Effects of initial maltose concentration, agitation and aeration rates on the production of glucosyltransferase by Aspergillus niger CCRC 31494

The microorganism Aspergillus niger CCRC 31494 can produce an extracellular glucosyltransferase (GTase, EC 2.4.1.24) with a high transglucosylating activity. The maximal enzyme production occurred at initial maltose concentration of 40 g l(-1). The microorganism was also grown in a 5-liter jar fermenter for GTase production. It was found that the optimal agitation and aeration rates were 750 rev min(-1) and 1.0 l min(-1), respectively, and the enzyme production was about 0.25-0.26 units ml(-1).