Kinetic analysis of alkaline protease production at different substrate concentrations by Bacillus licheniformis - NCIM 2042 in stirred tank reactor

Abstract

Alkaline protease production was studied in a batch stirred tank reactor at different initial casein concentrations in the range of 20, 30, 40 and 50 g/l by Bacillus licheniformis NCIM-2042. Protease production was observed during the bioreactor operation substrate utilization, protease formation and biomass growth was estimated. With the variation of initial casein concentration on the levels of 20, 30, 40 and 50 g/l, the protease production pattern was changed respectively at the end of 72 hours of bioreactor operation. As the concentration of limiting substrate increased, the protease production was found to decrease. The Ks value was found to be 23.361 g/l, Ki is 0.2647 g/l and ?m is 60.65, hr-1. A maximum of 3.3681 U/ml.hr protease product formation rate could be achieved as calculated by the Vm value. The Km value is the saturation constant or Michaelis constant of the product formation kinetics, the Km value in the present study was 2.32E-08.