Ans 4. Tell me which 3?
Acetic acid bacteria (AAB) are a group of Gram-negative bacteria which oxidize sugars or ethanol and produce acetic acid
Lactic acid bacteria (LAB) are an order of gram-positive, low-GC, acid-tolerant, .... Strains of LAB are the most common microbes employed as probiotics.
A large number of micro-organisms including bacteria, fungi and yeasts have been employed to produce citric acid.
Gluconic acid can be produced by a wide variety of prokaryotic and eukaryotic microorganisms.
Bacterial species of the genera— Gluconobacter, Acetobacter, Pseudomonas, Vibrio.