AHR and hepatocellular carcinoma: However, in our AhR assay, supernatants of reutericyclin producer strains L. reuteri TMW1.112 and TMW1.656 were toxic to hepatoma cells; thus, we were not able to assess the potential of these PKS-encoding sourdough isolates to activate AhR, and it was outside the scope of this work to test if the toxicity was driven by reutericyclin.