| Abstract: | The effect of immobilisation of an industrial strain of Bacillus amyloliquefaciens in calcium alginate beads on production of α-amylase was investigated using lactose-based media in shake flasks and in a 0.3 dm3 glass fermenter. Although the microorganism was a good α-amylase producer in batch cultures of free cells, it was unable to produce the enzyme for extended periods either in repeated batch cultures, or in continuous cultivation. In each case, parallel tests with cells immobilised in calcium alginate beads gave still further reduced enzyme yields, and the free cells released into the broth from these beads probably contributed substantially to any amylase produced during these extended fermentations. After prolonged use, the core of the alginate beads accumulated hard insoluble material, with viable immobilised cells confined to a surface layer. |
