An initial medium beta cryomodule has just been undergone the first cryogenic tests.
The mESC were exposed to wide ranges of initial medium glucose, glutamine, ammonium, lactate, pH and osmolality conditions.
The medium optimization resulted in a 6-fold increase in xylanase production compared to that of the initial medium.
Intracellular lipase activity and cell mass concentration were respectively 3.2 and 2.4 times greater and cultivation period decreased by 24 h compared with the initial medium.
The medium optimization resulted in a 3.4-fold increase in keratinase production (87.73 U/ml) compared to that of the initial medium (25.9 U/ml).
A final optimisation step, varying only yeast extract concentration, allowed six-fold improvement of the quercetinase activity with respect to initial medium, reaching a maximum activity of 0.708 μmol/min/ml after 9 days of cultivation.
Copper and silicon release following 24 h dissolution increased non-proportionally with Cu-BG concentration in cell culture medium, while calcium levels were decreased below the initial medium concentration.
By employing limited methanol feeding at 0.75 ml min−1 per 10 l initial medium, oxygen consumption was reduced, permitting a lowering of the bioreactor agitation speed from 800 to 400 rpm.
The results of first-order factorial design experiments showed that the liner terms of glutamic acid, citric acid and glycerol had significant positive effects, but the initial medium pH exhibited insignificant effect on γ-PGA production.
The results indicated that several components, including hulled grain of wheat (HGW), sardinella peptone (SP), NaCl, CaCl2, MgSO4, K2HPO4, KH2PO4, agitation, culture temperature and initial medium pH, had significant effects on production.
An initial medium pH 8.0, agitation 200 rpm, incubation temperature 40 °C and inoculum size 1.0% (v/v) were found to be optimal for xylanase production (264.77 IU/ml), after 48 h of incubation.
