3P-356 : Medium optimization and CO 2 fixation kinetics of Sulfurovum lithotrophicum 42BKT T

Sulfurovum lithotrophicum 42BKTT is a chemolithoautotroph which uses thiosulfate nitrate ion as an electron donor and acceptor respectively and CO2 as a carbon source. We adopt the CO2 assimilating character of this bacterium to CO2 fixation for reducing anthropogenic CO2. We studied kinetics of CO2 fixation of this bacterium under 0.2 atm and 1 atm respectively using Continuously Stirred Tank Reactor (CSTR). The Monod model successfully described the kinetics of CO2 fixation of Sulfurovum lithotrophicum 42BKTT. The maximum specific growth rate was 0.33 h-1 regardless of CO2 pressure while the Monod constant (Ks) was 0.0379 g Na2S2O3/L and 0.196 g Na2S2O3/L under 0.2 atm and 1.0 atm CO2, respectively. We concluded that when substrates were supplied sufficiently, S. lithotrophicum 42BKTT is not subject to CO2 toxicity.