Photofermentative Hydrogen Production by Agar Immobilized Co-Cultures of Purple Non-Sulfur Bacteria

Koku H., Yücel A. M., Eroğlu I., Baysal G.

5th International Hydrogen Technologies Congress, Niğde, Turkey, 26 May - 28 October 2021, pp.58-60

  • Publication Type: Conference Paper / Full Text
  • City: Niğde
  • Country: Turkey
  • Page Numbers: pp.58-60
  • Middle East Technical University Affiliated: Yes


Purple non-sulfur (PNS) bacteria have the ability to produce biohydrogen via photofermentation. This study focuses
on hydrogen production using co-cultures of immobilized PNS bacteria, investigates the possible synergistic effect
of their co-cultures, and the advantages of immobilization. Growth, hydrogen production and substrate utilization of
single-cultures and, double and triple co-cultures of R. capsulatus hup- (YO3), Rp. palustris (DSM 127) and R.
sphaeroides O.U.001 (DSM 5864) were compared using an artificial hydrogen production medium in 150 mL indoors
and outdoors photobioreactors on 40/2 Acetate/Glutamate medium under continuous illumination and anaerobic
conditions. Hydrogen yields were found to be within 1.71-3.21 mol H2/mol acetate and hydrogen productivities were
found to be within 0.0447-0.406 mol H2/(L.h). Additional studies with different temperature, illumination, and
substrate concentration parameters need to be carried out for deeper understanding of the mechanism of hydrogen
production in immobilized co-cultures in order to further improve and standardize hydrogen yields and productivities.