ABSTRACT
Conventional batch culture, in liquid suspension or as biofilm/colonies on agar plates, has been outstandingly successful in providing convenient and inexpensive growth conditions for microbes. It is important to appreciate that there are numerous phenotypes depending on growth conditions. Thus, when culture conditions have been selected, subsequent cell properties have then also been predetermined to a large extent. The classical growth curve in batch culture includes a lag phase in which adaptation and change to a new environment is involved, and logarithmic phase in which the microbes are in balanced growth, with cells replicating exponentially and with reproducible properties along the log-linear line. The concentration of growth limiting nutrient will affect both growth rate and/or the total extent of growth. Control of specific nutrient depletion can lead to increased reproducibility and relevance. For reproducibility culture densities should be well above or below the critical concentration for intercell signaling.
