Growth and enzyme production kinetics of a heparinase-producing fungal isolate

Heparinases are microbially produced enzymes that degrade heparins, the sulfated glycosaminoglycans, to generate low-molecular-weight heparins (LMWHs). A heparinase-producing fungus, Aspergillus oryzae, was isolated from soil sample. The fungus produced heparinase, both extracellularly and intracellularly, in its late log phase of growth. Heparinase production and growth kinetics was studied in complex protein digest medium, with heparin employed as the inducer. Heparinase activity was found to be dependent on the rate of utilization of heparin during growth. Heparin was taken up rapidly in the initial exponential phase of the growth at a rate of 0.16 g cell(-1) h(-1). Enzyme activity increased at a rate of 1.53 Units h(-1) with the exhaustion of heparin in the medium. Enhancement of enzyme production by 92% was achieved by manipulation of the fermentation conditions and medium ingredients.