Ethnobotanical clues for the discovery of natural product mediators of microbial pathogenesis

Ethnobotanical research offers unique insight into traditional pharmacopeias, which often integrate both psychological and pharmacological aspects to improving human health. The holistic nature of ethnomedicine is frequently poorly understood -and consequentially often dismissed as placebo when viewed through the lens of biomedicine. For example, anti-infective remedies that do not exhibit microbial killing or growth inhibitory activity in laboratory studies have commonly been abandoned for their “lack of efficacy”. More recently, new approaches that take into account pathogenesis in pharmaceutical R&D have also been applied to ethnopharmacological studies, resulting in the discovery of new anti-pathogenesis leads. Importantly, incorporation of this approach offers an alternative explanation as to how and why some traditional remedies can still be effective without actually killing or diminishing growth of the pathogen.

In this talk, I will discuss some of the exciting discoveries resulting from more than a decade of ethnobotanical research undertaken in the Mediterranean. In particular, I will highlight studies evaluating medicinal plants used in the treatment of skin and soft tissue infection that have led to the isolation of extracts with potent biofilm inhibitors (i.e. ellagic acid derivatives isolated from Rubus ulmifolius that inhibit biofilm formation and improve antibiotic efficacy) and quorum sensing inhibitors that target and disrupt the agr signaling pathways in multidrug-resistant isolates of Staphylococcus aureus. Lastly, I will discuss how in addition to validating the efficacy of these age-old remedies, such studies can also contribute to the greatly diminished pipeline of new antibiotics and lead to the improvement of human health.