Continuous production of polygalacturonases using wheat flour in a surface culture fermentation

The possibility of continuous production of polygalacturonases (PGases) by a strain of Aspergillus awamori was investigated.. The wheat flour acted as a good substrate for the cultivation of the microorganism and PGases were produced in surface culture fermentation. The fermentation started in batch mode until the medium was covered by the mycelia of the microorganism and after that it turned to continuous mode by introducing the fresh feed. The process continued for 34 days. The thickness of the microorganism layer on the surface of the liquid medium became almost constant after about one week. The production of PGases, however, continued throughout the experiment. The maximum exo-polygalacturonase (exo-PGase) and endopolygalacturonase (endo-PGase) activities of 1.2U/mL and 0.014U/mL were obtained respectively. An increase in production was observed when a similar system was used with a line for medium recycle. Lowering the residence time to 12 hours decreased the exo-PGase and endo-PGase activities.

کلیدواژه ها:

Polygalacturonase ، Aspergillus awamori ، Wheat flour ، Surface culture fermentation ، continuous production