Mass spectrometry, pyrrolizidine alkaloids

Comfrey Echium gas chromatography honey feed immunoassay liquid chromatography mass spectrometry pyrrolizidine alkaloids ragwort Senecio solid phase extraction... [Pg.1050]

Gas chromatography coupled to mass spectrometry is a widely used analytical method [31] but does require prior reduction of the involatile N-oxides. Additionally, there are problems associated with some alkaloids that require prederivatization to enhance the GC characteristics. These requirements for prederivatization can adversely affect the GG-MS interpretation, especially at trace levels of alkaloids [32]. Gombined SPE-LC-MS approaches have provided methods for qualitative profiling and quantitative analysis of pyrrolizidine alkaloids and their N-oxides. [Pg.383]

There remain a large number of alkaloids, usually only trace constituents in alkaloid fractions from anuran skin extracts, that have been characterized only by gas chromatography-mass spectrometry (see Appendix for methodology). Most of these are from dendrobatid frogs, and many will undoubtedly prove to be members of izidine (pyrrolizidine, indolizid-... [Pg.269]

Pedersen has examined the pyrrolizidine alkaloid content of 19 Danish species of the Boraginaceae. The isolated alkaloids from ten of these species were purified by preparative thin-layer chromatography and investigated by mass spectrometry. The... [Pg.56]

The use of mass spectrometry has proved to be extremely helpful in pyrrolizidine alkaloid work for determining the type of base present, and the nature of the esterifying acid(s) when present. The first detailed study was reported by Neuner-Jehle et al. Laburnine (116) gives a base peak at mje 83 (134) by the usual fragmentation to the nitrogen. The same base peak has been observed for the isomeric 1-hydroxymethylpyrrolizidines by Abdullaev et aZ. °° Platynecine (43) undergoes similar fission to give ions at... [Pg.282]

AHPA. July 2011. Code of Ethics Business Conduct. Silver Spring, MD American Herbal Products Association. Altamirano, J., S.R. Gratz, and K.A. Wolnik. 2005. Investigation of pyrrolizidine alkaloids and their N-oxides in commercial comfrey-containing products and botanical materials by liquid chromatography electrospray ionization mass spectrometry. /. AOAC Int. 88(2) 406-412. [Pg.837]

Wuhloud, J.C.A., S.R. Gratz, B.M. Gamble, and K.A. Wobuk. 2004. Simultaneous analysis of hepatotoxic pyrrolizidine alkaloids and N-oxides in cornfrey root by LC-ion trap mass spectrometry. Analyst 129(2) 150-156. [Pg.841]

Bolechova, Caslavsky, Pospichalova, and Kosubova report a protocol for the extraction of selected pyrrolizidine alkaloids (PAs) in feed. They determined PAs using an ultraperformance liquid chromatography (UPLC) system coupled to a tandem mass spectrometry equipped with an electrospray interface (ESI). Their steps to extract alkaloids for this determination are as follows ... [Pg.443]

Kempf M, Beuerle T, Biihringer M, Denner M, Trost D, von der Ohe K, Bhavanam VBR, Schreier P (2008) Pyrrolizidine alkaloids in honey risk analysis hy gas chromatography—mass spectrometry. Mol Nutr Food Res 52 1193-1200... [Pg.1066]

Zhou Y, Li N, Choi FF-K, Qiao C-F, Song J-Z, Li S-L, Liu X, Cai Z-W, Fu PP, Lin G, Xu H-X (2010) A new approach for simultaneous screening and quantification of toxic pyrrolizidine alkaloids in some potential pyrrolizidine alkaloid-containing plants by using ultra performance liquid chromatography-tandem quadrupole mass spectrometry. Anal Chim Acta 681 33 0... [Pg.1066]

Witte L, Rubiolo P, Bicchi C, Hartmann T (1993) Comparative analysis of pyrrolizidine alkaloids from natural sources by gas chromatography-mass spectrometry. Phytochemistry 32 187-196... [Pg.1066]

Bredenkamp MW (1991) The mass spectrometry of pyrrolizidine alkaloids. In Rizk AM (ed) Naturally occurring pyrrolizidine alkaloids. CRC Press, Boca Raton... [Pg.1066]

Bicchi C, Caniato R, Tabacchi R, Tsoupras G (1989) Capillary gas-chrmnatography positive and negative-ion chemical ionization mass-spectrometry on pyrrolizidine alkaloids of Senecio inaequidens using ammonia and hydroxyl ions as the reagent speeies. J Nat Prod 52 32-41... [Pg.1066]

Huizing HJ, Deboer F, Hendriks H, Balraadjsing W, Bruins AP (1986) Positive and negative-ion chemical ionization mass spectrometry of trimethylsilyl derivatives of pyrrolizidine alkaloids using (NH)H and (OH)H as the reactant ions. Biotned Envitmt Mass Spectnnn 13 293-298... [Pg.1066]

Liu F, Wan SY, Jiang Z, Li SFY, Qng ES, Osorio JCC. Determination of pyrrolizidine alkaloids in comfrey by liquid chromatography—electrospray ionization mass spectrometry. Talanta 2009 80 916-23. [Pg.537]

Gas liquid chromatography — mass spectrometry of silylated derivatives is a very sensitive method for detection of pyrrolizidine alkaloids 111). The many alkaloids containing retronecine (18) can be readily determined either by H n.m.r. spectroscopy utilising the downfield signal for the vinyl proton 211) or by gas liquid chromatography of fluorinated retronecine derivatives 101). [Pg.133]

Pedersen, E., and E. Larsen Mass Spectrometry of Some Pyrrolizidine Alkaloids. Org. Mass Spectrom. 4, 249 (1970). [Pg.197]

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