%0 Journal Article %A Broderick, A. J. %A Greenshields, R. N. %T Semi-continuous and Continuous Production of Aspergillus niger Spores in Submerged Liquid Culture %D 1982 %J Microbiology, %V 128 %N 11 %P 2639-2645 %@ 1465-2080 %R https://doi.org/10.1099/00221287-128-11-2639 %I Microbiology Society, %X Sporulation of Aspergillus niger was induced in continuous tower fermenters by restricting growth with nitrate limitation. Semi-continuous production of spores was achieved in a single-stage fermentation by alternating full-nutrient and nitrogen-deficient media to the culture. Continuous spore production was obtained in a two-stage fermentation system using the first stage for the growth of vegetative mycelium under optimum conditions and the second, larger, stage for sporulation induction in a constant nitrogen-deficient environment. Spores were produced from much simplified sporulation structures. Using a new sporulation index (Ω), which relates spore numbers produced to the quantity of substrate utilized, the average production efficiency of the two-stage continuous system was shown to be more than twice that of the semi-continuous production system. The tower fermenter was shown to be ideal for controlling organism morphology, thus providing conditions which allowed the development of continuous fungal sporulation. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-128-11-2639