help with saccharomyces glucose batch fermentation setup
Posted 02 February 2009 - 01:06 PM
Posted 02 February 2009 - 04:41 PM
Posted 03 February 2009 - 06:45 AM
See what you can come up with GeorgeWolff's suggestion. Good luck!
Posted 03 February 2009 - 10:33 AM
Sorry - it sounds pretty casual. 5% glucose and what? What you may be doing ot exhausting the oxygen - forcing the yeast into anaerobiasis and growth under those conditions can't persist without supplementation of fatty acids. Try adding some tween 80.
oh sorry, I should've had more information. It has 5% glucose, Difco yeast nitrogen base (without amino acids; with essential vitamins and inorganic salts) and amino acid mix (dropout mix). This experiment is basically to test our best engineered ethanol producing strain before we start with continous growth in a fermentor. We dilute to measure OD if it ges over 2. We also tried to buffer and start at a pH of 6.5, 6 and 5.5 but it didn't make much difference. The cells get to OD 1.4 in 12 hrs, 4.4 in 24 hrs, 4.4 to 5 in 48 hrs and remain about the same at 56 hrs.
Edited by tnad, 03 February 2009 - 10:41 AM.
Posted 04 February 2009 - 04:18 PM