抄録
Chemical changes in the lactose-enriched media were investigated. Glucose was selectively utilized initially, then residual lactose was utilized after a fairly long adaptation period. A stational phase at about pH 8.0 was observed during lactose utilization. A marked increase of mycelial growth was observed in the initial stage of the lactose-utilizing phase. Comparatively rapid and durable formation of vitamin B_<12> was obtained by the lactose enrichment. An accelerated fermentation was resulted by forced aerations in jar fermentor. Some characteristic changes were observed in pH, mycelial growth and vitamin B_<12> liberation in the medium.
