ISAPP moves to define definition and scope of postbiotics The International Scientific Association for Probiotics and Prebiotics (ISAPP) has clarified the term ‘postbiotics’ in a statement that responds to the scientific groundswell and growing number of postbiotic applications. Writing in Nature Reviews, postbiotics is now defined as, ‘a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host.’ Examples of a postbiotic can therefore be whole microbial cells or components of the cells, that have been deliberately inactivated. “With this definition of postbiotics, we wanted to acknowledge that different live microorganisms respond to different methods of inactivation," says Professor Seppo Salminen, lead author of the publication.