Probiotics: 100 years (1907-2007) after Elie Metchnikoff’s Observation

The scientific rationale for the use of live microbes in the prevention and treatment of infections came to lime-light most transparently at the beginning of the 20 century when Elie Metchnikoff in 1907 hypothesized that replacing or diminishing the number of ‘‘putrefactive’’ bacteria in the gut with lactic acid bacteria could normalize bowel health and prolong life. After more than half a century the term probiotics was coined to reflect Metchnikoff’’s idea. It is now defined as ‘‘live microorganism, which when administered in adequate amounts confer a health benefit on the host’’. In the last 10 years, scientific research in probiotic microbiology has progressed considerably and significant advances have been made in the selection and characterization of specific probiotic cultures and substantiation of health claims relating to their use. Molecular and genetic studies have helped to uncover the mechanistic basis for the beneficial activities of probiotics. It has taken one hundred years, but there are signs that Metchnikoff’’s hypothesis is now truly being brought to life and many health attributes will indeed be conferred by use of probiotics.