Efficient production of coenzyme Q10 from acid hydrolysate of sweet sorghum juice by Rhodobacter sphaeroides

Abstract

In order to achieve efficient bioconversion of biomass-derived sugars, acid hydrolysate of sweet sorghum juice (SSJAH) containing abundant fermentable sugars was used for coenzyme Q₁₀ (CoQ₁₀) fermentation by Rhodobacter sphaeroides CQ-09-1. The synthesis of CoQ₁₀ was facilitated when the initial concentration of total sugar was 80.00 g L⁻¹. And the highest CoQ₁₀ titer was obtained when the pH and temperature were maintained at 7.00 and 30.00 °C, respectively. Moreover, corn steep powder (CSP) was proved to be an efficient nitrogen & salt supplement to SSJAH. Under the optimized conditions, the titer of CoQ₁₀ reached 141.95 mg L⁻¹ in a fed-batch fermentation. The CoQ₁₀ titer reported was about two times higher than that obtained in the previous study using wild strains. This process introduces a potential way to produce CoQ₁₀ using the concept of biorefinery, while making full use of sweet sorghum juice (SSJ).