This document discusses various proteolytic enzymes, including papain, ficain, bromelain, pepsin, rennin, cathepsin, and trypsin. It defines proteolytic enzymes as enzymes that degrade proteins and describes them as mixtures of endopeptidases and exopeptidases. It provides details on the sources and applications of each enzyme. The applications discussed include meat tenderizing, cell culture, cheese production, protein digestion, and more.