Liquid chromatographic determination of Alternaria toxins in carrots.
A liquid chromatographic (LC) method was developed for the determination of Alternaria radicina and A. alternata toxins in carrots. Toxins were extracted from carrot with an acidified mixture of water-methanol-acetonitrile. The filtered extract was divided in 2 parts that were purified by solid-phase extraction on a C18 column for the analysis of radicinin (RAD), altertoxin-I (ATX-I), alternariol (AOH), and alternariol methyl ether (AME), and on a polymeric Oasis HLB column for tenuazonic acid (TeA). Toxins were quantified by reversed-phase LC with UV diode array detection by using 2 consecutive isocratic mixtures of acetonitrile-sodium dihydrogen phosphate solution. Mean recoveries of TeA, ATX-I, AME, RAD, and AOH from carrots spiked at levels between 0.5 and 3.0 microg/g were 69, 71, 90, 36, and 78%, with mean within-laboratory repeatability of 14, 5, 4, 6, and 18%, respectively. The mean between-laboratory reproducibilities for the determination of TeA, ATX-I, AME, and RAD in spiked samples were 25, 22, 6, and 12%, respectively. Limits of detection (signal-to-noise ratio of 3) for RAD, TeA, ATX-I, AME, and AOH were 0.006, 0.02, 0.02, 0.01, and 0.005 microg/g, respectively. RAD was detected (0.16-13.9 microg/g) in 3 out of 266 carrot samples produced under organic conditions in 3 European locations, whereas A. alternata mycotoxins were not found in any tested samples.
Solfrizzo
Michele
M
Institute of Sciences of Food Production, CNR, Viale Luigi Einaudi, 51, 70125 Bari, Italy. michele.solfrizzo@ispa.cnr.it
De Girolamo
Annalisa
A
Vitti
Carolina
C
Visconti
Angelo
A
van den Bulk
Ruud
R
D000528:Alternaria / Q000737:chemistry*; D002138:Calibration; D002853:Chromatography, Liquid; D018552:Daucus carota / Q000737:chemistry*; D007202:Indicators and Reagents; D009183:Mycotoxins / Q000032:analysis*; D012996:Solutions; D012997:Solvents; D013056:Spectrophotometry, Ultraviolet
D007202:Indicators and Reagents; D009183:Mycotoxins; D012996:Solutions; D012997:Solvents