PubMed

Related Articles Multiple levels of regulation determine monoterpenoid essential oil compositional variation in the mint family. Mol Plant. 2015 Jan;8(1):188-91 Authors: Ahkami A, Johnson SR, Srividya N, Lange BM PMID: 25578282 [PubMed - indexed for MEDLINE]

Related Articles Polyunsaturated fatty acid metabolites as novel lipidomic biomarkers for noninvasive diagnosis of nonalcoholic steatohepatitis. J Lipid Res. 2015 Jan;56(1):185-92 Authors: Loomba R, Quehenberger O, Armando A, Dennis EA Abstract Lipotoxicity is a key mechanism thought to be responsible for the progression of nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH). Noninvasive diagnosis of NASH is a major unmet clinical need, and we hypothesized that PUFA metabolites, in particular arachidonic acid (AA)-derived eicosanoids, in plasma would differentiate patients with NAFL from those with NASH. Therefore, we aimed to assess the differences in the plasma eicosanoid lipidomic profile between patients with biopsy-proven NAFL versus NASH versus normal controls without nonalcoholic fatty liver disease (NAFLD; based on MRI fat fraction <5%). We carried out a cross-sectional analysis of a prospective nested case-control study including 10 patients with biopsy-proven NAFL, 9 patients with biopsy-proven NASH, and 10 non-NAFLD MRI-phenotyped normal controls. We quantitatively compared plasma eicosanoid and other PUFA metabolite levels between NAFL versus NASH versus normal controls. Utilizing a uniquely well-characterized cohort, we demonstrated that plasma eicosanoid and other PUFA metabolite profiling can differentiate between NAFL and NASH. The top candidate as a single biomarker for differentiating NAFL from NASH was 11,12-dihydroxy-eicosatrienoic acid (11,12-diHETrE) with an area under the receiver operating characteristic curve (AUROC) of 1. In addition, we also found a panel including 13,14-dihydro-15-keto prostaglandin D2 (dhk PGD2) and 20-carboxy arachidonic acid (20-COOH AA) that demonstrated an AUROC of 1. This proof-of-concept study provides early evidence that 11,12-diHETrE, dhk PGD2, and 20-COOH AA are the leading eicosanoid candidate biomarkers for the noninvasive diagnosis of NASH. PMID: 25404585 [PubMed - indexed for MEDLINE]

Related Articles Enhanced formation of aromatic amino acids increases fragrance without affecting flower longevity or pigmentation in Petunia × hybrida. Plant Biotechnol J. 2015 Jan;13(1):125-36 Authors: Oliva M, Ovadia R, Perl A, Bar E, Lewinsohn E, Galili G, Oren-Shamir M Abstract Purple Petunia × hybrida V26 plants accumulate fragrant benzenoid-phenylpropanoid molecules and anthocyanin pigments in their petals. These specialized metabolites are synthesized mainly from the aromatic amino acids phenylalanine. Here, we studied the profile of secondary metabolites of petunia plants, expressing a feedback-insensitive bacterial form of 3-deoxy-di-arabino-heptulosonate 7-phosphate synthase enzyme (AroG*) of the shikimate pathway, as a tool to stimulate the conversion of primary to secondary metabolism via the aromatic amino acids. We focused on specialized metabolites contributing to flower showy traits. The presence of AroG* protein led to increased aromatic amino acid levels in the leaves and high phenylalanine levels in the petals. In addition, the AroG* petals accumulated significantly higher levels of fragrant benzenoid-phenylpropanoid volatiles, without affecting the flowers' lifetime. In contrast, AroG* abundance had no effect on flavonoids and anthocyanins levels. The metabolic profile of all five AroG* lines was comparable, even though two lines produced the transgene in the leaves, but not in the petals. This implies that phenylalanine produced in leaves can be transported through the stem to the flowers and serve as a precursor for formation of fragrant metabolites. Dipping cut petunia stems in labelled phenylalanine solution resulted in production of labelled fragrant volatiles in the flowers. This study emphasizes further the potential of this metabolic engineering approach to stimulate the production of specialized metabolites and enhance the quality of various plant organs. Furthermore, transformation of vegetative tissues with AroG* is sufficient for induced production of specialized metabolites in organs such as the flowers. PMID: 25283446 [PubMed - indexed for MEDLINE]

Related Articles [Mechanism research on the lupeol treatment on MCF-7 breast cancer cells based on cell metabonomics]. Se Pu. 2014 Mar;32(3):278-83 Authors: Shi D, Kuang Y, Wang G, Peng Z, Wang Y, Yan C Abstract The objective of this research is to investigate the suppressive effects of lupeol on MCF-7 breast cancer cells, and explore its mechanism on inhibiting the proliferation of MCF-7 cells based on cell metabonomics and cell cycle. Gas chromatography-mass spectrometry (GC-MS) was used in the cell metabonomics assay to identify metabolites of MCF-7 cells and MCF-7 cells treated with lupeol. Then, orthogonal partial least squares discriminant analysis (OPLS-DA) was used to process the metabolic data and model parameters of OPLS-DA were as follows: R2Ycum = 0.988, Q2Ycum = 0.964, which indicated that these two groups could be distinguished clearly. The metabolites (VIP (variable importance in the projection) > 1) were analyzed by t-test, and finally, metabolites (t < 0.05) were identified to be biomarkers. Eleven metabolites such as butanedioic acid, phosphoric acid, L-leucine and isoleucine which had a significant contribution to classification were selected and preliminarily identified due to the accurate mass. Cell cycle assay was analyzed by FACSCalibur. Since the cells in the phase of G1 were increased significantly after the treatment of lupeol, we speculated that lupeol has a blocking effect on the generation of succinyl-CoA and the reaction of substrate phosphorylation of tricarboxylic acid cycle of MCF-7 cells. This study provided a novel approach to the mechanism research on the lupeol treatment on MCF-7 breast cancer cells based on cell metabonomics. PMID: 24984468 [PubMed - indexed for MEDLINE]

25 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2015/09/01PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Related Articles Escher: A Web Application for Building, Sharing, and Embedding Data-Rich Visualizations of Biological Pathways. PLoS Comput Biol. 2015 Aug;11(8):e1004321 Authors: King ZA, Dräger A, Ebrahim A, Sonnenschein N, Lewis NE, Palsson BO Abstract Escher is a web application for visualizing data on biological pathways. Three key features make Escher a uniquely effective tool for pathway visualization. First, users can rapidly design new pathway maps. Escher provides pathway suggestions based on user data and genome-scale models, so users can draw pathways in a semi-automated way. Second, users can visualize data related to genes or proteins on the associated reactions and pathways, using rules that define which enzymes catalyze each reaction. Thus, users can identify trends in common genomic data types (e.g. RNA-Seq, proteomics, ChIP)-in conjunction with metabolite- and reaction-oriented data types (e.g. metabolomics, fluxomics). Third, Escher harnesses the strengths of web technologies (SVG, D3, developer tools) so that visualizations can be rapidly adapted, extended, shared, and embedded. This paper provides examples of each of these features and explains how the development approach used for Escher can be used to guide the development of future visualization tools. PMID: 26313928 [PubMed - as supplied by publisher]

Related Articles How should we choose the 'best' embryo? A commentary on behalf of the British Fertility Society and the Association of Clinical Embryologists. Hum Fertil (Camb). 2015 Aug 27;:1-9 Authors: Bolton VN, Leary C, Harbottle S, Cutting R, Harper JC Abstract Embryo selection to improve pregnancy rates remains a significant challenge in IVF. Non-invasive and invasive methods of embryo selection include morphological assessment, metabolomics, time-lapse imaging and preimplantation genetic screening. To date, none has been shown conclusively to yield improved implantation and live birth rates. This review summarises current understanding of methods for embryo selection. PMID: 26313607 [PubMed - as supplied by publisher]

Related Articles Direct metabolomics for plant cells by live single-cell mass spectrometry. Nat Protoc. 2015 Sep;10(9):1445-1456 Authors: Fujii T, Matsuda S, Tejedor ML, Esaki T, Sakane I, Mizuno H, Tsuyama N, Masujima T Abstract Live single-cell mass spectrometry (live MS) provides a mass spectrum that shows thousands of metabolite peaks from a single live plant cell within minutes. By using an optical microscope, a cell is chosen for analysis and a metal-coated nanospray microcapillary tip is used to remove the cell's contents. After adding a microliter of ionization solvent to the opposite end of the tip, the trapped contents are directly fed into the mass spectrometer by applying a high voltage between the tip and the inlet port of the spectrometer to induce nanospray ionization. Proteins are not detected because of insufficient sensitivity. Metabolite peaks are identified by exact mass or tandem mass spectrometry (MS/MS) analysis, and isomers can be separated by combining live MS with ion-mobility separation. By using this approach, spectra can be acquired in 10 min. In combination with metabolic maps and/or molecular databases, the data can be annotated into metabolic pathways; the data analysis takes 30 min to 4 h, depending on the MS/MS data availability from databases. This method enables the analysis of a number of metabolites from a single cell with rapid sampling at sub-attomolar-level sensitivity. PMID: 26313480 [PubMed - as supplied by publisher]

Related Articles Investigating a signature of temozolomide resistance in GBM cell lines using metabolomics. J Neurooncol. 2015 Aug 28; Authors: St-Coeur PD, Poitras JJ, Cuperlovic-Culf M, Touaibia M, Morin PJ Abstract Glioblastoma multiforme (GBM) is the most common form of malignant glioma. Current therapeutic approach to treat this malignancy involves a combination of surgery, radiotherapy and chemotherapy with temozolomide. Numerous mechanisms contributing to inherent and acquired resistance to this chemotherapeutic agent have been identified and can lead to treatment failure. This study undertook a metabolomics-based approach to characterize the metabolic profiles observed in temozolomide-sensitive and temozolomide-resistant GBM cell lines as well as in a small sub-set of primary GBM tumors. This approach was also utilized to explore the metabolic changes modulated upon cell treatment with temozolomide and lomeguatrib, an MGMT inhibitor with temozolomide-sensitizing potential. Metabolites previously explored for their potential role in chemoresistance including glucose, citrate and isocitrate demonstrated elevated levels in temozolomide-resistant GBM cells. In addition, a signature of metabolites comprising alanine, choline, creatine and phosphorylcholine was identified as up-regulated in sensitive GBM cell line across different treatments. These results present the metabolic profiles associated with temozolomide response in selected GBM models and propose interesting leads that could be leveraged for the development of therapeutic or diagnostic tools to impact temozolomide response in GBMs. PMID: 26311249 [PubMed - as supplied by publisher]

Related Articles NMR-based metabolomic urinalysis: a rapid screening test for urinary tract infection. Clin Chim Acta. 2014 Sep 25;436:217-23 Authors: Lam CW, Law CY, To KK, Cheung SK, Lee KC, Sze KH, Leung KF, Yuen KY Abstract BACKGROUND: Urinary tract infection (UTI) is one of the most common bacterial infections in humans; however, there is no accurate and fast quantitative test to detect UTI. Dipstick urinalysis is semi-quantitative with a limited diagnostic accuracy, while urine culture is accurate but takes time. We described a quantitative biochemical method for the diagnosis of bacteriuria using a single marker. METHODS: We compared the urine metabolomes from 88 patients with bacterial UTI and 61 controls using (1)H NMR spectroscopy followed by principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA). The biomarker identified was subsequently validated using independent samples. RESULTS: The urine acetic acid/creatinine (mmol/mmol) level was determined to be the most discriminatory marker for bacterial UTI with an area-under-receiver operating characteristic curve=0.97, sensitivity=91% and specificity=95% at the optimal cutoff 0.03 mmol/mmol. For validation, 60 samples were recruited prospectively. Using the optimal cutoff for acetic acid/creatinine, this method showed sensitivity=96%, specificity=94%, positive predictive value=92%, negative predictive value=97% and an overall accuracy=95%. The diagnostic performance was superior to dipstick urinalysis or microscopy. In addition, we also observed an increase of urinary trimethylamine (TMA) in patients with Escherichia coli-associated UTI. TMA is a mammalian-microbial co-metabolite and the high level of TMA generated is related to the bacterial enzyme, trimethylamine N-oxide (TMAO) reductase which reduces TMAO to TMA. CONCLUSIONS: Urine acetic acid is a neglected metabolite that can be used for rapid diagnosis of UTI and TMA can be used for etiologic diagnosis of UTI. With the introduction of NMR-based clinical analyzers to clinical laboratories, NMR-based urinalysis can be translated for clinical use. PMID: 24909875 [PubMed - indexed for MEDLINE]

Related Articles Automated quantum mechanical total line shape fitting model for quantitative NMR-based profiling of human serum metabolites. Anal Bioanal Chem. 2014 May;406(13):3091-102 Authors: Mihaleva VV, Korhonen SP, van Duynhoven J, Niemitz M, Vervoort J, Jacobs DM Abstract An automated quantum mechanical total line shape (QMTLS) fitting model was implemented for quantitative nuclear magnetic resonance (NMR)-based profiling of 42 metabolites in ultrafiltrated human serum samples. Each metabolite was described by a set of chemical shifts, J-couplings, and line widths. These parameters were optimized for each metabolite in each sample by iteratively minimizing the difference between the calculated and the experimental spectrum. In total, 92.0 to 98.1 % of the signal intensities in the experimental spectrum could be explained by the calculated spectrum. The model was validated by comparison to signal integration of metabolites with isolated signals and by means of standard additions. Metabolites present at average concentration higher than 50 μM were quantified with average absolute relative error less than 10 % when using different initial parameters for the fitting procedure. Furthermore, the biological applicability of the QMTLS model was demonstrated on 287 samples from an intervention study in 37 human volunteers undergoing an exercise challenge. Our automated QMTLS model was able to cope with the large dynamic range of metabolite concentrations in serum and proved to be suitable for high-throughput analysis. PMID: 24722875 [PubMed - indexed for MEDLINE]

Rapid and noninvasive technique to assess the metabolomics profile of bovine embryos produced in vitro by Raman spectroscopy. Biomed Opt Express. 2015 Aug 1;6(8):2830-2839 Authors: Santos EC, Martinho HS, Annes K, Leite RF, Milazzotto MP Abstract Morphological assessments are used to select embryos with the highest implantation potential, however it is still very limited. The development of new technologies, such as Raman spectroscopy have improved quantitative and qualitative analysis, and consequently led to a better characterization of embryos and improvements on the prediction of their potential. Therefore, we propose a method based on the conventional in vitro culture system of bovine embryos, and the subsequent analysis of the culture media drops by Raman spectroscopy. Our results obtained by PCA analysis clearly showed a separation of the spectral profiles from culture media drops with and without embryos. PMID: 26309747 [PubMed - as supplied by publisher]

Alterations of plasma metabolite profiles related to adipose tissue distribution and cardiometabolic risk. Am J Physiol Endocrinol Metab. 2015 Aug 25;:ajpendo.00231.2015 Authors: Boulet MM, Chevrier G, Grenier-Larouche T, Pelletier M, Nadeau M, Scarpa J, Prehn C, Marette A, Adamski J, Tchernof A Abstract CONTEXT: Metabolomic profiling of obese individuals revealed altered concentrations of many metabolites, especially branched-chain amino acids (BCAA), possibly linked to altered adipose tissue BCAA catabolism. OBJECTIVE: We tested the hypothesis that some features of this metabolite signature relate closely to visceral obesity and concomitant alterations in cardiometabolic risk factors. We also postulated that alterations in BCAA-catabolizing enzymes are predominant in visceral adipose tissue. METHODS: Fifty-nine women (BMI 20-41 kg/m(2)) undergoing gynecologic surgery were recruited and characterized for overall and regional adiposity, blood metabolite levels using targeted metabolomics and cardiometabolic risk factors. Adipose samples (visceral and subcutaneous) were obtained and used for gene expression and western blot analyses. RESULTS: Obese women had significantly higher circulating BCAA and Kynurenine/Tryptophan (KYN/Trp) ratio than lean or overweight women (p<0.01). Principal component analysis confirmed that factors related to AA and the KYN/Trp ratio were positively associated with BMI, fat mass, visceral or subcutaneous adipose tissue area and subcutaneous adipocyte size (p≤0.05). AA-related factor was positively associated with HOMA-IR (p≤0.01). Factors reflecting glycerophospholipids and sphingolipids levels were mostly associated with altered blood lipid concentrations (p≤0.05). Glutamate level was the strongest independent predictor of visceral adipose tissue area (r=0.46, p<0.001). Obese women had lower expression and protein levels of BCAA-catabolizing enzymes in visceral adipose tissue compared to overweight or lean women (p≤0.05). CONCLUSIONS: Among metabolites altered in obesity, plasma concentrations of BCAA and the KYN/Trp ratio are closely related to increased adiposity. Alterations in expression and protein levels of BCAA-catabolizing enzymes are predominant in visceral adipose tissue. PMID: 26306599 [PubMed - as supplied by publisher]

Related Articles Low- and high-grade bladder cancer appraisal via serum-based proteomics approach. Clin Chim Acta. 2014 Sep 25;436:97-103 Authors: Bansal N, Gupta A, Sankhwar SN, Mahdi AA Abstract OBJECTIVE: To address the shortcomings of urine cytology and cystoscopy for screening and grading of urinary bladder cancer (BC) we applied a serum-based proteomics approach as a surrogate tactic for rapid BC probing. METHODS: This study was performed on 90 sera samples comprising of low-grade (LG, n=33) and high-grade (HG, n=32) BC, and healthy controls (HC, n=25). Two-dimensional gel electrophoresis (2DE) tactic was executed to describe serum proteome. MALDI-TOF-MS (MS) was used to identify the characteristics of aberrantly expressed proteins in 2DE and validated using Western blot (WB) and ELISA approach. Receiver operating characteristics (ROC) curve analysis was also performed to determine the clinical usefulness of these proteins to discriminate among LG, HG and HC cohorts. RESULTS: This comprehensive approach of 2DE, MS, WB and ELISA reveals five differentially expressed proteins. Among them two biomarkers (S100A8 and S100A9) were able to accurately (ROC, 0.946) distinguish 81% of BC (LG+HG) cases compared to HC with highest sensitivity and specificity. With a comparable tactic, two biomarkers (S100A8 and S100A4) were able to precisely (ROC, 0.941) discriminate 92% of LG cases from HG with utmost sensitivity and specificity. CONCLUSIONS: Serum proteomics probing appears to be an encouraging and least-invasive tactic for screening and grading of BC. PMID: 24875752 [PubMed - indexed for MEDLINE]

Oligoribonuclease is a central feature of cyclic diguanylate signaling in Pseudomonas aeruginosa. Proc Natl Acad Sci U S A. 2015 Aug 24; Authors: Cohen D, Mechold U, Nevenzal H, Yarmiyhu Y, Randall TE, Bay DC, Rich JD, Parsek MR, Kaever V, Harrison JJ, Banin E Abstract The second messenger cyclic diguanylate (c-di-GMP) controls diverse cellular processes among bacteria. Diguanylate cyclases synthesize c-di-GMP, whereas it is degraded by c-di-GMP-specific phosphodiesterases (PDEs). Nearly 80% of these PDEs are predicted to depend on the catalytic function of glutamate-alanine-leucine (EAL) domains, which hydrolyze a single phosphodiester group in c-di-GMP to produce 5'-phosphoguanylyl-(3',5')-guanosine (pGpG). However, to degrade pGpG and prevent its accumulation, bacterial cells require an additional nuclease, the identity of which remains unknown. Here we identify oligoribonuclease (Orn)-a 3'→5' exonuclease highly conserved among Actinobacteria, Beta-, Delta- and Gammaproteobacteria-as the primary enzyme responsible for pGpG degradation in Pseudomonas aeruginosa cells. We found that a P. aeruginosa Δorn mutant had high intracellular c-di-GMP levels, causing this strain to overexpress extracellular polymers and overproduce biofilm. Although recombinant Orn degraded small RNAs in vitro, this enzyme had a proclivity for degrading RNA oligomers comprised of two to five nucleotides (nanoRNAs), including pGpG. Corresponding with this activity, Δorn cells possessed highly elevated pGpG levels. We found that pGpG reduced the rate of c-di-GMP degradation in cell lysates and inhibited the activity of EAL-dependent PDEs (PA2133, PvrR, and purified recombinant RocR) from P. aeruginosa. This pGpG-dependent inhibition was alleviated by the addition of Orn. These data suggest that elevated levels of pGpG exert product inhibition on EAL-dependent PDEs, thereby increasing intracellular c-di-GMP in Δorn cells. Thus, we propose that Orn provides homeostatic control of intracellular pGpG under native physiological conditions and that this activity is fundamental to c-di-GMP signal transduction. PMID: 26305928 [PubMed - as supplied by publisher]

Metabolic footprint of epiphytic bacteria on Arabidopsis thaliana leaves. ISME J. 2015 Aug 25; Authors: Ryffel F, Helfrich EJ, Kiefer P, Peyriga L, Portais JC, Piel J, Vorholt JA Abstract The phyllosphere, which is defined as the parts of terrestrial plants above the ground, is a large habitat for different microorganisms that show a high extent of adaption to their environment. A number of hypotheses were generated by culture-independent functional genomics studies to explain the competitiveness of specialized bacteria in the phyllosphere. In contrast, in situ data at the metabolome level as a function of bacterial colonization are lacking. Here, we aimed to obtain new insights into the metabolic interplay between host and epiphytes upon colonization of Arabidopsis thaliana leaves in a controlled laboratory setting using environmental metabolomics approaches. Quantitative nuclear magnetic resonance (NMR) and imaging high-resolution mass spectrometry (IMS) methods were used to identify Arabidopsis leaf surface compounds and their possible involvement in the epiphytic lifestyle by relative changes in compound pools. The dominant carbohydrates on the leaf surfaces were sucrose, fructose and glucose. These sugars were significantly and specifically altered after epiphytic leaf colonization by the organoheterotroph Sphingomonas melonis or the phytopathogen Pseudomonas syringae pv. tomato, but only to a minor extent by the methylotroph Methylobacterium extorquens. In addition to carbohydrates, IMS revealed surprising alterations in arginine metabolism and phytoalexin biosynthesis that were dependent on the presence of bacteria, which might reflect the consequences of bacterial activity and the recognition of not only pathogens but also commensals by the plant. These results highlight the power of environmental metabolomics to aid in elucidating the molecular basis underlying plant-epiphyte interactions in situ. PMID: 26305156 [PubMed - as supplied by publisher]

Evolution of metabolomics profile of crab paste during fermentation. Food Chem. 2016 Feb 1;192:886-92 Authors: Chen D, Ye Y, Chen J, Yan X Abstract Crab paste is regularly consumed by people in the coastal area of China. The fermentation time plays a key role on the quality of crab paste. Here, we investigated the dynamic evolution of metabolite profile of crab paste during fermentation by combined use of NMR spectroscopy and multivariate data analysis. Our results showed that crab paste quality was significantly affected by fermentation. The quality change was manifested in the decline of lactate, betaine, taurine, trimethylamine-N-oxide, trigonelline, inosine, adenosine diphosphate, and 2-pyridinemethanol, and in the fluctuation of a range of amino acids as well as in the accumulation of glutamate, sucrose, formate, acetate, trimethylamine, and hypoxanthine. Trimethylamine production and its increased level with fermentation could be considered as a freshness index of crab paste. These results contribute to quality assessment of crab paste and confirm the metabolomics technique as a useful tool to provide important information on the crab paste quality. PMID: 26304425 [PubMed - in process]

Metabolomics and microbiological profile of Italian mozzarella cheese produced with buffalo and cow milk. Food Chem. 2016 Feb 1;192:618-24 Authors: Pisano MB, Scano P, Murgia A, Cosentino S, Caboni P Abstract Italian buffalo mozzarella (BM) cheese metabolite profile and microbial communities were characterised and compared to cow mozzarella (CM). Polar metabolite profiles were studied by gas-chromatography mass-spectrometry (GC-MS) and results elaborated by multivariate analysis (MVA). BM produced using natural whey starter cultures (NWS) exhibited a higher microbial diversity with less psychrotrophic bacteria. BM samples were higher in threonine, serine, valine, and lower in orotic acid and urea. CM produced with commercial starters (CMS) had the highest count of Streptococcus thermophilus and higher levels of galactose and phenylalanine. CM obtained by direct acidification (CMA) had lower microbial counts and higher levels of urea and sugars. Orotic acid was the only metabolite linked to milk animal origin. Results indicated that this metabolite pool well reflects the different production protocols and microbial complexity of these dairy products. This approach can help to protect the designation of origin of Italian buffalo mozzarella. PMID: 26304391 [PubMed - in process]

Global metabolite profiling and diagnostic ion filtering strategy by LC-QTOF MS for rapid identification of raw and processed pieces of Rheum palmatum L. Food Chem. 2016 Feb 1;192:531-40 Authors: Liu Y, Li L, Xiao YQ, Yao JQ, Li PY, Yu DR, Ma YL Abstract Due to its variety of functions, rhubarb has been used for thousands of years in many countries. It is commonly used after processing. Processing usually affect the chemical profile and the contents of active compounds in herbals, leading to changes of their bioactivities. Here, an approach of metabolite profiling and diagnostic ion filtering strategy with liquid chromatography-quadrupole/time-of-flight mass spectrometry was established for rapid identification of raw and processed pieces of Rheum palmatum L. (RPL). The comprehensive and unbiased information of 30 batches of RPL covering raw and two general processing methods were given by metabolomic profiles. Using molecular feature extraction algorithm, non-targeted compounds were analyzed in minutes. In total, 73 characteristic markers were extracted and identified by diagnostic ion filtering. They have been further analyzed by partial least squares-support vector machine-based pattern recognition. The comprehensive and rapid method for raw and processed pieces of RPL classification shows good sensitivity, specificity and prediction performance. PMID: 26304381 [PubMed - in process]

Sulfur dioxide residue in sulfur-fumigated edible herbs: The fewer, the safer? Food Chem. 2016 Feb 1;192:119-24 Authors: Duan SM, Xu J, Bai YJ, Ding Y, Kong M, Liu HH, Li XY, Zhang QS, Chen HB, Liu LF, Li SL Abstract The residual content of sulfur dioxide is frequently regarded as the exclusive indicator in the safety evaluation of sulfur-fumigated edible herbs. To examine the feasibility of such assessment criteria, here the variations in residual sulfur dioxide content during sulfur-fumigation and the potential mechanisms involved were investigated, using Angelicae Sinensis Radix (ASR) as a model herb. The residual sulfur dioxide content and ten major bioactive components in sulfur-fumigated ASR samples were dynamically examined at 13 successive time points within 72h sulfur-fumigation. The relationship between the content variation tendency of sulfur dioxide and the ten chemicals was discussed. The results suggested that sulfur dioxide-involved chemical transformation of the original components in ASR might cause large consumption of residual sulfur dioxide during sulfur-fumigation. It implies that without considering the induced chemical transformation of bioactive components, the residual sulfur dioxide content alone might be inadequate to comprehensively evaluate the safety of sulfur-fumigated herbs. PMID: 26304328 [PubMed - in process]