Study On Biosynthesis Of Coenzyme Q-10 Using Solanesol From Tobacco As Precursor

The Coenzyme Q10 is a prenylated benzoquinone lipid, and it is alsonamed ubiquinone. The Coenzyme Q10 are found in microorganisms,plants, and the heart, kidney, liver of animals, where they function asredox carriers in mitochondria or in association with respiratory processesof electron transport chains. It is an antioxidant produced naturally. Inthis paper, we studied the purifying technology of solanesol, theidentification and the culture conditions of the CoQ₁₀ producing strain,and the effect of the supplementation of solanesol on the fermentation.Solanesol is the important side chain precursor. We described in thispaper the main three steps performed in the solanesol purifying:extraction, saponification and crystal. Using discard tobacco as rawmaterial, the result suggests that extract by whisk, saponificationemploying KOH 3hr under 60℃temperature, and crystal by ethanolunder low temperature displayed to be the most optimal conditions, togain the 63.85% solanesol. A CoQ₁₀ producing strain was isolated and identified. Themorphological and biochemical characteristic of E03 strain which has thehighest producing capability has been investigated.After comparing its sequence of 16SrDNA gene with GenBank andBiolog system analysis, it could be found that the E03 strain shouldbelong to genus Sphingomonas, and was closest to Sphingomonaspaucimobilis with 98% sequence similarity. So E03 was named asSphingomonas sp. Z JUTE03.The culture conditions affecting Sphingomonas sp. ZJUTE03 cellgrowth and CoQ₁₀ production were studied. The optimal fermentationmedia (g/L) was as follows: glucose 15, (NH₄)₂SO₄ 10, MgSO₄·7H₂O 0.5,Na₂HPO₄ 1.5, KH₂PO₄ 0.5. The optional pH for the formation of CoQ₁₀was 8.0, and the optional temperature was 25℃. The amount of CoQ₁₀was about 36.09mg/L, cultured for 24hr under these optional conditions.The supplementation of solanesol can efficiently increase theproduction of CoQ₁₀ under the optimized conditions: Sphingomonas sp.ZJUTE03 was cultrued for 12h, then 0.75g/L raw solanesol was addedusing anhydrous alcohol as the solvent, and continue to ferment for 12hfor biotransformationl the production of CoQ₁₀ is increased to96.88mg/L.