First formulated by Tartoff and Hobbs as an enriched medium for cultivation of E. coli recombinant strains and to obtain higher yield of plasmid DNA. It contains large amount of tryptone and yeast extract providing additional nutrients and growth factors growth as compared to LB. Glycerol is added in the medium as the carbon source. It is for non-selective culturing of E. coli strains and high yield production of DNA, plasmid DNA and recombinant proteins. With appropriate antibiotics it can be used for selective culturing of strains.