Masked fungal toxins in our food

Abstract

When fungi attack agricultural crops, they don’t just decrease yield, they can also leave behind poisonous compounds on the harvest. Although food safety scientists have long monitored these fungal products, known as mycotoxins, in recent years they’ve discovered that plants can chemically modify the compounds for their own survival, say, by adding a protective sugar group. However, food safety tests don’t currently look for these masked mycotoxins. Furthermore, the masked mycotoxins “may be hydrolyzed in the [human] digestive tract, thereby releasing the parental form and increasing the total exposure to the toxin,” notes a research team led by Sabine E. Kulling of the German Federal Research Institute of Nutrition & Food (J. Agric. Food Chem. 2016, DOI: 10.1021/acs.jafc.6b03120). Kulling and her colleagues report that when Alternaria alternata infects tomato cells, the fungus first decorates its toxins—including alternariol (shown)—with a sulfate group and then the tomato’s enzymes add a glucoside. Because