Characteristics of Ephedrine and Pseudoephedrine Biosynthesis in Recombined Yeasts and the Effects of L-Phenylalanine in Alkaloids Biosynthesis

Objective:Investigation on the characteristics of ephedrine and pseudoephedrine biosynthesis in 12 recombined yeast strains and the effects of L-phenylalanine in alkaloids biosynthesis.Method:Used of glucose as the carbon source,NaNO3 as the nitrogen source to carry on culture to the recombined yeasts,otherwise added the L-Phe of 5mgs/L under the same culture condition.The l-ephedrine and d-pseudoephedrine in the culture liquid of the recombined yeasts were analyzed by the RP-HPLC.Result:After culturing in liquid medium for 72h,extracellular l-ephedrine and d-pseudoephedrine concentrations of 18.85 mg/L and 4.11mg/L,respectively.The addition of the L-Phe to culture medium substantially changed the amount of l-ephedrine and/or d-pseudoephedrine produced by the recombined yeasts.Conclusion:The results of the regulation on L-Phe to the l-ephedrine and d-pseudoephedrine biosynthesis in recombined yeasts would be valuable for further investigations of genetical diversity.