Food waste from various origins as feedstocks for recombinant protein production by Yarrowia lipolytica using in situ fibrous bed bioreactor

Recombinant proteins (rProts) hold diverse applications and exhibit promising market potential. However, the impediment to their industrial production lies in the high associated costs, notably those related to the medium components. This study focuses on the heterologous production of the lipase B (CalB) from Candida antarctica, used as a case study, from food waste by Yarrowia lipolytica. Various food waste hydrolysates (FWHs) were assessed, and Chinese restaurant FWH emerged as the most suitable feedstock for both cell growth and rProt production. Employing a response surface methodology, the culture conditions and medium compositions were optimised, resulting in a 139.4% increase in lipase production in shake flasks, yielding a titre of 6.32 × 10³ U/mL and a productivity of 65.83 U/(mL·h). The lipase titre and productivity achieved in a 2.5-L stirred-tank bioreactor were subsequently increased by 81.0% and 122.8%, respectively. In an in situ fibrous bed bioreactor (isFBB) with cells immobilised on sugarcane bagasse, a pulsed fed-batch strategy led to further enhancement, reaching a lipase productivity of 265.63 U/(mL⋅h). This represents an increase of 80.7% compared to a similar process using glycerol as a feedstock. This study demonstrates clearly that FWHs can be used for rProt production using Y. lipolytica as a cell factory.