Agitation-aeration studies on coenzyme Q10 production using Rhodopseudomonas spheroides

Agitation-aeration conditions for coenzyme Q10(CoQ10) production using Rhodopseudomonas spheroides KY8598 were investigated. CoQ10 production occurred under a limited oxygen supply. The relationship between specific respiratory rate Qo2 and the oxidation-reduction potential (ORP) showed the existence of optimal oxygen supply conditions for cell growth and CoQ10 production. However, the behavior of the maximum specific respiration rate (Qo2)max on the production scale differed from that on the pilot scale. The relationship of Qo2/(Qo2)max and ORP could describe the whole scale-up procedure of CoQ10 fermentation. The optimal ORPs were -150 mV for cell growth and -200 mV for intracellular CoQ10 production. Using these parameters, successful CoQ10 fermentation has been accomplished on the industrial scale.