LB is a highly-referenced microbial growth medium used for the cultivation of E. coli. This nutrient-rich microbial broth contains peptides, amino acids, water-soluble vitamins, and carbohydrates in a standard-salt formulation. The addition of agar provides a solid medium for microbial growth.

Components (40g/ 1L H2O):
Tryptone: 10g
Yeast Extract: 5g
NaCl: 10g
Agar: 15g