PROTEASE BIOSYNTHESIS FROM LACTOBACILLUS SPECIES: FERMENTATION PARAMETERS AND KINETICS

In the present study, 15 strains of Lactobacillus species, isolated from 25 samples of curd, were screened for their ability to produce extracellular protease. The proteolytic activities of these strains based on casein hydrolysis showed a variation of 1.26–5.80 U/mL with Lactobacillus IH8 showing a maximum of all. Different cultural conditions for enhanced production of protease by Lactobacillus IH8 were optimized. It was found that optimal conditions for the production of enzyme were an incubation temperature of 35C and a medium pH of 5.5. The maximum proteolytic activity of Lactobacillus IH8 (7.28 U/mL) was achieved after 48 h of cultivation. The kinetic parameters such as product yield coefficient (Y p/x), growth yield coefficient (Y x/s), specific product yield coefficient (qp) and specific growth yield coefficient (qx) also revealed that the values of experimental results were highly significant when analyzed kinetically.