A Specific Probiotic in thE MOdulation of Gut Microbiota of patieNts With Mild-to-modErate Ulcerative Colitis (ANEMONE)

The concept of probiotics dates back to 1907, when Elie Metchnikoff observed that elderly Bulgarian populations consuming fermented dairy products, such as yogurt rich in lactic acid bacteria (LAB), appeared to have increased longevity. This observation formed the basis for the development of traditional probiotics.

Traditional probiotics are defined as live microorganisms that confer a health benefit when administered in adequate amounts. These microbes are typically derived from fermented foods or the human gastrointestinal tract. Most belong to a limited number of well-characterized genera, particularly Lactobacillus and Bifidobacterium. Certain strains of these bacteria are recognized as safe and have been granted Qualified Presumption of Safety (QPS) status by the European Food Safety Authority (EFSA). In addition, they are technologically robust, meaning they can be easily cultivated and mass-produced for industrial applications.

Despite their popularity and widespread use in dietary supplements and functional foods, traditional probiotics are not specifically developed as treatments for diseases. Their mechanisms of action include modulation of gut microbiota, enhancement of the gut barrier, and interaction with the immune system. However, most supporting evidence comes from laboratory (in vitro), animal, or ex vivo studies rather than strong clinical trials. As a result, EFSA has evaluated more than 400 probiotic-related claims but has not approved any specific health claims due to insufficient conclusive evidence.

In recent years, advances in microbiota and microbiome research-particularly through metagenomics and microbial profiling-have significantly expanded our understanding of the gut ecosystem. It is now well established that dysbiosis, or imbalance in gut microbiota composition, is associated with a wide range of diseases, including metabolic, immune, and inflammatory disorders.

These scientific developments have led to the identification of new microorganisms that are associated with healthy individuals rather than traditional dietary sources. These microbes are classified as Next-Generation Probiotics (NGPs) or Live Biotherapeutic Products (LBPs). Unlike traditional probiotics, NGPs are not restricted to classical genera and do not have a long history of safe human use. Instead, they are often identified through comparative studies analyzing differences between healthy and diseased microbiomes.

NGPs represent a promising new frontier in microbiota-based therapies, as they may be specifically selected or engineered to target particular diseases or health conditions. A growing number of potentially beneficial species have been identified, opening new opportunities for precision medicine and personalized interventions based on gut microbiota composition.