The Morphological Development of Aspergillus Niger in Tower Fermenter Culture

Abstract

This study deals with the role played by the morphological development of Aspergillus niger M.i during submerged fermentation in tower fermenters. A necessary part of the preliminary work was the improvement of basic tower fermenter designs at laboratory and pilot scale. The fermentation conditions in a tower fermenter constitute a complex multivariate system, and therefore account has had to be taken of a wide variety of variables, each of which may affect or be affected by morphological changes. Features scrutinised include the relationships between morphological form, column design, inoculum characteristics, surface tension effects, mycelial density, mass transfer, suspension rheology, gas flow rate, and medium characteristics. The results are incorporated into a preliminary systems model, an understanding of which allows control of the morphological development of this strain in tower fermenters of various sizes.