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Screening from the laboratory preserved bacteria producing bacteria to a coenzyme Q10 XM023, production of coenzyme Q10 reached 18.80mg / L. First analysis by colony morphology and cell microscopy observation, as well as liquid culture with physiological and biochemical characteristics, preliminary judgment Gram-negative bacteria, cells rich in pigments, the typical photosynthetic bacteria. Further 16SrDNA molecular identification techniques, determination XM02316S rDNA sequences and a phylogenetic tree was constructed, and ultimately determine the strain sphaeroides (Rhodobacter sphaeroides). XM023 as the original strain, UV and LiCl two mutation breeding, screened-resistant p-hydroxybenzoic acid, the roxithromycin mutant XM Ⅱ 136, coenzyme Q10 production to 31.79mg / L, a 69.10% increase compared to the original strain, The mutant XM II 136 5 consecutive passages culture, coenzyme Q10 to maintain production in 29mg/L-33mg/L The results show that a trait is more stable, in-depth research and development of fine strains XM Ⅱ 136. XM Ⅱ 136 coenzyme Q10 fermentation optimization, first screened by single factor to determine the best medium carbon source of glucose, a nitrogen source for corn syrup; optimum fermentation conditions: 10% of the inoculum size, initial pH of 6.8, medium amount 50mL/250mL flask; followed by two level Plackett-Burman design filter 9 ingredients in medium affect the fermentation of three important components: glucose, glutamic acid, NaCl,; reuse of response surface methodology the three parts of a three-level optimization to obtain them the best combination of: glucose 34.2 mg / L, glutamic acid 2.42mg / L, NaCl 1.98mg / L,. Through the above optimization process, coenzyme Q10 final fermentation level reached 129.21mg / L, 306% higher than before optimization. The results showed that by analyzing the metabolic processes of the XM II 136 coenzyme Q10 flask fermentation coenzyme Q10 synthesis and cell growth half coupling process. Based on the Logistic equations and Luedeking-Piret equation constructed coenzyme Q10 fermentation bacterial growth, substrate consumption, product formation dynamics mathematical model, the dynamic model of experimental fitting solving the relevant kinetic parameters and, ultimately, the dynamics mathematical equation. The mathematical equations and experimental data can be fit well, preferably describes XM II 136 coenzyme Q10 shake flask batch fermentation process. Different vitamin synthesis of coenzyme Q10, the results show that the most obvious: p-carotene effect, increased by 32.3% compared with the control. VB1, choline chloride, biotin, respectively, higher than that in the control 11.2%, 13.3%, 10.8%; same time, experiments show that the the different additives optimal add time is also different: biotin, B1 is added at the beginning of fermentation better; while p-carotene, the better the effect of choline chloride added in the fermentation process. Soybean oil discovery added to the culture medium, soybean oil, promote the synthesis of coenzyme Q10, 7.6% yield compared with the control. Batch fermentation study of coenzyme Q10, First, the effects of glucose added in shake flask conditions, the impact of the additional amount and an additional coenzyme Q10, results showed that the fermentation 36h supplemented with sugar than sugar fermentation starting to fill effects better complement the total amount of sugar 30g / L, a small number of additional available maximum coenzyme Q10 production 218.78mg / L,. On this basis, the 10L fermenter batch fermentation complement batch fermentation amplification experiments, the results show that: the batch fermentation for the synthesis of coenzyme Q10, is superior to the batch fermentation, the level of the former the coenzyme Q1o fermentation up to 704.9mg / L, the score Batch fermentation (coenzyme Q10 fermentation levels of 358.5 mg / L) 96.6%.
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