PhysioFit is a scientific tool designed to i) quantify exchange (production and consumption) fluxes and ii) cell growth rate during (batch) cultivations of microorganisms. Fluxes are estimated from time-course measurements of extracellular metabolites and biomass concentrations. An important assumption is that cells are in metabolic (pseudo) steady-state.
A tutorial is provided with the software.
The latest version (0.9) is available here
Just unpack zip archive somewhere on your disk and open Tutorial.pdf of the newly created directory for more details on installation and usage.