Fast Analysis of Taurine in Energetic Drinks by Electrospray Ionization Mass Spectrometry

Santos, LS (Santos, Leonardo S.). Univ Talca, Inst Quim Recursos Nat, Lab Asymmetr Synth, Talca, ChileDirect infusion electrospray ionization tandem mass spectrometry in the negative ion mode with single reaction monitoring is show to allow high selectivity and sensitivity in the quantification of taurine in energetic drinks. The method is also simple and rapid (less than 2 min run time), with high recovery and repeatability. Commercially available energetic drinks were found to contain taurine in concentrations quite different (lower or higher) from the declared amounts

Differentially expressed plasmatic microRNAs in Brazilian patients with Coronavirus disease 2019 (COVID-19): preliminary results

Background: Coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It is known that host microRNAs (miRNAs) can be modulated to favor viral infection or to protect the host. Herein, we report preliminary results of a study aiming at identifying differentially expressed plasmatic miRNAs in Brazilian patients with COVID-19. Methods and results: miRNAs were extracted from the plasma of eight patients with COVID-19 (four patients with mild COVID-19 and four patients with severe/critical COVID-19) and four healthy controls. Patients and controls were matched for sex and age. miRNA expression levels were detected using high-throughput sequencing. Differential miRNA expression and enrichment analyses were further evaluated. A total of 18 miRNAs were differentially expressed between patients with COVID-19 and controls. miR-4433b-5p, miR-6780b-3p, miR-6883-3p, miR-320b, miR-7111-3p, miR-4755-3p, miR-320c, and miR-6511a-3p were the most important miRNAs significantly involved in the PI3K/AKT, Wnt/β-catenin, and STAT3 signaling pathways. Moreover, 42 miRNAs were differentially expressed between severe/critical and mild patients with COVID-19. miR-451a, miR-101-3p, miR-185-5p, miR-30d-5p, miR-25-3p, miR-342-3p, miR-30e-5p, miR-150-5p, miR-15b-5p, and miR-29c-3p were the most important miRNAs significantly involved in the Wnt/β-catenin, NF-κβ, and STAT3 signaling pathways. Conclusions: If validated by quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) in a larger number of participants, the miRNAs identified in this study might be used as possible biomarkers for the diagnosis and severity of COVID-19

On-line monitoring of stevioside sweetener hydrolysis to steviol in acidic aqueous solutions

Santos, LS (reprint author), Talca Univ, Chem Inst Nat Resources, Lab Asymmetr Synth, POB 747, Talca, ChileStevioside, a potent sweetener obtained from leaves of Stevia rebaudiana (Bertoni), is the glycone of steviol. However, despite its natural origin, there has been concern about stevioside toxicity due to hydrolysis to the carcinogenic steviol. To approve it as an additive, the FAO/WHO committee on food additives has required further information about hydrolytic stability of the steviol glycoside in acidic foods and beverages. In this study, aqueous solutions of stevioside at different pH values were monitored in real time by direct infusion ESI-MS. Owing to the high speed and sensitivity of ESI-MS monitoring, fast hydrolysis of the stevioside molecule to steviol in aqueous acidic solutions was observed, particularly in acidic juices. (C) 2011 Elsevier Ltd. All rights reserved

Use Of Electrospray Ionization Mass Spectrometry To Fingerprint Beer

Mass spectrometry constitutes one of the most encompassing instrumental techniques in science, widely applied in the fi elds of chemistry, biology, medical science and technology. Direct insertion electrospray ionization mass spectrometry (ESI-MS) is a fast and sensitive method which differentiates diverse types of beer, in both positive and negative ion modes, characterizing their main constituents. Although the basic ingredients of beer (water, malt, hops and yeast) have not changed much since the dark ages, variations in these ingredients and in the manufacturing process result in diverse types of beer. The spectra or fi ngerprints of each type of beer permit not only the separation of samples according to their main characteristics, but also further information through the ESI-MS/MS fragmentation of the diagnostic ions of each type, adding another dimension to the analytical results. Fast and characteristic beer fi ngerprint mass spectra were obtained by ESI-MS in both the negative and positive modes. A total of 29 samples of ale produced in Brazil and other countries were divided into three groups by visual analysis of the positive [ESI(+)-MS] and negative [ESI(-)-MS] mode fi ngerprints as well as by chemometric analysis of the data. Many of the marker ions in both modes were found to be simple sugars and oligosaccharides, although their intensities varied depending on the type of ale (pale colored, dark colored and sweetened). This shows that direct infusion ESI-MS could distinguish between samples of ale with different compositions and is promising as a fast and effi cient method of beer characterization. © 2009 Elsevier Inc.923934Alcázar, A., Pablos, F., Martín, M.J., González, A.G., (2002) Talanta, 57, pp. 45-52Annesley, T.M., (2003) Clin. Chem., 49, pp. 1041-1044Araújo, A.S., Rocha, L.L.R., Tomazela, D.M., Sawaya, A.C.H.F., Almeida, R.R., Catharino, R.R., Eberlin, M.N., (2005) Analyst, 130, pp. 884-889Berlitz, H.D., Grosch, W., Schieberle, P., (2004) F ood Chemistry, , (3rd edn). Springer-Verlag, GermanyCatharino, R.R., Sawaya, A.C.H.F., Cunha, I.B.S., Fogaça, A.O., Facco, E.M.P., Godoy, H.T., Daudt, C.E., Eberlin, M.N., (2006) J. Mass Spectrom., 41, pp. 185-190Cole, R.B., (1997) Electrospray Ionization Mass Spectrometry, , John Wiley & Sons Inc., New YorkCole, R.B., (2000) J. Mass Spectrom., 35, pp. 763-772Cooks, R.G., Zhang, D.X., Koch, K.J., Gozzo, F.C., Eberlin, M.N., (2001) Anal. Chem., 73, pp. 3646-3655Degelmann, P., Becker, M., Herderich, M., Humpf, H.U., (1999) Chromatographia, 49, pp. 543-546Eberlin, M.N., Meurer, E., Santos, L.S., Pilli, R.A., (2003) Org. Lett., 5, pp. 1391-1394Gaumet, J.J., Strouse, G., (2000) J. Am. Soc. Mass Spectrom., 11, pp. 338-344Hans, X.L., Gross, R.W., (2001) A nalytic. Biochem., 265, pp. 88-100Hardwick, W.A., (1995) Handbook of Brewing, , Marcel Dekker, New YorkHofte, A.J.P., van der Hoeven, R.A.M., Fung, S.Y., Verpoorte, R., Tjaden, U.R., Van der Greef, J., (1998) J. Am. Soc. Brew. Chem., 56, pp. 118-122Klampfl, C.W., Himmelsbach, M., Buchberger, W., Klein, H., (2002) Anal. Chim. Acta, 454, pp. 185-191Koch, K.J., Gozzo, F.C., Nanita, S.C., Takats, Z., Eberlin, M.N., Cooks, R.G., (2002) Angew. Chem. Int. Ed. Engl., 41, p. 1721Kotiaho, T., Eberlin, M.N., Vainiotalo, P., Kostiainen, R., (2000) J. Am. Soc. Mass Spectrom., 11, pp. 526-535Mauri, P., Minoggio, M., Simonetti, P., Gardana, C., Pietta, P., (2002) Rapid Commun. Mass Spectrom., 16, pp. 743-748Möller, J.K., Catharino, R.R., Eberlin, M.N., (2005) Analyst, 130, pp. 890-897de la Mora, J.F., Berkel, G.J.V., Enke, C.G., Cole, R.B., Sanchez, M.M., Fenn, J.B., (2000) J. Mass Spectrom., 35, pp. 939-952Raftery, M.J., Geczy, C.L.J., (2002) J. Am. Soc Mass Spectrom., 13, pp. 709-718Rioli, V., Gozzo, F.C., Shida, C.S., Krieger, J.E., Heimann, A.S., Linardi, A., Almeida, P.C., Ferro, E.S., (2003) J. Biol. Chem., 278, pp. 8547-8555Russel, D.H., (1994) Experimental Mass Spectrometry, , Plenum Press, New YorkSawaya, A.C.H.F., Tomazela, D.M., Cunha, I.B.S., Bankova, V.S., Marcucci, M.C., Custódio, A.R., Eberlin, M.N., (2004) Analyst, 129, pp. 739-744Schoonjans, V., Taylor, N., Hudson, B.D., Massart, D.L., (2002) J. Pharm. Biomed. Anal., 28, pp. 537-548Siuzdak, G., (2005) An Introduction to Mass Spectrometry Ionization: An Excerpt from the Expanding Role of Mass Spectrometry in Biotechnology, , 2nd edn. MCC Press, San Diego, CAWhittle, N., Eldridge, H., Bartley, J., Organ, G., (1999) J. Inst. Brew., 105, pp. 89-99Williams, J.D., Flanagan, M., Lopez, L., Fischer, S., Miller, L.A.D., (2003) J. Chromatogr. A., 1020, pp. 11-26Zhang, X.R., Minear, R.A., Guo, Y.B., Hwang, C.J., Barret, S.E., Ikeda, K., Shimizu, Y., Matsui, S., (2004) W ater Res., 38, pp. 3920-393