A-B
They are living, unicellular microorganisms belonging to the empire of prokaryotic, which means that bacteria do not have nucleus.
The bacterial genetic material, consisting of DNA, is in the form of a single chromosome and possibly, plasmids.
C-D
CFU for Colony Forming Unit is the unit for counting the number of live bacteria, each giving rise to a colony in the tested sample. This is the value derived from the viability analysis (microbiology test).
Eating is a universal and daily act that is essential for human survival. Food that we eat contains nutrients, which are vital for our body to function properly. During the digestion phenomenon, the large molecules provided by food are broken down in the digestive tract into nutrients, which will pass into the blood in order to be used by the cells of the organism.
Gut microbiota is an ecosystem in equilibrium that self-regulates permanently. The balance between the different flora of the intestine can break under the threat of aggression. This microbiota imbalance is introduced by the term dysbiosis, as opposed to normobiose.
E-F-G-H
Enterotypes allow individuals to be classified according to their intestinal bacteria.
The bacterial species housed in the digestive tract are uniquely combined and distributed in each human being. Thus, each person has his or her own microbiota.
Holobiont… A mysterious term that has been emerging for the last ten years. What is its meaning?
Humans, animals, plants…. We all have one thing in common: we are made up of a wide variety of micro-organisms (bacteria, yeast, viruses, fungi, etc.). We are “Jamais seul” (never alone), as Marc-André Selosse puts it in his book of the same name: organisms resulting from the evolution of life have always had to deal with microbes.
I-J-K-L-M
You may be already familiar with the microbiota, an organ that is the subject of so much research and is involved in several health phenomena. But do you know the microbiome? How is it defined? How is it different from the microbiota?
The microbiota is defined as all the micro-organisms living on or inside a living being. It consists mainly of bacteria, but also fungi, viruses, protozoa, archaea, etc. The term “microbiota” refers to the microorganisms present, i.e. all the counted individuals.
The intestinal microbiota, formerly called intestinal flora, is an important organ of our body that participates in our health and well-being. It consists of a complex and diverse ecosystem of microorganisms that reside on the surface of the intestinal mucosa : mainly bacteria, but also yeasts and viruses.
N-O-P
It is only in 2013 that the term “psychobiotics” appears. Its creators, clinical psychiatrist Professor Ted Dinan and neuroscientist Professor John Cryan, define it as “live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness”. At that time, they were only applying the definition to a subset of probiotics.
We know the Probiotics, the Prebiotics, the Synbiotics… But have you ever heard of Postbiotics?
Postbiotics mean “after the probiotic”. These are by-products of fermentation processes taking place in the gut. In concrete terms, these are metabolites secreted by living bacteria or released after bacterial lysis.
Prebiotics are non-digestible fibers from our diet. Their goal is to selectively stimulate the beneficial bacteria of our intestinal microbiota.
Prebiotics are mainly short chains carbohydrates (i.e. sugars). After consumption, prebiotics cross the digestive tract without being digested until the colon. They are used as a substrate by the “good” bacteria, which ferment and turn them into short-chain fatty acids such as butyrate, acetate, lactate or propionate.
According to World Health Organization (WHO), probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit to the host.
These microorganisms are mainly represented by bacteria and yeast. They act on the balance, integrity and diversity of the intestinal microbiota, especially in cases of dysbiosis.
Q-R-S
QPS means “Qualified Presomption of Safety”. This is a list serving as a tool to quickly identify risks related to the use of a microorganism. Generally, lactic acid bacteria considered as probiotics have this status.
T-U-V-W-X-Y-Z
The intestinal mucosa serves as a barrier thanks to tight junctions that allow selective passage of molecules.
However, some factors can affect its integrity and modify its tightness. Indeed, enterocytes will secrete zonulin, a protein responsible for the tight junctions separation.
