Ferm. # | Agitation regime | | production lag time | qPinit | Average standard |
|---|
DOmin | t(<40% DO) | μmax | max CDW | [h] | [spec. units/g CDW-h] | deviation [%] |
|---|
[%] | [h] | [h-1] | [g/L] | Red | γ–Act | TBP | Red | γ–Act | TBP | Red | γ–Act | TBP |
|---|
14a-c | 900 rpm | 12.7 | 21.2 | 0.275 | 8.17 | 9.2 | 17.5 | 18.7 | 0.030 | 0.008 | 0.045 | 5.8 | 18.8 | 17.3 |
| | | 2.1 | 1.0 | 0.010 | 0.23 | 0.3 | 1.5 | 1.8 | 0.002 | 0.001 | 0.003 |
15a-c | 1100 rpm | 12.0 | 12.2 | 0.298 | 7.47 | 11.0 | 13.7 | 14.7 | 0.032 | 0.010 | 0.047 | 6.5 | 12.3 | 11.0 |
| | | 1.0 | 1.0 | 0.035 | 0.23 | 1.5 | 0.6 | 0.6 | 0.005 | 0.001 | 0.005 | | | |
16a-c | 900/1100/ | 38.7 | 0.7 | 0.260 | 7.67 | 5.3 | 12.7 | 13.8 | 0.033 | 0.013 | 0.058 | 7.3 | 11.3 | 5.9 |
| | 1300 rpm | 8.1 | 1.2 | 0.008 | 0.15 | 1.2 | 0.6 | 0.3 | 0.003 | 0.001 | 0.002 | | | |
17a-c | 50% DO | 50.0 | | 0.254 | 7.20 | 5.8 | 13.2 | 14.7 | 0.033 | 0.013 | 0.065 | 5.3 | 1.5 | 4.5 |
| | | 0.0 | n.a. | 0.017 | 0.36 | 0.8 | 0.3 | 0.6 | 0.002 | 0.001 | 0.005 | | | |
- Reproducibility of determined growth and production parameters in batch fermentations applying different agitation regimes; average values (large font, top) and standard deviations (small italic font, bottom) determined for three biological replicas each. DOmin, minimal dissolved oxygen (DO) during the fermentation run; t(<40% DO), time period where DO was below 40%; estim. μmax, maximum growth rate estimated from the exponential course of the CO2 evolution rate curve between 5 h and 22 h after inoculation; max CDW, maximum cell dry weight; production lag time, time period from phosphate depletion in the medium until pigments were first detected in the culture using the Red/γ-Act/TBP assays; qPinit, initial specific productivity of secondary metabolites determined by measuring the pigment levels in culture samples using the RED/TBP assays and plotting the data as a function of time, linear regression of the initial production data points after production start; average standard deviation, indication of the variance between the biological replicas for the given analyses (calculated as an average value of the standard deviation between three biological replicas based on measurements at all time-points in secondary metabolite production phase (43 h to 79 h), except for those with lower than 10% of the respective maximum value). Cultivations were performed at the given constant agitation from the start, or started at min. agitation (~325 rpm), adjusted automatically to maintain at least 50% DO; 9/11/1300 rpm indicates manual change of constant agitation from 900 to 1100 to 1300 rpm after 21 and 26 h, respectively, to prevent a DO of lower than approx. 50%, agitation was returned to 900 rpm after 45 h.
