Effect of dissolved oxygen tension and ph on the production of extracellular protease from a new isolate of bacillus subtilis K2, for use in leather processing
✍ Scribed by Abdul Hameed; Tajalli Keshavarz; Christine S Evans
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1999
- Tongue
- English
- Weight
- 112 KB
- Volume
- 74
- Category
- Article
- ISSN
- 0268-2575
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✦ Synopsis
Scale-up of production of an alkaline protease, previously characterised from a new isolate of Bacillus subtilis for use as a bating enzyme in leather processing, is described. Before large-scale commercial production of the protease is possible, characteristics of the growth of the bacterium and enzyme production in fermenters must be deüned. In 2 dm3 fermenters an optimal speciüc activity of 296 Â 103 U g-1 cell dry weight was obtained after 60 h with the dissolved oxygen tension (DOT) kept above 10% and pH left uncontrolled. Culture pH was 6 on inoculation, falling to 5.3 after 12 h before rising steadily to ¿ 8 at the end of fermentation. DOT was maintained above 10% by agitation in the range 300 to 500 rpm. The same criteria were adopted for scale-up to 20 dm3 but the increase in activity occurred 24 h later.