From ActinoBase

Lennox Broth

Known as Lennox Broth (or sometimes, mistakenly, as Luria-Bertani medium), this rich medium is used routinely for growth of Escherichia coli. There are several variants on this medium, with differing amounts of NaCl; glucose may also be added, as in the original recipe (Bertani 1951).


Per litre:

  • 5g Yeast Extract
  • 5g NaCl
  • 10g Tryptone
  • Up to 1L dH2O


  1. Add 5g Yeast Extract, 5g NaCl and 10g Tryptone to a beaker
  2. Add 800ml dH2O and stir until all solids are fully suspended
  3. Make up to 1L with dH2O
  4. For solid media, add 4g agar per 200ml LB
  5. Autoclave

-NaCl Lennox

Per litre:

  • 5g Yeast Extract
  • 10g Tryptone
  • Up to 1L dH2O


  • Routine growth of Escherichia coli
  • Checking for contamination in Streptomyces spore stocks or cultures


This is the Lennox formulation, with 5g/L NaCl. Alternatively, 10g/L NaCl can be used (Miller formulation) or no salt (-NaCl). The -NaCl (no salt) version of Lennox should be used when using salt sensitive antibiotics like hygromycin: for example, when cloning into pSS170. (Alternatively, DNA or DNB can be used for hygromycin selection.)

To make liquid Lennox medium, omit the agar and autoclave as above.


Lennox, E. S. 1955. Transduction of linked genetic characters of the host by bacteriophage P1. Virology. 1:190-206.