A rapid and inexpensive method to screen for common foods that reduce the action of acrylamide, a harmful substance in food.

By DNA microarray and protein 2-DE screens for Caenorhabditis elegans genes up-regulated by acrylamide, we selected the gst-4 gene and constructed a gst::gfp fusion gene, which was used to transform C. elegans into a biosensor for acrylamide. This biosensor detects acrylamide as a GFP-expression signal in a dose- and time-dependent manner. When the biosensor was exposed to acrylamide together with commercially available powdered green tea, GFP levels decreased to the control level, suggestive of acrylamide detoxification or prevention of GST induction. The present methodology should be applicable for screening of not only harmful substances but also substances that reduce or counteract their harmfulness or action, with appropriately constructed visible biosensors.