Iskandaryan, MeriMeriIskandaryanBaghdasaryan, LusineLusineBaghdasaryanMinasyan, ElaElaMinasyanTrchounian, KarenKarenTrchounianAntranikian, GarabedGarabedAntranikianPoladyan, AnnaAnnaPoladyan2025-02-122025-02-122024International Journal of Hydrogen Energy (in Press): (2024)https://hdl.handle.net/11420/54217Cupriavidus necator produces O2-tolerant [NiFe]-hydrogenases (Hyds), and is a valuable biocatalyst for biological fuel cells, while Escherichia coli produces H2 during mixed-acid fermentation. A mixture of curd and cheese whey (CW) was used to explore two-phase growth with C. necator H16 and E. coli. Enhanced biomass, as well as Hyd activity and electrical potential (∼0.65 V) were shown for growth of C. necator in the CW medium with added glycerol. The residual growth medium made available after the cultivation of C. necator and removal of cells was then used for cultivation of E. coli. Maximum fermentative growth of E. coli was attained after 72 h and with a H2 yield of ∼6 mmol/L/g dry whey after 48 h. This study demonstrates the economically viable production of biomass, hydrogenase enzymes and H₂ using cheap, industrially produced whey within the 3R concept.en1879-3487|||0360-319920243R concept | Bioelectricity | Biohydrogen | Dairy industry side-streams | Glycerol | HydrogenasesTechnology::610: Medicine, HealthJournal Article10.1016/j.ijhydene.2024.10.256Journal Article