A new chemically-defined medium for Bacillus subtilis (168) NCIMB 12900

J. LEITCH AND P.J. COLLIER. 1996. Most chemically-defined media for the growth of Bacillus subtilis 168 in batch culture are unsuitable for use in nutrient limitation experiments due to either their low cell density yield or their high numbers of added amino-acids. The authors have developed a medium which gives relatively high cell densities and is highly chemically-defined, containing only one added amino-acid. Growth of B. subtilis in this new medium was observed over time using optical density measurements at 470 nm. The growth curve exhibited entry into exponential phase after only 1–2 h and stationary phase after 8 h. Cell density yields and comparison of growth rates with B. subtilis grown in Fang and Demain Medium (1989) suggest that this new medium is highly suitable for the growth of this micro-organism under both normal and nutrient limited conditions.