Culture Conditions Affecting Spore Production of Bacillus subtilis var. niger
Abstract: In order to enhance spore production of Bacillus subtilis var. niger ATCC 9372, on the basis of optimal medium, culture conditions, including initial pH、temperature and dissolved oxygen levels on its spore production were examined. Results suggested that the optimal medium composition for spore production was as follows lactose 5g, peptone 5g, NaC1 5g, MnS04·H20 0.4 g, H20 1000 ml, optimal initial pH was 7. 0 and appropriate medium volume was 25 ml in 250 ml flask. The number of spores could reach 3.4 x 107 cfu/m1, and the highest spore formation was 94.4% at 30℃, 150 r/min for 24 h.
Key words:Bacillus subtilis var. niger; growth carve; culture conditions; spore production