Anaerobic oxidation of dissolved hydrogen sulfide in continuous culture of the phototrophic bacterium Prosthecochloris aestuarii.
The anaerobic oxidation of dissolved H2S to elemental sulfur was studied at 23 degrees C and pH 6.5+/-0.3 in continuous culture of the phototrophic green sulfur bacterium Prosthecochloris aestuarii. The number of cells formed in the cultures was proportional to the amount of H2S oxidized, and the growth yield was independent of light intensity. The specific growth rate was significantly dependent on the dissolved H2S concentration and light intensity. The kinetic data were analyzed with a rate expression as a function of each rate-limiting factor. Under illumination by white fluorescent lamps, the specific oxidation rate of P. aestuarii reached a maximum of 2.02 x 10(-14) mol-H2S.h(-1).cell(-1) when the dissolved H2S concentration was 2.1 mM at 5000 lx. Simultaneous use of near infrared LED (light-emitting diode) and white fluorescent lamps provided a 35% increase in the maximum specific H2S oxidation rate.
Takashima
T
T
Department of Chemical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan.
Nishiki
T
T
Konishi
Y
Y