What is the monod's equation?

Answer 1

Monod equation describes the relationship between microbial growth rate and the substrate/nutrient concentration. The equation itself is as shown below;

It can be graphically shown as follows

Note that Ks is the substrate concentration at half maximum growth rate coefficient. Therefore it can be stated that Monod plot and Monod equation is very much similar to Micheli's Menton (MM) plot and Micheli's Menton equation used in enzyme kinetics. There are many versions of Monod equation, but all of them are just re-arrangements of the most common version shown above.

However, when analysing kinetic parameters of microbial growth using real data, double-reciprocal versions of Monod plots are usually used in order to linearise hyperbolic data and to minimise amplification of experimental error. A typical double reciprocal version of the Monod plot is shown below. Note that reciprocals of specific growth rate coefficient is plotted as a function of reciprocal of substrate concentrations in a double reciprocal Monod plot.