When experimenting with sterile mice, these mice were under sterile conditions since birth and had never encountered microorganisms in their lives. The researchers noticed that none of the feces samples of these sterile animals would float but would sink immediately. This prompte

When experimenting with sterile mice, these mice were under sterile conditions since birth and had never encountered microorganism in their lives. The researchers noticed that none of the feces samples of these sterile animals would float, but would sink immediately. This prompted them to think of an interesting idea.

American Mayo Clinic is one of the largest private medical and research centers in the world, and the experiment Pathology , gastroenterology and laboratory medicine employees have managed to find the answer to this old question: Why is it easy for feces to be washed away from the water in one case, while it continues to float in another?

Until around the 1970s, experts determined that this was due to the large amount of fat in the feces. Furthermore, its excess in the feces (more than seven grams per day) - fatty laxatives - indicates that digestive and absorption processes are violated. However, even healthy people, more than 10% of feces float, which has nothing to do with any particular pathology, according to scientists. Previous studies have shown that the so-called difference in feces float is also related to the amount of gas. However, it is unclear why some people's excretions contain more gas and have greater buoyancy than others' excretions?

According to the author of a new paper published in the journal Scientific Report , feces are an excellent sample for studying gut microbial communities. They represent the largest microbial library, about 100 billion per gram. In a healthy adult, the intestinal gases produced by endogenous microorganisms—especially methane , hydrogen sulfide , and ammonia—only tiny amounts of gases formed in the intestines every day (mainly oxygen , nitrogen and carbon dioxide ). Due to the high density of microbiomes, colon is the main source of endogenous gases, and microbiome fermentation contains foods that are difficult to digest carbohydrate .

These fermentation gases accumulate and are regularly discharged from the body, but may also be retained in fecal biomass, thereby reducing the specific gravity of feces. Therefore, feces weight is affected by lifestyle, diet, water and gas components, and intestinal flora .

When examining the microbiome of sterile mice living in sterile chambers, scientists "luckily" discovered that these laboratory rodents and their relatives had gut bacteria in the feces, which behaved differently in water. It turns out that mice that are not raised under sterile conditions have much lower excretion than are important, so they will swim rather than drown.

"We use these differences to test a new approach, namely levô in fimo (LIFT) was tested to distinguish fecal pellets that were sinking in sterile mice from stool particles floating in mice colonized by gut bacteria. Scientists say that by introducing microorganisms into the intestinal rodents, we were able to change the properties of the fecal tract from "sinking" to "floating".

illustrations show the role of the intestinal microbiome in "fecal levitation" in mice

From this, they concluded that "fecal levitation" is related to the properties of the microbiome and the microorganisms themselves - some microorganisms produce more gas than others.

Intestines in healthy mice contain 37 The main species of bacteria, which affect the host's metabolism and immune system. Bacteroidetes, Gram-negative anaerobic rod-shaped bacteria, is one of the main genera in mouse and human fecal samples. It is representative of this genus, including B. ovatus and B. Fragilis, they produce hydrogen and carbon dioxide, while the former still causes human flatulence.

"Hydragon analysis of mouse feces revealed four gas-producing species of the genus Bacteroidete . In fact, we selected Bacteroides ovarice as the most representative species in our analysis. In addition, we also found Bacteroides fragile ,” the researchers explained.

Of course, more research is needed to better define the different microbial communities that produce more gases, and to understand how many of them become the decisive factor in the buoyancy of rodents and humans. In addition, there is an open question: Are all the above related to functional enteropathy ?