Factors affecting broth viscosity and coenzyme Q10 production by Agrobacterium species

Abstract

In the production of coenzyme Q10 (CoQ10) by Agrobacterium sp. the culture broth becomes highly viscous. In an attempt to improve the production process, the effects of chemical and physical factors on broth viscosity and CoQ10 production were studied, using Agrobacterium sp. KY-8593. A particular concentration ratio of sugar to ammonium-nitrogen (NH4−N) in the medium could effectively enhance CoQ10 production without increasing broth viscosity. An increase in culture temperature to between 32°C and 34°C lowered broth viscosity without reducing CoQ10 production. NH4−N concentration and temperature had a correlative effect on broth viscosity. At a temperature of about 33°C, there was a wide range of NH4−N concentration which was optimal for both broth viscosity and CoQ10 production. In optimal conditions with 8% sugar the apparent broth viscosity was reduced to less than 10 pseudo-cP and CoQ10 production was increased to more than 80 mg/l.