THE INFLUENCE OF SHEAR-STRESS AND ITS REDUCTION IN THE PRODUCTION OF SACCHARIFYING ENZYME FROM SHOCHU DISTILLERY WASTE-WATER BY ASPERGILLUS-AWAMORI VAR KAWACHI

The effects of shear stress in the production of saccharifying enzyme from shochu distillery wastewater by mold were investigated. From the results of measurements of leaked intracellular nucleotides in cultures subjected to agitation, it was confirmed that the 'filamentous form' of Aspergillus awamori var. kawachi, which could be obtained by a 48-h preculture, was affected by shear stress much more strongly than the 'pellet form', which could be obtained by a 24-h preculture. Production of saccharifying enzyme in jar-fermentor cultures was examined using the filamentous or pellet form of the fungus. In the case of the pellet form, the saccharifying activity reached 113 U/ml after a 3-d cultivation at 600 rpm, while in the case of the filamentous form of the fungus it was only 36 U/ml, with a maximum at 400 rpm. The pellet form of the fungus was thus superior to the filamentous form in jar-fermentor culture from the standpoint of high specific saccharifying activity as well as in its resistance to shear stress.