With periodically refreshing the culture medium, a high expansion fold of 60 77 was achieved in each passage.
However, in order to achieve a vitrifiable medium, a high concentration of permeable cryoprotectants must be employed, and the incorporation of high molecular weight compounds should also be considered.
By growing S. thermophilus 4F44 in the newly designed YLUNi medium, a high quantity of the soluble form of PrtS could be produced that could be directly used as the proteolytic agent on sodium caseinate.
When using glucose as a carbon source in the feed medium, a high specific growth rate (corresponding to a high dilution rate) reduces the flux distribution to the pentose phosphate pathway, which might lower the NADPH concentration (Frick and Wittmann 2005).
If purified VacA is added to cells in culture medium, a high number of vacuoles emerge inside the cells [ 3, 4].
In pHi-alteration experiments, 40 μM di-methyl amiloride (DMA) was added to the medium to produce intracellular acidification, and a Cl--free medium, a high pH (>8.3) medium, or a combination of both, were used for intracellular alkalinization.
