Todd Hewitt Broth

Product information

A nutritious broth medium formulated by Todd and Hewitt for the production of antigenic streptococcal haemolysin. Todd Hewitt Broth is also used to cultivate streptococci prior to serological grouping. The use of a fermentable sugar in the formulation leads to the production of acid which would normally inactivate the haemolysin. This is prevented by the inclusion of buffers to maintain the pH of the medium thus preserving the haemolysin, as well as promoting the growth of pneumococci.