What is a beneficial Micro organism, and why is it beneficial?

Lactobacillus in our body prevents yeast infection.

E. coli. Intestinal organism that helps you synthesize vitamins, for one thing.

Beneficial micro organism is a microorganism that have advantage (benefit) for another living organism live.
It is beneficial because they have substance (enzyme, protein, sugar etc) that can give us good advantage and can be commercialize.

There are two kind of way for us to get the benefit from a microorganism :
1. Probiotic : this means we have to consume or use the microorganism mass to get the advantage for it (the whole body mass of the microorganism is the beneficial substance)

2. Prebiotic : we consume or use something that can help the good microorganism (that is already in your body) to produce more good substance (like enzyme etc) for us. (the substance that is produced by the microorganism is the beneficial substance)

Hope that help