Matrix-immobilized yeast for large-scale production of recombinant human lactoferrin

An improved method of producing and purifying large quantities of recombinant human lactoferrin (hLF) in rich culture medium is demonstrated. The host yeast cells were immobilized using macroporous microencapsulation and introduced to a rich medium to facilitate lactoferrin production. The induced and constitutive expression of lactoferrin using the macroporous microencapsulated yeast resulted in a titer of 18.6 mg l(-1), which is a 9-fold increase from the previously reported highest titer. It was further demonstrated that the macroporous encapsulation circumvented the use of selection pressure to maintain cellular plasmids at a high copy number. The purified hLF exhibited anti-bacterial properties and inhibitory activity against various breast, gastric and colorectal cancer cell lines.