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Fast Analysis of Taurine in Energetic Drinks by Electrospray Ionization Mass Sp...
Catharino,Rodrigo R.; Haddad,Renato; Godoy,Helena T.; Eberlin,Marcos N.; Santos,Leonardo S.Direct 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 concentration...
Antioxidant activity and composition of propolis obtained by different methods ...
Cottica,Solange M; Sawaya,Alexandra C. H. F; Eberlin,Marcos N; Franco,Selma L; Zeoula,Lucia M; Visentainer,Jesuí VEthanolic extracts of propolis obtained with different concentrations of propolis and made using hydrous ethanol with various water/ethanol contents were analyzed. The antioxidant action of the extracts was determined by free radical 1,1-diphenyl-2-picryl-hydrazyl (DPPH·) scavenging and by ferric reducing ability power (FRAP), using the ferric-tripyridyl triazine (Fe3+-TPTZ) complex. The total phenolic and flav...
Monitoring of β-blockers ozone degradation via electrospray ionization mas...
Quispe,Cristina; Nachtigall,Fabiane M; Fonseca,Maria Francesca R; Alberici,Rosana M; Astudillo,Luis; Villaseñor,Jorge; Eberlin,Marcos NThe structures of intermediate products of ozone degradation of different pharmaceutical compounds have been studied. Under the conditions employed, complete ozone degradation of nadolol was achieved after 100 min. The degradation products obtained in aqueous solution were characterized by electrospray ionization mass (and tandem mass) spectrometry (ESI-MS and ESI-MS/MS). The proposed mechanism for degradation,...
Citocalasinas produzidas por Xylaria sp., um fungo endofítico de Piper aduncum ...
Silva,Geraldo H.; Oliveira,Camila M. de; Teles,Helder L.; Bolzani,Vanderlan da S.; Araujo,Angela R.; Pfenning,Ludwig H.; Young,Maria Claudia M.A chemical study on the EtOAc extract produced by Xylaria sp., an endophytic fungus from Piper aduncum, resulted in the isolation of a new cytochalasin 1, along with five known 19,20-epoxycytochalasin D (2), C (3), N (4), Q (5), and R (6). The 1-6 were evaluated against the fungi C. cladosporioides and C. sphaerospermum and only 5 showed weak activity. The cytotoxicity in vitro against HeLA and CHO cells lines ...
Other chemical constituents isolated from Solanum crinitum Lam. (Solanaceae)
Cornelius,Marli T. F.; Carvalho,Mário G. de; Silva,Tania M. S. da; Alves,Cassia C. F.; Siston,Ana P. N.; Alves,Kelly Z.; Sant'Anna,Carlos M. R.The phytochemical investigation of Solanum crinitum Lam led to the isolation from the fruit trichomes of four flavonoids, tiliroside (1), astragalin (2), kaempferol (3), biochanin A-7-O-β-D-apiofuranosyl-(1→5)-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside (7), along with 4-hydroxybenzoic acid (12), and four cinnamic acid derivatives, cis- and trans- coumaric acids (10 and 11) and cis- a...
Green and roasted arabica coffees differentiated by ripeness, process and cup q...
Amorim,Ana Carolina L.; Hovell,Ana Maria C.; Pinto,Angelo C.; Eberlin,Marcos N.; Arruda,Neusa P.; Pereira,Elenilda J.; Bizzo,Humberto R.Direct infusion electrospray ionization mass spectrometry in both the negative ESI(-)-MS and positive ESI(+)-MS ion modes are investigated to differentiate green and roasted Arabica coffees with different stages of ripeness (green, ripe and overripe), post-harvesting process (dry, wet and semi-wet) and coffees with different cup qualities. In the ESI(-)-MS of green coffees, ions from deprotonated fatty acids an...
A new polyacetylene from Vernonia scorpioides (Lam.) Pers. (Asteraceae) and its...
Buskuhl,Humberto; Freitas,Rilton A.; Monache,Franco Delle; Barison,Andersson; Campos,Francinete R.; Corilo,Yuri E.; Eberlin,Marcos N.The dichloromethane fraction obtained from hydroalcoholic crude extract of leaves and flowers of Vernonia scorpioides (Asteraceae) was investigated, resulting in the isolation and structure elucidation of a new polyacetylene namely 5-octa-2,4,6-triynyl-furan-2(5H)-one. The structure of the isolated compound was determined based on IR, NMR (1D and 2D) and MS spectrometric data. The antitumor potential, including...
Tri-n-butyltin Hydride-Mediated radical reactions of ortho-and meta-Iodobenzami...
Faraco,Renata F. P.; Oliveira,Grazielli C. B. de; Pinto,Gleydson D.; Rocha,Ana P. C.; Alves,Ricardo J.; Alves,Rosemeire B.; Abdelnur,Patrícia V.Reactions of methyl 4-O-allyl-2,3-di-O-benzyl-6-deoxy-6-(3-iodobenzoylamino)-α-D-galactopyranoside, its gluco epimer, methyl 2,3-di-O-benzyl-6-deoxy-6-(3-iodobenzoylamino)-4-O-(1-pentenyl)-α-D-glucopyranoside and its ortho-regioisomer with tri-n-butyltin hydride were performed in different conditions. Depending on reaction conditions the three meta-iodo isomers gave a surprising amount of biphenyl com...
Chloroform formation by chlorination of aqueous algae suspensions: online monit...
Borges,João T.; Sparrapan,Regina; Guimarães,José R.; Eberlin,Marcos N.; Augusti,RodineiMembrane introduction mass spectrometry (MIMS) was used to perform on-line monitoring of the chloroform formation via the chlorination of aqueous suspensions of several green and blue-green Brazilian algae (Microcystis panniformis, Selenastrum sp., Scenedesmus sp., Monoraphidium sp. (strain 354), Monoraphidium sp. (strain 960), and Staurastrum sp.). The influence of major parameters, such as temperature, pH, in...
Logística de distribuição de água em redes urbanas: racionalização energética
Toledo,Franklina M. B.; Santos,Maristela Oliveira dos; Arenales,Marcos N.; Seleghim Júnior,PauloO problema estudado neste trabalho visa minimizar o custo de energia elétrica necessário para a operação de bombas hidráulicas, que captam água de poços artesianos para os reservatórios distribuídos em bairros da cidade, de onde a população é atendida. Como o custo da energia elétrica varia ao longo do dia, se faz necessário um planejamento da operação das bombas e armazenamento de água no sistema. Um modelo de...
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