Hickert, Sebastian Krug, Isabel Cramer, Benedikt Humpf, Hans-Ulrich Detection and Quantitative Analysis of the Non-cytotoxic <i>allo</i>-Tenuazonic Acid in Tomato Products by Stable Isotope Dilution HPLC-MS/MS Tenuazonic acid (<b>1</b>) is a mycotoxin produced mainly by fungi of the genus <i>Alternaria</i>. It occurs in a variety of agricultural products. <i>allo</i>-Tenuazonic acid (<b>2</b>) is an isomer of <b>1</b> that is not chromatographically separated from <b>1</b> in most analytical methods. Therefore, both isomers are quantitated as a sum parameter. In this study a QuEChERS (quick, easy, cheap, effective, rugged and safe) based stable isotope dilution HPLC-MS/MS method including the chromatographic separation of both isomers was developed and applied to 20 tomato products from the German market. All products showed contamination with both toxins. <b>1</b> was found in a range from 5.3 ± 0.1 to 550 ± 15 μg/kg (average = 120 μg/kg) and <b>2</b> in a range from 1.5 ± 0.4– to 270 ± 0.8 μg/kg (average = 58 μg/kg). <b>2</b> represents 7.0–44% of the sum of both isomers (average = 29%). This is the first reported occurrence of <b>2</b> in food samples. To evaluate and compare the cytotoxicities of <b>1</b> and <b>2</b>, both compounds were isolated from a synthetic racemic mixture. <b>1</b> showed moderate cytotoxic effects on HT-29 cells starting at 100 μM, whereas <b>2</b> exhibited no activity. <b>2</b> was not produced in liquid cultures of Alternaria alternata in yeast extract sucrose (YES) medium, but could be detected in small amounts in tomato puree inoculated with the fungus. food samples;genus Alternaria;sum parameter;Quantitative Analysis;HT;acid;method;Alternaria alternata;YES;100 μ M;racemic mixture;20 tomato products;German market;tomato puree inoculated;isomers;cytotoxic effects;Tomato Products 2015-12-23
    https://acs.figshare.com/articles/journal_contribution/Detection_and_Quantitative_Analysis_of_the_Non_cytotoxic_i_allo_i_Tenuazonic_Acid_in_Tomato_Products_by_Stable_Isotope_Dilution_HPLC_MS_MS/2095612
10.1021/acs.jafc.5b04812.s001