PILOT-PLANT PRODUCTION OF PROTEASE BY ALTERNARIA TENUISSIMA

  • 1 January 1967
    • journal article
    • research article
    • Vol. 15  (2) , 319-+
Abstract
Agar slants of a selected Alternaria tenulaslma strain were illuminated to give conidla suit-able for further propagation. For production of protease with an optimal caseolytie activity in the region of pH 8 to 10, the fungus was cultivated In steel fermentors with 6- and 60-liter working capacity. Maximal activity, 1.5 enzyme unitsA, was attained in a medium based on liver after about 60 hr. of cultivation. The protease was secreted parallel with, or slightly after, the main growth phase. The process could be run favorably with a relatively low aeration rate. The pH of the culture decreased during the process from 7.0 to about 6.3. This was the optimal region also when pH was kept constant by automatic pH control. Optimal temperature was about 28[degree]C, which resulted in a maximal productivity of 0.057 enzyme unitsA/hr. during the protease secretion phase. Replacement of the liver in the medium with skim milk, meat scrap, or rapeseed oil meal resulted in a decrease of the protease yield.