Isolation and characterization of bacteriocins from fermented food by using the various food isolates tested against different test organisms. Several steps of isolation of bacteriocins is carried out by Agar Well Diffusion Assay Test and preparing the cell free extract by the centrifugation of overnight broths and pouring the cell free extract and the overnight broth of the food isolates tested against the test organisms by a process called overlaying on nutrient agar plates. Standardization procedure was carried out so as to make the test organisms to spread on the Petriplates. Tween20 is used to know whether the bacteriocins are attached to the cell. Microscale Optical Density Assay was carried out on the 96 wells Petri plate. Then the extraction of protein was done by the process of dialysis taking the dialysis membrane to know whether the proteins passes through the membrane or the membrane with holds the protein.