Extractive fermentation using aqueous two-phase system (ATPS), provide an alternative approach for enhanced production of protease as cells and product partitioned into two different phases and so it overcomes the limitation of product inhibition .
Partition coefficients were determined in each system and the best partitioning system was chosen for extractive fermentation of Bacillus cereus for enhanced protease production.
Extractive fermentation of B.cer in ATPS for the production of alkaline protease
All the three molecular weights of PEG were tested for extractive fermentation. Phase system was constructed by weighing requisite amounts of PEG and potassium phosphate (K[H.sub.2]P[O.sub.4] + [K.sub.2]HP[O.sub.4]) in other constituents of production media.
Difference in partition coefficient of system A in each PEG/potassium phosphate system is very high hence PEG 4000/ potassium phosphate system was chosen for conducting extractive fermentation for production of alkaline protease.
Dextran is a costly polymer and for techno-economic reasons do not attract large scale production while PEG 4000 / K[H.sub.2]P[O.sub.4] + [K.sub.2]HP[O.sub.4] can be used for increased production of alkaline by extractive fermentation.