Sofie Monbaliu

In recent years the consumption of tea and herbal infusions has increased. These hot drinks are consumed as daily drinks as well as for medicinal purposes. All tea varieties (white, yellow, green, oolong, black and puerh) originate from the leaves of the tea plant, Camellia sinensis. All extracts made of plant or herbal materials which do not contain Camellia sinensis are referred as herbal infusions or tisanes. During processing and manufacturing fungal contamination of the plant materials is possible, enabling contamination of these products with mycotoxins. In this study a multimycotoxin UPLC−MS/MS method was developed and validated for the analysis of the raw tea and herbal infusion materials as well as for their drinkable products. The samples were analyzed by ultra-high-performance liquid chromatography−tandem mass spectrometry (UPLC−MS/MS), with a mobile phase consisting of variable mixtures of water and methanol with 0.3% formic acid. The limits of detection for the different mycotoxins varied between 2.1 μg/kg and 121 μg/kg for raw materials and between 0.4 μg/L and 46 μg/L for drinkable products. Afterward 91 different tea and herbal infusion samples were analyzed. Only in one sample, Ceylon melange, 76 μg/kg fumonisin B₁ was detected. No mycotoxins were detected in the drinkable products.

In this work the presence and migration behavior of mycotoxins formed in sweet pepper, inoculated by Fusarium species involved in internal fruit rot, were investigated. Two different commercial sweet pepper cultivars were inoculated with two different Fusarium proliferatum isolates that were sampled from diseased peppers. After 10 days of incubation at 20 °C in a closed container, the lesion caused by the fungal infection was dissected. Around the lesion, up to three concentric rings of pepper fruit tissue with a width of 5 mm were cut out and analyzed using a multimycotoxin LC-MS/MS method. The analyses resulted in the detection of beauvericin and fumonisins B₁, B₂, and B₃. Beauvericin was detected only in the lesions (95%), and the levels varied between 67 and 73800 μg/kg. Fumonisins B₁, B₂, and B₃ were detected in the lesions and in the surrounding tissue, indicating migration of these toxins into healthy parts of the sweet pepper. In the lesion the fumonisin B₁ level varied between 690 and 104000 μg/kg. Even in the outer ring fumonisin B₁ was still present. Mostly it was present at a lower level than in the lesion, with a maximum level of 556 μg/kg. A similar migration behavior was obtained for fumonisins B₂ and B₃, but lower levels were detected in the lesions, up to 10900 and 1287 μg/kg, respectively. The analysis of 20 pepper samples resulted in the detection of beauvericin or alternariol. Seven samples were contaminated, and the level of beauvericin was 124 μg/kg (N = 1), whereas the level of alternariol varied from below the LOQ (6.6 μg/kg) to 101 μg/kg (N = 6).

Crops used for animal feed can be easily contaminated by fungi during growth, harvest, or storage, resulting in the occurrence of mycotoxins. Because animal feed plays an important role in the food safety chain, the European Commission has set maximum levels for aflatoxin B₁ and recommended maximum levels for deoxynivalenol, zearalenone, ochratoxin A, and the sum of fumonisin B₁ and B₂. A multimycotoxin LC-MS/MS method was developed, validated according to Commission Decision 2002/657/EC and EN ISO 17025 accredited for the simultaneous detection of 23 mycotoxins (aflatoxin-B₁, aflatoxin-B₂, aflatoxin-G₁, aflatoxin-G₂, ochratoxin A, deoxynivalenol, zearalenone, fumonisin B₁, fumonisin B₂, fumonisin B₃, T2-toxin, HT2-toxin, nivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, diacetoxyscirpenol, fusarenon-X, neosolaniol, altenuene, alternariol, alternariol methyl ether, roquefortine-C, and sterigmatocystin) in feed. The decision limits of the multimycotoxin method varied from 0.7 to 60.6 μg/kg. The apparent recovery and the results of the precision study fulfilled the performance criteria as set in Commission Decision 2002/657/EC. The analysis of three different feed matrices (sow feed, wheat, and maize) provided a good basis for the evaluation of the toxin exposure in animal production. In total, 67 samples out of 82 (82%) were contaminated; type B-trichothecenes and fumonisins occurred most often. The majority of the infected feed samples (75%) were contaminated with more than one type of mycotoxin.

A multi‐mycotoxin method was developed for the simultaneous determination of trichothecenes (nivalenol, deoxynivalenol, 3‐acetyldeoxynivalenol, 15‐acetyldeoxynivalenol, neosolaniol, fusarenon‐X, diacetoxyscirpenol, HT‐2 toxin, T‐2 toxin), aflatoxins (aflatoxin‐B ₁ , aflatoxin‐B ₂ , aflatoxin‐G ₁ and aflatoxin‐G ₂ ), Alternaria toxins (alternariol, alternariol methyl ether and altenuene), fumonisins (fumonisin‐B ₁ , fumonisin‐B ₂ and fumonisin‐B ₃ ), ochratoxin A, zearalenone, beauvericin and sterigmatocystin in sweet pepper. Sweet pepper was extracted with ethyl acetate/formic acid (99:1, v/v). After splitting up the extract, two‐thirds of the extract was cleaned up using an aminopropyl column followed by an octadecyl column. The remaining part was cleaned up using a strong anion‐exchange column. After recombination of both cleaned parts of the sample extract, the combined solvents were evaporated and the residue was dissolved in mobile phase; 20 µL was injected into the chromatographic system, so only one run was used to separate and detect the mycotoxins in positive electrospray ionization using selected reaction monitoring. The samples were analyzed with a Micromass Quattro Micro triple quadrupole mass spectrometer (Waters, Milford, MA, USA). The mobile phase consisted of variable mixtures of water and methanol, 1% acetic acid and 5 mM ammonium acetate. The limits of detection of the multi‐mycotoxin method varied from 0.32 µg.kg ⁻¹ to 42.48 µg.kg ⁻¹ . The multi‐mycotoxin liquid chromatography/tandem mass spectrometry (LC/MS/MS) method fulfilled the method performance criteria required by the Commission Regulation (EC) No 401/2006. Sweet peppers inoculated by Fusarium species were analyzed using the developed method. Beauvericin (9–484 µg.kg ⁻¹ ) and fumonisins (fumonisin‐B ₁ up to 4330 µg.kg ⁻¹ , fumonisin‐B ₂ up to 4900 µg.kg ⁻¹ , and fumonisin‐B ₃ up to 299 µg.kg ⁻¹ ) were detected. Copyright © 2008 John Wiley & Sons, Ltd.