Studies On The Fermentation Production Enzyme Q10 From Purple Thermochromatium Tepidum

Coenzyme Q10 is a kind of ester-group compound with cyclic quinone structure,also known as Ubiquinone?UQ?,which is widely distributed in all living cells,especially in mitochondria.As a component of the respiratory chain,the content of Coenzyme Q10 in the inner mitochondrial membrane is much higher than that of other components of the respiratory chain,and due to liposolubility,it has high mobility in the inner membrane,which is especially suitable to be a mobile electron transporter.Moreover,it is an important factor in mitochondrial energy production.In recent years,the preparation of Coenzyme Q10by microbiological fermentation method has gradually become a research hotspot at home and abroad.For example,Rhodopseudomonas palustris,Pseudomonas denitrificans and Methanomicrobium have become important research objects in the production of Coenzyme Q10,and there are also reports on the preparation of Coenzyme Q10 from Photosynthetic bacteria?PSB?in China.Photosynthetic bacteria is a kind of prokaryotes with photosynthetic system at the earliest stage,widely existing in nature in a great variety.Thermochromatium?Tch.?tepidum?Ttp?used in this study was collected in the Mammoth Hot Springs of Yellowstone National Park in the United States in 1984,which is a thermophilic purple sulfur-philic photosynthetic bacteria with the culture temperature of 48°C to 50°C.Thermochromatium?Tch.?tepidum is a class of harmless Gram-negative bacteria with the earliest photosynthesis system,which can grow in aerobic dark or anaerobic lighting condition,and meanwhile,it is also a class of prokaryotes which can fully ingest the sulfides,organics and other substances in the environment for biosynthesis,widely existing in nature.In this study,the determination method of Coenzyme Q10 was established at first.According to the three determination methods of Coenzyme Q10,namely ultraviolet spectrophotometry,visible spectrophotometry and high performance liquid chromatography?HPLC?reported by the existing literature,This study mainly uses ultraviolet spectrophotometry quantitative determination of Coenzyme Q10.The study found that when the optimum culture temperature was 48°C and the optimum pH was pH 7.2,the yield of CoQ10 was the highest.When pH7.2,bacteria grew best and the yield of CoQ10 was the highest.The extraction result of CoQ10 was the best when Thermochromatium?Tch.?tepidum was in a stable growth phase.The average yield of CoQ10 increased with the increase of biomass and the yield determined in the experiment was 108.5 mg/L.As CoQ10 has two forms,oxidation or reduction,it can be confirmed by adding oxidant?FeCl₃?and reductant?Na₂S₂O₃?.The absorption peak of the sample was 275nm without adding oxidant and reductant,which kept 275 nm after adding oxidant and turned to 265nm after adding reductant.It can be confirmed that the CoQ10 extracted from the experiment was in oxidized form.Furthermore,it was found that the peak value of CoQ10 extracting solution almost remained unchanged at 275 nm after being placed at 60°C for one hour,indicating its thermal stability.The absorption peak of Thermochromatium?Tch.?tepidum CoQ10 remained unchanged in the range of pH1.6-13.0,and the structure was stable.Through the research of this topic,we have successfully extracted Coenzyme Q10 from Thermochromatium?Tch.?tepidum and preliminarily discussed its extraction technology and properties,which provides a new way for the production of Coenzyme Q10.