Protein Enzymatic Hydrolysis Integrated with Ultrafiltration

Thermolysin was used to hydrolyse serum bovine albumin. The molecular mass and concentration of hydrolysates were identified by SE-HPLC. The substrate pre-incubation at high temperatures (>46°C) contributed to the increase of the hydrolysis rate and final efficiency, but at 70°C a negative effect caused by the aggregation of albumin molecules was noticed. Pre-incubation time is significant up to 0.5 hour.

Strong product inhibition was detected, thus the values of hydrolysis degree obtained in classical reactors were low. The kinetic equation was elaborated and its constant values were estimated.

The data yielded in an integrated bioreactor-ultrafiltration process provides strong evidence that considered enzymatic process could be significantly intensified. The ultrafiltration membrane with a small pores size was selected to take off the products (peptides), including enzyme inhibitors.

The utility of a previously elaborated kinetic model of biopolymer hydrolysis was checked and a qualitative and quantitative description of the proteolysis products was performed. The data gathered suggest that process efficiency and permeate composition depend on the proper selection of dilution rate and the separation properties of the membrane.