Validated UPLC-MS/MS Methods To Quantitate Free and Conjugated Alternaria Toxins in Commercially Available Tomato Products and Fruit and Vegetable Juices in Belgium

Abstract

Ultra-performance liquid chromatography tandem mass spectrometry and Quick, Easy, Cheap, Effective, Rugged and Safe based analytical methodologies to quantitate both free (alternariol (1), alternariol monomethyl ether (2), tenuazonic acid (3), tentoxin (4), altenuene (5), altertoxin-I (6)) and conjugated (sulfates and glucosides of 1 and 2) Alternaria toxins in fruit and vegetable juices and tomato products were developed and validated. Acceptable limits of quantitation (0.7-5.7 µg/kg), repeatability (RSD r < 15.7%), reproducibility (RSD R < 17.9%) and apparent recovery (87.0-110.6%) were obtained for all analytes in all matrices investigated. 129 commercial foodstuffs were analyzed, and 3 was detected in 100% of tomato product samples (<LOQ to 333 µg/kg), while 1, 2, 4 and 5 were also frequently detected (21-86%, <LOQ to 62 µg/kg). Moreover, low levels (<LOQ to 9.9 µg/kg) of modified Alternaria toxins (sulfates of 1 and 2) were repeatedly detected. A deterministic dietary exposure assessment revealed the possible risk for human health related to the presence of 1 and 2 in tomato based foodstuffs, whereas 3 is unlikely to be of human health concern.

AlternariaMycotoxins in Food and Feed: An Overview

“…defining a mycotoxin derivative that may be cleaved during digestion in living organisms to release its parent form. However, these conjugated mycotoxins are currently known as "modified mycotoxins" after a more recent comprehensive classification [47]. It is not clear if these modified mycotoxins can be hydrolyzed and absorbed in the gastrointestinal tract, thereby further contributing to the overall exposure.…”

“…Alternaria toxins are, together with aflatoxins, ochratoxin A, and patulin, the most commonly found mycotoxins in fruits and their processed products. Due to the limitations of current industrial processes to completely eliminate the rotten tissues and the reported stability of some Alternaria mycotoxins (i.e., AOH, AME, and ATXs) in fruit juices and during tomato processing, it is obvious that these mycotoxins are likely to be present in commercial end products [47].…”

“…Consequently, Alternaria mycotoxins were detected in cereals and derived products [46,[57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76], feed [74,[109][110][111][112][113], dairy products [114], grapes and by-products [27,77,115], tomatoes and derived products [31,47,77,81,106,113], nuts and by-products [102,116], spices [117], soybeans [76,116,118], sunflower seeds [85,104,107], vegetables [27,101], vegetable oils [105], strawberries …”

“…These were followed by Alternaria toxins ATXs included in 16% of the analyzed studies, whereas only a few publications reported other compounds such as macrosporin (9%), monocerin, ALN, AALs, and infectopyrone (all <3%). Notably, limited information was found about pyrenochaetic acid A (PyA), alternarienonic acid (AIA), and alloTeA and isoALT, recently reported in food samples for the first time [31,105] and metabolites such as AOH3S, AOH3G, AME3S, and AME3G [47,69]. In this way, AOH, AME, TeA, and TEN have been shown to occur in food samples frequently [82,97,108], while the occurrence of ALT, isoALT, ATX-I, and AAL toxins is of much lower incidence, mainly due to shortcomings in current analytical methodologies.…”

Development of an Immunochromatographic Strip Test for the Rapid Detection of Alternariol Monomethyl Ether in Fruit

“…The derivatization results in potential disadvantages for GC analysis such as matrix interference, the time-consuming nature of the process, the need for an expensive derivatization reagent, and so on. In the last few years, LC-MS, especially LC tandem mass spectrometry (LC-MS/MS), has played an important role in AME detection without derivatization [10,11,12]. However, these methods need highly qualified technicians and can only be carried out in the lab.…”