This video is the second in a series of three videos depicting the major stages of industrialscale bioprocessing: fermentation, separation/recovery, and purification. This video describes the process by which a biological product—in this case, molecules of Green Fluorescent Protein (GFP)—is recovered from host e coli cells. The steps of this process are, in very basic terms: (1) separation of cell solids from the broth, (2) disruption of those host cells to release the product contained in them, and (3) isolation of the product through removal of cell debris and other impurities. Tools used to perform these steps include centrifuges, cell disrupters and microfilters.