Stability of Mycotoxins in Individual Stock and Multi-Analyte Standard Solutions

Abstract

Standard solutions of mycotoxins prepared in RP HPLC solvents from neat standards are usually used for analytical method development. Multi-mycotoxin HPLC-MS/MS methods necessitate stability estimation for the wide spectrum of fungal metabolites. The stability of individual diluted stock standard solutions of mycotoxins in RP-HPLC solvents and multi-analyte HPLC-MS/MS calibrants was evaluated under standard storage and analysis conditions. Individual stock standard solutions of aflatoxins, sterigmatocystin, A-and B-trichothecenes, zearalenone and its analogues, ochratoxin A, fumonisins, Alternaria toxins, enniatins and beauvericin, moniliformin, citrinin, mycophenolic, cyclopiazonic acids and citreoviridin were prepared in RP-HPLC solvents and stored at −18 • C for 14 months. UV-spectroscopy was utilized to monitor the stability of analytes, excluding fumonisins. The gradual degradation of α-, β-zearalenol and α-, β-zearalanol in acetonitrile was detected. Aflatoxins and sterigmatocystin, zearalenone, Alternaria toxins, enniatins and beauvericin, citrinin, mycophenolic, cyclopiazonic acids and citreoviridin can be referred to as stable. The concentration of the majority of trichothecenes should be monitored. Diluted multi-mycotoxin standard in water/methanol (50/50 v/v) solutions acidified with 0.1% formic acid proved to be stable in silanized glass at 23 • C exposed to light for at least 75 h (CV ≤ 10%). An unexpected manifestation of MS/MS signal suppression/enhancement was discovered in the course of multi-mycotoxin standard solution stability evaluation. Key Contribution:The stability of the wide spectrum of mycotoxins in individual standard solutions in RP-HPLC solvents and multi-analyte HPLC-MS/MS calibrants under standard storage and analysis conditions is discussed basing on experimental and literature data.

Determination of Alternaria Toxins in Tomato, Wheat, and Sunflower Seeds by SPE and LC-MS/MS—A Method Validation Through a Collaborative Trial

“…The slopes of the linear regressions did not deviate significantly from zero in any of the cases, at 95% confidence level, hence the materials were declared stable at 4 °C and −18 °C. Previous works corroborate the stability of the ATs in solvent and tomato juice during several months ( 20 , 21 ). To ensure that the temperature of the test materials would not exceed 4 °C during transport, the samples were dispatched in polystyrene boxes filled with dry ice.…”

Exploration on the Enhancement of Detoxification Ability of Zearalenone and Its Degradation Products of Aspergillus niger FS10 under Directional Stress of Zearalenone

“…The enzyme also cannot tolerate high temperatures. Previous studies have shown that microorganisms can secrete extracellular enzymes for mycotoxin degradation or dealing with other adverse conditions [36].…”

DFT Modelling of Molecular Structure, Vibrational and UV-Vis Absorption Spectra of T-2 Toxin and 3-Deacetylcalonectrin

“…The choice of methanol as a solvent is explained by the studied sample solubility and the transparency in the considered spectral range, as well as a standardized technique for the absorption spectra registration. Furthermore, liquid chromatography experiments with methanol were tested in several different independent laboratories [33], which allows comparison of the obtained theoretical results with the experimental data presented in [1,33,34]. The singlet approach simulation of the 60 lowest excited states, as well as calculation of the oscillator strength for transitions…”

“…The T-2 toxin and 3-deacetylcalonectrin are A-type trichothecene micotoxines [1][2][3]. These toxins are produced by various Fusarium fungi [1,2].…”

“…The T-2 toxin and 3-deacetylcalonectrin are A-type trichothecene micotoxines [1][2][3]. These toxins are produced by various Fusarium fungi [1,2]. In particular, 3-deacetylcalonectrin has been extracted from F. graminearum and F. culmorum [4], while the T-2 toxin has been excreted by F. sporotrichioides, F. tricinctum and F. poae [5].…”