A new research project has shown that the study bacteria in the human digestive tract can break down the complex carbohydrates that make up the yeast cell wall. The types of yeasts targeted are those used to make bread and beer, two “staples” of human diets around the world (in addition to these, soy sauce and other fermented products can be added.)
The main type of bacterium involved in this yeast-munching process is Bacteroides thetaiotomicron and this organism can break down yeasts found exclusively in the human gut. Scientists argue that a more extensive use of this bacterium, perhaps as a probiotic (a live bacterial culture), could treat a range of diseases associated with the human gut. This includes bowel problems and autoimmune diseases.
The types of complex carbohydrates processed are called yeast mannans. The breakdown of yeasts is part of the process where the collective microbes in the gut (microbiome) obtain nutrients from the food ingested by people. Some parts of this process are seen as beneficial and there has been considerable research about how the gut microbiome influences human health. Some bacteria, through processing certain foods, are able to produce molecules that have beneficial health effects.
The researchers hope that the new understanding about the type of bacterium and the way that it processes yeast carbohydrate will lead to better knowledge about nutrition and health.
The research so far has received positive comments from the U.S. Food and Drug Adminsitration (FA). The bacterium — Bacteroides thetaiotomicron — has been granted Orphan Designation by the FDA for Paediatric Crohn’s Disease (under a patent called Thetanix). This is because yeast mannan may have health promoting effects on the microbiome and could alleviate some of the effects associated with Crohn’s Disease.
Crohn’s disease is a type of inflammatory bowel disease that may affect any part of the gastrointestinal tract from mouth to anus. Symptoms often include: abdominal pain, diarrhea (which may be bloody if inflammation is severe), fever and weight loss
The research has been carried out at Newcastle University in the U.K. in collaboration with researchers based at the University of Michigan. The findings have been published in the science journal Nature. The study is called “Human gut Bacteroidetes can utilize yeast mannan through a selfish mechanism.”
