Tryptone is a pancreatic digest of casein and used as a nitrogen source in culture media. It is capable of supporting growth of fastidious and nonfastidious micro- organisms. It can also be used for indole production because of its high tryptophane concentration. IBI also recommends Tryptone as casein peptone in media used for detecting bacteria in dairy products, drinking and waste water, and in antibiotic test media.