Variations and modelling of oxygen demand in amino acid production
The L-lysine fermentation by Brevibacteria lactofermentum was investigated in this study. The objective was to improve the process performance by manipulating cellular environment conditions. The main factor under consideration was dissolved oxygen concentration (DOC) in the broth. To implement effective process control, a process model was developed based on combined kinetic study and material balances. The process dynamics at the dissolved oxygen tensions (DOTs) of 2%, 5%, 10%, and 20% was analysed. The results showed that inhibition of high oxygen level could occur during the very early growth phase and depressive effect of low oxygen availability was confined to the rest of the process, suggesting that different fermentation stages required different DOTs. Batch experiments were conducted with 3% DOT for the first 24 h, 10% for 24-48 h, and 5% for the rest of the fermentation, and the results were compared with those under 20% DOT throughout. The final L-lysine concentration reached 51.4 g/l compared with 45 g/l; the overall yield increased from 0.300g/g to 0.343g/g; and the productivity was improved from 0.616 g/l/h to 0.633 g/l/h. Also importantly, the low DOT settings required much less energy for agitation and aeration.
Impact and interest:
Citation counts are sourced monthly from and citation databases.
These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.
Citations counts from theindexing service can be viewed at the linked Google Scholar™ search.
Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.
|Item Type:||Journal Article|
|Keywords:||L, lysine, fermentation, dissolved oxygen tension (DOT), modelling, optimisation|
|Divisions:||Past > QUT Faculties & Divisions > Faculty of Science and Technology|
|Copyright Owner:||Copyright 2001 Elsevier|
|Copyright Statement:||Reproduced in accordance with the copyright policy of the publisher.|
|Deposited On:||25 Jan 2008 00:00|
|Last Modified:||10 Aug 2011 17:44|
Repository Staff Only: item control page