Optimization Of Biosynthetical Conditions Of Resveratrol With Recombinant Escherichia Coli

Resveratrol is one of the plant antitoxin in many plants generated for ultravioletirradiation or pathological conditions of the fungal infection. Resveratrol have beenfound to be highly active in human body, such as promoting activities against a varietyof diseases,including antioxidant, antitumor, antiviral, antibacterial, anti-inflammatoryand immune liver, treatment of cardiovascular disease and with even the potential toslow aging. Resveratrol can be compouded with many applications in medical, healthfood and cosmetics,its market demand is huge. Resveratrol produced in only traceamounts in polygonum cuspidatum and peanut with poor-purity and low addedvalue in products. Besides, resveratrol could be produced through chemical synthesisway in numerous researches, however, the complexity of synthetic lines, highproduction costs and serious environmental pollution are the main disadvantages.Therefore, the plant extraction and chemical synthesis can not for scale production.Atpresent the two kinds of enzyme influence of resveratrol production, STS (stilbenesynthase) and4CL (coumaric acid ligase) were introduced into plasmid thentransferred to Escherichia coli and yeast, add a metabolic precursor substratep-coumaric acid through microbial metabolism to produce resveratrol.In this study,weused the recombinant Escherichia coli obtained as reffered, The used plasmid carryingthe strong constitutive promoter, without inducer add, to ensure the security in theexpression of the enzyme. Through the plasmid extraction and PCR sequencingoperations to determine the accuracy of the engineered bacteria and determination ofplasmid stability.Then we optimized E. coli fermentation medium in the process of production ofresveratrol and transformation conditions by single factor experiments to determine theoptimal conversion medium is YM9medium. Optimal culture conditions are asfollows: The optimal incubation temperature of37°C, shaking speed200r/min,theinitial pH was7.0, the optimal substrate added is resuspended add, add optimalsubstrate concentration of1.2g/L, the optimum resuspended time prior to there-election of cultured10h. During the experiment, resveratrol liquid detection systemwas established: C18column (250mm×4.6mm,5μm), mobile phase: acetonitrile:water=40:60(0.1%acetic acid), VVD306nm, flow rate of0.5mL/min column temperature of25°C, injection2μL.In all these optimal conditions, resulted in a finalimproved titer of0.6g/liter resveratrol.Finally, we will transferredin6L fermentor, the fermentation process through theoptimization of the conditions in the tank to achieve the industrialized production ofresveratrol.