Figure 11. Microbial β-glucuronidase potential substrate pool of compounds structurally similar to SN-38G.

(a) SN-38G conversion to SN-38 in the gut is mediated by microbial β-glucuronidases. (b) The substrate pool for β-glucuronidases with above threshold substructure overlap with SN-38G are members of a diverse range of chemical structure superclasses as defined by FooDB chemical ontology (Wishart, 2018). (c) These compounds include glucuronidated food-derived compounds (purple), endogenous glucuronides (tan) and other non-glucuronides (blue).