Assessment of the Alternaria mycotoxin Tenuazonic acid in grape juice and tomato paste samples in Tabriz market

Abstract

Alternaria toxins are mycotoxins produced by Alternaria species. These fungi cause serious diseases in many crops such as cereals, oil seeds, tomato and citrus fruits, and are also common on dead organic matter. Alternaria species are widespread in both humid and semi-arid regions and can infect growing plants in the field, but also after harvest during storage and processing. More than 70 Alternaria toxins have been reported and only some of them have been physicochemically characterized. Tenuazonic acid is a toxic metabolite produced by Alternaria spp., Phoma sorghina and Pyricularia oryzae. It is considered to be one of the highest toxicity amongst the Alternaria mycotoxins Aims: The aim of this study was to determine the presence of TeA in grape juice samples and tomato paste samples. Methods: A total of 40 Grape juice and 10 Tomato paste samples were collected from Tabriz, Iran local market and were analyzed for TeA contamination via HPLC-UV. Analyte extraction was done by acetonitrile/water/formic acid (84/16/1 mL/mL/mL). Results: The Lower limit of quantitation and the upper limit of quantification for the developed method were 10 µg/L and 1000 µg/L respectively. Recovery ranged was between 96 to 108 %. The results showed 35% of grape juice samples. Tomato paste was not detectable due to peak overlap, but the grape juice was well studied. Discussion and Conclusion: This is the first study on the presence of TeA in Iranian food samples and showed that the necessity of more supervision on the production of grape juice.