Todd Hewitt broth

Recommended for the cultivation of group A hemolytic Streptococci used for serological studies.

Todd Hewitt broth has been used for the culture of various microorganisms, such as Bacillus subtilis and Streptococcus pneumoniae.

Todd Hewitt Broth is used for cultivation of haemolytic streptococci for different serological tests. This medium has been recommended as an alternative type in epidemiologic studies of group A streptococci as well as pathogenic microorganisms. Todd Hewitt Broth medium is very nutritive by the presence of peptic digest of animal tissue and beef heart infusion. Dextrose stimulates haemolysin production. The medium is well buffered by sodium phosphate and sodium carbonate to neutralize the acid produced during dextrose fermentation. This restricts destruction of antigenic streptococcal haemolysin. It is also found that sodium phosphate has a stimulating effect on the pneumococcal growth. Todd Hewitt Broth can be employed as an alternative to serum broth or horse flesh digest broth for the cultivation of streptococci prior to serological typing.

Components (g/L):
Beef Heart Infusion 500.00
Peptic Digest of Animal Tissue 20.00
Dextrose 2.00
Sodium Chloride 2.00
Sodium Phosphate 0.40
Sodium Carbonate 2.50

We offer two media types: the superior granulated GranuCult^® and the cost-efficient powdered NutriSelect^® culture media, depending on your needs.
The designations basic, plus, or prime are added to indicate the quality control level, from basic quality control to standard QC plus to prime for full regulatory compliance.

Suspend 37 g of Todd Hewitt Broth in 1000 ml of distilled water. Mix well and dispense as desired. Sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes.

GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany

NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany