earticle

영어

Biological H2 production from free formic acid occurs at ambient temperature and pressure. Based on previous results, hydrogen production phase of Enterobacter asburiae SNU-1 was decoupled from the growth phase. Hence, separation of hydrogen production from cell growth was performed. Hydrogen production in production phase occurs through formate decomposition by formate hydrogen lyase (FHL). FHL is a complex that consists of two enzymes, formate dehydrogenase H (FDHH) and hydrogenase (Hyd). We carefully examined the effects of hydrogen production in formate solution when each cofactor; Mo, Fe and Ni were added to each of the growth medium, respectively. Cell growth was not influenced, however improvement of H2 productions in 10-3 M, 10-4 M and 10-5 M concentrations of each cofactor were observed, in comparison to those without the addition of cofactors. In the presence of 10-5 M each cofactor, on average 47% increase in the hydrogen productivity was noticed and hence the optimum result was demonstrated. Through this, addition of all these cofactors simultaneously to the growth medium is anticipated on bringing about the synergy effect. Therefore, we can infer that cells grown in the presence of cofactors seem to synthesize more FHL which would be more helpful in further increasing the productivity of H2 and commercializing the reformer for PEMFC (proton exchange membrane fuel cell).