The broccoli-derived antioxidant sulforaphane changes the growth of gastrointestinal microbiota, allowing for the production of anti-inflammatory metabolites

Sulforaphane is a naturally occurring, potent antioxidant, found in Brassicaceae plants such as broccoli, and is being considered for use in the treatment of fibrosis, cancer and preeclampsia. As sulforaphane is orally administered and has been shown to demonstrate antimicrobial properties in aerobic conditions, there is also the potential for impact on the gut microbiome under anaerobic conditions. Here, we have determined the effect of sulforaphane on the growth of 43 common human gastrointestinal microbiota, representing common commensals and pathogens. The enteropathogenic Escherichia coli strain EPEC E2348/69 showed the most significant increases in growth in the presence of sulforaphane. Proteomic analysis of this isolate showed that sulforaphane increased anaerobic respiration, whilst metabolomics identified differentially produced metabolites that can decrease inflammation in human cells. Therefore, sulforaphane can increase growth of specific gastrointestinal microbiota, correlating with increased production of anti-inflammatory metabolites. Thus, providing a novel mechanism for modulating inflammatory states in patients.