Influence of Cooking (Microwaving and Broiling) on Cylindrospermopsin Concentration in Muscle of Nile Tilapia (Oreochromis niloticus) and Characterization of Decomposition Products

Abstract

Cylindrospermopsin (CYN) has become increasingly important as a freshwater algal toxin, showing cytotoxic effects. This toxin is able to bioaccumulate in freshwater food webs, representing a serious human health problem. Normally, fish is cooked before consumption, and CYN concentration can be altered. For the first time, the effects of microwaving and broiling for 1 and 2 min on CYN concentration and its decomposition products in fish muscle (Oreochromis niloticus) contaminated in the laboratory were investigated, using UPLC-MS/MS and Orbitrap. The results show that cooking the fish reduced unconjugated CYN levels by 11, 10 and 15% after microwaving for 1 and 2 min, and broiling for 2 min, respectively, compared to control fish. Different CYN decomposition products with m/z 416.1234 (7-epi-CYN) and m/z 336.16663 (diasteroisomers C-3A, C-3C, C-3D, C-3E, C-3F) are generated in fish samples submitted to cooking. Based on the relative abundance of the decomposition products, the possible degradation pathways taking place by microwaving may be through the formation of 7-epi-CYN and m/z 336.16663 compounds, whereas in the case of broiling the last route is the only one observed in this study. The influence of cooking and the toxicity characterization of the degradation products generated in CYN-contaminated fish are of importance for more realistic risk evaluation related to their consumption.

Validation of a Method for Cylindrospermopsin Determination in Vegetables: Application to Real Samples Such as Lettuce (Lactuca sativa L.)

“…Before testing the efficiency of the CYN extraction method, the UPLC–MS/MS method was setup for this purpose. For this, commercially purchased CYN standard solutions were tested, acquiring mass spectra and adjusting the mobile phase strength, as previously performed in our laboratory [ 55 , 56 ]. The spectrum was obtained on collision of m / z 416, corresponding to the pseudomolecular ion [M + H] + .…”

“…In fact, and specifically in relation to the matrices assayed in the present study, CYN has been detected in Brassica vegetables, lettuce, and arugula by ELISA and LC–MS/MS [ 37 , 42 ], but these methods have not been validated. Ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) allows excellent specificity and sensitivity for cyanotoxins detection and quantification in waters and also in more complicated matrices, becoming the technique of choice for these purposes [ 54 , 55 , 56 ].…”

Detection of cylindrospermopsin and its decomposition products in raw and cooked fish (Oreochromis niloticus) by analytical pyrolysis (Py-GC/MS)

“…Moreover, one raw muscle sample without toxin was selected as negative control (C-). CYN concentration was selected taking into account naturally environmental data in aquatic organisms reported by other studies (Freitas et al, 2016;Gutiérrez-Praena et al, 2013;Prieto et al, 2017).…”

“…Recently, our research group has shown changes in the concentration of CYN and the formation of their DP in contaminated fish muscle subjected to different cooking techniques such as microwaving, broiling, boiling or steaming by UPLC-MS/MS Prieto et al, 2017). Taking this into account, the aim of the present work was to investigate the suitability of Py-GC/MS as a simple, fast and economical analytical technique for CYN and its DP detections in raw and cooked fish samples before consumption.…”

New Method for Simultaneous Determination of Microcystins and Cylindrospermopsin in Vegetable Matrices by SPE-UPLC-MS/MS

“…Mass spectrometry (MS) techniques are a powerful tool for the analysis of biotoxins [ 27 ], and it has been employed in the case of MCs detection in natural blooms, cyanobacterial strains, fish, and other biological samples [ 28 , 29 , 30 ]. Specifically, ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) allows excellent specificity and sensitivity for cyanotoxins’ detection and quantification in waters and in more complicated matrices, becoming the preferred technique for cyanotoxin analysis [ 16 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ]. Previous studies were carried out in our laboratory for the determination of CYN in water [ 38 ], fish [ 39 ], and vegetables [ 40 ].…”