The protein and peptide-free, chemically defined Hektor minimal culture media were first developed for the in vitro cultivation of kidney-derived human cell lines such as HEK 293T and HEK 293EBNA, then used for the adaptation of serum-dependent Vero cells to serum-free culture conditions. Versions of Hektor media are offered for routine maintenance and cryopreservation and for production of recombinant proteins