| Bacterial Growth Curve: The
schematic growth curve shown below is associated with simplistic conditions known as a
batch culture. It refers to a single bacterial culture, introduced into and growing in a
fixed volume with a fixed (limited) amount of nutrient. Industrial situations involving
MIC tend to be much more complex in nature than such a simplified model.

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Note: viable bacteria = living bacteria
Lag Phase:
Bacteria are becoming "acclimated" to the new environmental conditions to
which they have been introduced (pH, temperature, nutrients, etc.). There is no
significant increase in numbers with time.
Exponential Growth Phase:
The living bacteria population increases rapidly with time at an exponential growth in
numbers, and the growth rate increasing with time. Conditions are optimal for growth.
Stationary Phase:
With the exhaustion of nutrients and build-up of waste and secondary metabolic
products, the growth rate has slowed to the point where the growth rate equals the death
rate. Effectively, there is no net growth in the bacteria population.
Death Phase:
The living bacteria population decreases with time, due to a lack of nutrients and
toxic metabolic by-products.
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