Study On Biological Transformation Of Phenolic Compounds Hydroxytyrosol In Olive

To construct a recombinant strains having the ability to express 4-Hydroxyphe nylacetate-3-hydroxylase,HHA gene from E.coli BL21(DE3)was amplified and c onnected to the expression vector p ET 28 a,then transformed into competent cell B L21(DE3).The suitable amount of tyrosol was used as raw materials to prepare h ydroxytyrosol in the recombinant bacteria.Thin layer chromatography and gas chrom atography were used respectively to detect the expression of hydroxytyrosol in supe rnatant.Results showed,after SDS-PAGE analysis,two protein bands of 18.5KD a nd 58.8KDa are obtained.;Hydroxyltyrosol was detected by Thin layer chromatogra phy and gas chromatography.Optimize the bioconversion process,to find the opti mal value: PH = 6.5,temperature = 28 ?,the substrate amount = 50 mg/L,the t ime to join the substrate at 20 hours,selection of latent solvent for polyethylene g lycol(volume fraction 0.5%).The hydroxytyrosol conversion rate of 11.2% under t he condition.The expression recombinant strain HHA was successfully build,and t his strain can effectively convert tyrosol into hydroxytyrosol in the cells.