pairs were chromatographically separated using a macrocyclic glycopeptide-bonded chiral column. The lower limit of quantification of istamycin-A present in S. tenjimariensis fermentation was estimated to be 2.2ng/mL. The simultaneous identification of a wide range of 2-deoxy-aminocyclitol-type istamycin profiles from bacterial fermentation was determined for the first time by employing high-performance liquid chromatography with tandem mass spectrometry analysis and the separation of istamycin epimers.

Extraction and Analysis of Disperse Dyes from Colored Polyester Single Fibers Using Liquid Chromatography/Linear Ion Trap Tandem Mass Spectrometry.

Nine disperse dyes extracted from colored polyester threads and single fibers of manufactory-supplied textiles by using centrifugal filtration were analyzed using liquid chromatography/linear ion trap tandem mass spectrometry (LC/LIT-MS(n)). Based on diode array detector data, dimethylformamide (DMF) was found to be a more effective extraction solvent than acetonitrile/water (4:3, v/v) or methanol/water (1:1, v/v) mixtures. The precursor, [M+H](+) ions, were detected for the dyes extracted using DMF. The MS(2) and MS(3) spectra also matched those of the standard disperse dyes. Without relying on comparison clothes, disperse dyes extracted from the single fibers (5 mm in length) were successfully identified by LC/LIT-MS(n) and the custom-built database.

Metabolomic study of wild and cultivated caper (Capparis spinosa L.) from different areas of Sardinia and their comparative evaluation.

Capparis spinosa L. (Capparidaceae), also known as caper, is widely known for its very aromatic flower buds (capers),that are largely employed as a flavouring in cooking. Capparis species are regarded as a potential source of important bioactive compounds, in fact, due to their botanical relationship with Brassica species; they contain glucosinolates, secondary plant metabolites, that have been studied for their potential anticarcinogenic properties. In addition, the presence of other numerous beneficial compounds such as polyphenols, alkaloids, lipids, vitamins and minerals have been reported. The aim of this study was to individuate and determinate the principal bioactive compounds occurring in different part (leaves, buds and flowers) of wild and cultivated C. spinosa collected from different area of Sardinia (Italy). Ultra-high performance liquid chromatography-triple quadrupole/linear ion trap tandem mass spectrometry methods were used for identification and simultaneous determination of 27 bioactive molecules. Analysis of different samples revealed qualitative and quantitative differences in the content of flavonoids, glucosinolates, anthocyanins and phenolic acids. In particular, glucocapparin resulted the most abundant with values ranging from 112 to 364 mg/100 g Fresh Weight (FW); followed by rutin with highest value of 126 mg/100 g FW, 4-hydroxyglucobrassicin with highest value of 42 mg/100 g FW and isorhamnetin 3-O-rutinoside with highest value of 24 mg/100 g FW. Based on this metabolomic targeted approach, quantitative results were treated by principal component analysis to explore and visualise correlation and discrimination among collections of C. spinosa samples. Copyright © 2016 John Wiley & Sons, Ltd.

Electrospray ionization tandem mass spectrometric study of protonated and alkali- cationized α/ε-hybrid peptides: differentiation of a pair of dipeptide positional isomers.

A new class of Boc-N-protected hybrid peptides derived from L- Ala and ε6-Caa (L-Ala=L-Alanine, Caa=C-linked carboamino acid derived from D-xylose) have been studied by positive ion electrospray ionization (ESI) ion-trap tandem mass spectrometry (MS/MS). MSn spectra of protonated and alkali-cationized hybrid peptides produce characteristic fragmentation involving the peptide backbone, the tert-butyloxycarbonyl (Boc) group, and the side chain. The dipeptide positional isomers are differentiated by the collision-induced dissociation (CID) of the protonated and alkali-cationized peptides. The CID of [M+H]+ ion of Boc-NH-L-Ala-ε-Caa- OCH3 (1) shows a prominent [M+H-C4H8]+ ion, which is totally absent for its positional isomer Boc-NH-ε-Caa-L-Ala-OCH3 (6), which instead shows significant loss of t-butanol. The formation of the [M+Cat-C4H8]+ ion is totally absent and [M+Cat-Boc+H]+ is prominent in the CID of the [M+Cat]+ ion of Boc-NH-L-Ala-ε-Caa- OCH3 (1), whereas the former is highly abundant and the latter is of low abundance for its positional isomer Boc-NH-ε-Caa-L-Ala-OCH3 (6). It is observed that 'b' ions are abundant when oxazolone structures are formed through a five-membered cyclic transition state in tetra-, penta-, and hexapeptides and the cyclization process for larger 'b' ions led to an insignificant abundance. However, the significant 'b' ion is formed in ε,α-dipeptide, which may have a seven-membered substituted 2-oxoazepanium ion structure. The MSn spectra of [M+Cat-Boc+H]+ ions of these peptides are found to be significantly different to those of [M+H-Boc+H]+ ions. The CID spectra of [M+Cat-Boc+H]+ ions of peptide acids containing L-Ala at the C-terminus show an abundant N-terminal rearrangement ion, [bn+17+Cat]+, which is absent for the peptide acids containing ε-Caa at the C-terminus. Thus, the results of these hybrid peptides provide sequencing information, the structure of the cyclic intermediate involved in the formation of the rearrangement ion, and distinguish a pair of dipeptide positional isomers.

Application of a hybrid ordered mesoporous silica as sorbent for solid-phase multi-residue extraction of veterinary drugs in meat by ultra-high-performance liquid chromatography coupled to ion-trap tandem mass spectrometry

A quick, sensitive and selective analytical reversed-phase multi-residue method using ultra-high performance liquid chromatography coupled to an ion-trap mass spectrometry detector (UHPLC-IT-MS/MS) operating in both positive and negative ion mode was developed for the simultaneous determination of 23 veterinary drug residues (β-blockers, β-agonists and Non-Steroidal Anti-inflammatory Drugs (NSAIDs)) in meat samples. The sample treatment involved a liquid-solid extraction followed by a solid-phase extraction (SPE) procedure. SBA-15 type mesoporous silica was synthetized and modified with octadecylsilane, and the resulting hybrid material (denoted as SBA-15-C18) was applied and evaluated as SPE sorbent in the purification of samples. The materials were comprehensively characterized, and they showed a high surface area, high pore volume and a homogeneous distribution of the pores. Chromatographic conditions and extraction procedure were optimized, and the method was validated according to the Commission Decision 2002/657/EC. The method detection limits (MDLs) and the method quantification limits (MQLs) were determined for all the analytes in meat samples and found to range between 0.01–18.75μg/kg and 0.02–62.50μg/kg, respectively. Recoveries for 15 of the target analytes ranged from 71 to 98%. In addition, for comparative purpose SBA-15-C18 was evaluated towards commercial C18 amorphous silica. Results revealed that SBA-15-C18 was clearly more successful in the multi-residue extraction of the 23 mentioned analytes with higher recovery values. The method was successfully tested to analyze prepacked preparations of mince bovine meat. Traces of propranolol, ketoprofen and diclofenac were detected in some samples.

Metabolomic Profiles of Aspergillus oryzae and Bacillus amyloliquefaciens During Rice Koji Fermentation.

Rice koji, used early in the manufacturing process for many fermented foods, produces diverse metabolites and enzymes during fermentation. Using gas chromatography time-of-flight mass spectrometry (GC-TOF-MS), ultrahigh-performance liquid chromatography linear trap quadrupole ion trap tandem mass spectrometry (UHPLC-LTQ-IT-MS/MS), and multivariate analysis we generated the metabolite profiles of rice koji produced by fermentation with Aspergillus oryzae (RK_AO) or Bacillus amyloliquefaciens (RK_BA) for different durations. Two principal components of the metabolomic data distinguished the rice koji samples according to their fermenter species and fermentation time. Several enzymes secreted by the fermenter species, including α-amylase, protease, and β-glucosidase, were assayed to identify differences in expression levels. This approach revealed that carbohydrate metabolism, serine-derived amino acids, and fatty acids were associated with rice koji fermentation by A. oryzae, whereas aromatic and branched chain amino acids, flavonoids, and lysophospholipids were more typical in rice koji fermentation by B. amyloliquefaciens. Antioxidant activity was significantly higher for RK_BA than for RK_AO, as were the abundances of flavonoids, including tricin, tricin glycosides, apigenin glycosides, and chrysoeriol glycosides. In summary, we have used MS-based metabolomics and enzyme activity assays to evaluate the effects of using different microbial species and fermentation times on the nutritional profile of rice koji.

“Aroeira” (Myracrodruon urundeuva) methanol extract: the relationship between chemical compounds and cellular effects

Context: “Aroeira” [Myracrodruon urundeuva Allemão (Anacardiaceae)] is a tree whose leaves have been studied for therapeutic purposes in medicine and dentistry.Objective: The study chemically identifies the leaf extract of aroeira and determines its effect on human gingival fibroblasts.Materials and methods: An 80% methanol leave extract was obtained by maceration and chemically identified through flow-injection analysis–electrospray ionization–ion trap–tandem mass spectrometry (FIA–ESI–IT–MSn). Cytotoxicity of the aroeira’s methanol extract was evaluated in lineage of fibroblasts. Adherent cells were treated with different concentrations of aroeira’s methanol extract in the medium: 0.1, 1, 10, 100 and 1000 μg/mL. Control cells were cultivated in the medium only. Analyses were done at 24, 48, 72 and 96 h of culture by neutral red assay; and at 24, 48 and 96 h by crystal violet assay.Results: FIA–ESI–IT–MS analysis determined the presence of compounds, for the first time in the species: quercetin-O-glucuronide and quercetin-O-deoxyhexose-O-glucose in the extract. On one hand, neutral red and crystal violet assay showed a reduction (to 50% up until 100%) of cellular viability of groups of 100 and 1000 μg/mL compared with control at 96 h (p < 0.05). On the other hand, lower concentrations (0.1; 1 and 10 μg/mL) of the extract were similar to that of the control at 96 h (p < 0.05), in general.Conclusions: In view of the results, we can conclude that the extract of aroeira presents tannins and flavonoids. Furthermore, the extract is capable of modulating the viability of human gingival fibroblasts according to its concentration.

Identification and quantification of glucosinolates in Korean leaf mustard germplasm (Brassica juncea var. integrifolia) by liquid chromatography–electrospray ionization/tandem mass spectrometry

In the present investigation, glucosinolate content was identified and quantified in 210 accessions of Korean leaf mustard (Brassica juncea var. integrifolia) by a liquid chromatography (LC) with electrospray ionization (ESI) coupled with a positive-mode ion trap tandem mass spectrometry (LC–ESI–MS/MS). Eleven individual GSLs including two new compounds were identified in the accessions using desulfo-glucosinolates (DS-GSLs) LC–MS library, and they were elucidated by interpreting the fragmentation data ([M + H-glucose]+) obtained. The newly identified GSLs contained aliphatic and hydroxyl functional group in their back bone were named as 1-ethyl-2-hydroxyethyl DS-GSLs (glucosisautricin) or 2-hydroxy-2-methylpropyl DS-GSLs (glucoconringiin) and 3,4,5-trimethoxybenzyl DS-GSLs, respectively. Among all tested accessions, the total DS-GSLs content was found to be varied between 5.3 and 23.2 mg/g dry weight (DW) with an average of 13.0 mg/g DW in the germplasm. Each individual DS-GSLs component was found in decreasing order of sinigrin (41.7 %) >glucoiberverin (21.7 %) >gluconasturtiin (12.6 %) >glucobarbarin (10.0 %) >glucoiberin (5.1 %) >glucocheirolin (3.6 %) >glucobrassicanapin (2.6 %) >gluconapin (2.1 %), and >glucobrassicin (0.6 %). Interestingly, sinigrin and gluconasturtiin were present in higher content, and progoitrin was not detected significantly in the germplasm of Korean leaf mustard. In particular, accession K046197 (purple) was found to show highest total DS-GSL content (23.2 mg/g DW).