Compounds from natural sources for new diagnostics and drugs against biofilm infections

Biofilm infections represent a new medical challenge that drives towards the discovery of new diagnostics and new drugs specifically designed for this purpose. All living organisms offer a huge source of compounds which represent the biochemical substrate of the biological competition on the Earth and can be used to this aim. We describe an innovative diagnostic tool to early diagnose medical device infections sustained by Staphylococci; then we list new compounds that modulate bacterial phenotype and reduce virulence without affecting bacterial viability so as to avoid the emergence of genetic resistances. These compounds are all derived from natural sources: prokaryotes, plants, and human body. From prokaryotes we studied new compounds extracted from different environmental bacterial species, including Antarctic species growing in extreme environments. We describe also the anti-biofilm properties of extracts obtained from plants well known since centuries in folk medicine. The humoral immune response is the source of the last anti-biofilm compound: transferrin (Tf), a protein derived from human plasma involved in inflammation and natural immunity. All these compounds can be used as scaffolds for the design of new drugs active on the sessile form of pathogens prevalent in human biofilm infections.