An overwhelming interest in the gut microbiome has led to many studies showing possible links to positive and negative health states. A healthy gut microbiome has the potential to improve immunity, cognitive function, mineral absorption and general metabolism. Alternatively, an unhealthy gut microbiome could be a contributing factor for chronic inflammation, obesity, allergies, autism, asthma and cancer. This increased awareness of the gut microbiome has stimulated an increased interest in prebiotic fibers and the role they can play in developing a healthy gut microbiome.

Dietary fibers derived from complex carbohydrates form an important class of products in the functional food industry. Non digestible carbohydrates resist digestion and absorption in the human small intestine with complete or partial fermentation in the large intestine and some act as prebiotics. Most chronic colonic diseases originate in the distal colon, often associated with production of toxic metabolites. Consequently, there is a great interest in finding different prebiotics that exert positive fermentation activity throughout the entire colon, especially the distal colon.

Several dynamic in vitro simulators have been created in the last few years to reproduce parts or the entire gastro intestinal tract and the physiological parameters that influence the gastro intestinal microbial community and its metabolic activity. Among the available systems, the Simulator of Human Intestinal Microbial Ecosystem (SHIME®, ProDigest, Belgium) is a useful model for nutritional research in terms of analysis of intestinal microbial community composition and activity. The SHIME® model consists of a succession of 5 reactors simulating stomach, small intestine, and the 3 areas of the colon (ascending, transverse, and descending). Recent advances now allow researchers to combine continuous model with the study of bacteria–host interactions—such as mucosal adhesion (M-SHIME®) and interaction with the immune system (co-cultures of enterocytes and immune cells).

The effect of soluble corn fiber (SCF; Promitor®SCF 85, Tate & Lyle) has been investigated in the SHIME®. The use of the SHIME® showed PROMITOR® Soluble Corn Fiber is a unique prebiotic fiber that supports the growth of healthy gut microbiota through all three sections of the colon and leads to positive effects on the gut microbiota’s activity and composition (e.g. increase in mucosal Lactobacillus, bifidogenic effect at luminal and mucosal levels). These effects seem to result in immunomodulatory properties and strengthening of the gut barrier as shown through expression of anti-inflammatory properties in the distal colon and increased transepithelial electrical resistance.