Study On The Process Of Coenzyme Q₁₀ Fermentation By Rhodobacter Sphaeroides

Coenzyme Q₁₀0 is widely present in biological cells and is an electron transporter in the respiratory chain,which can provide the body with the energy substance ATP.Coenzyme Q₁₀0 has functions such as anti-oxidation,scavenging free radicals,regenerating antioxidants,and regulating cell signal transduction,so it is widely used in medicine,food,health products and cosmetics.This project carried out mutagenesis and selection based on the original strain Rhodobacter sphaeroides CICC 10287;carried out research on the substitutes of carbon and nitrogen sources in the fermentation medium,and optimized the fermentation process;explored and selected coenzyme Q₁₀0 fermentation promotion factors and optimized the amount added.The main results are as follows:?1?Mutation breeding of the original strain Rhodobacter sphaeroides CICC 10287.Atmospheric room temperature plasma?ARTP?was used to carry out mutagenesis and selection of starting strains.The optimized mutation and breeding conditions:ARTP treatment time is 30 s;the minimum inhibitory concentrations of the screenings are substrate is:VK3 10 mg/L,Na2S 400 mg/L,and benzoic acid 200 mg/L.After two rounds of mutagenesis,a mutant strain R.S17 with high yield of coenzyme Q₁₀0 was finally obtained..The coenzyme Q₁₀0 production capacity of R.S17 was stable after 10consecutive subcultures,thus,R.S17 had better genetic stability.The yield of coenzyme Q₁₀?236.7 mg/L?in the final mutant strain R.S17 was 78.6%higher than that of the original strain?132.5 mg/L?.?2?Study on the production process of coenzyme Q₁₀0 by sweet sorghum juice fermentation.The research on the substitute of carbon and nitrogen sources in fermentation medium was carried out.The research shows that sweet sorghum juice can be used as a efficient carbon source substitute for glucose;dry corn steep powder can be used as a cheap nitrogen source substitute for yeast extract.The fermentation process of R.S17 was optimized.The optimal fermentation process conditions were:initial total sugar concentration of sweet sorghum juice fermentation medium 80 g/L,dry corn steep powder concentration 12 g/L,initial pH of fermentation medium7.0,fermentation temperature 30?.Under the optimal fermentation conditions,the yield of coenzyme Q₁₀reached 241.3 mg/L.?3?Optimization of the fermentation medium using sweet sorghum juice.Studies the effects of 6 kinds of different molecular weight yeast mannans?YM40,YM50,YM60,YM70,YM80 and YM90?,8 kinds amino acids?alanine,leucine,arginine,serine,glutamic acid,methionine,glycine and Tyrosine?,5 kinds of surfactants?surfactant op-10,Tween 40,Tween 60,Tween 80 and Span 80?,6 kinds vitamin B?VB1,VB3,VB5,VB7,VB9 and VB12?on the biosynthesis of coenzyme Q₁₀.The results showed that yeast mannan YM90,leucine and glutamic acid can promote the biosynthesis of coenzyme Q₁₀.Orthogonal experiments were performed to optimize the combined addition of the three promoting factors.The optimal concentration was as follows:yeast mannan YM90 0.06g/L,leucine 0.5 g/L,and glutamic acid 0.3 g/L.Under the optimal addition conditions,the yield of coenzyme Q₁₀0 from sweet sorghum juice reached 267.5 mg/L,which was 10.77%higher than that of the control experiment.