Study On Metabolic Regulation Of Lycopene Production By Fermentation Of Mated Blakeslea Trispora

Lycopene is one member of the carotenoid family. Its antioxidant activity is higherthan all the other carotenoid and it has specifc applications in nutraceuticals, medicine andbiotechnological purposes. Blakeslea trispora has been described as lycopene-producingmicroorganisms. The process for lycopene production by mated fermentation of Blakesleatrispora plus (+) and minus (-) strains has been developed. But its yield is not high enoughfor the industrialization. In this paper, the detection method of lycopene and β-caroteneproduced by mated Blakeslea trispora fermentation using HPLC was founded, then thefermentation technology of mated Blakeslea trispora producing lycopene was systematicllystudied and optimized, after which, the metabolic control methods of efficient synthesis oflycopene by mated Blakeslea trispora was investigated, in order to have a substantialincrease in lycopene production. which lay a foundation for the industrial production oflycopene. The main results are as follows.(1) The analysis method of lycopene and β-carotene produced by mated Blakesleatrispora fermentation using HPLC was founded. The conditions of HPLC were as follows.The chromatographic column was Symmetry NH2(150mm×4.6mm,5μm); the eluent was100%of acetonitrile; the flow rate was0.2ml/min; the detection wavelength were472nmand453nm; the injection volume was10μL; the column temperature was roomtemperature.(2) The inoculation conditions of lycopene produced by mated Blakeslea trisporafermentation were: the inoculation ratio of plus (+) to minus(-) was1:2; the inoculationamount was10%. The media components of mated Blakeslea trispora fermentationproducing lycopene were optimized using response surface design. The optimum mediacomponents were:100g/L of Glucose,12g/L of Yeast,3g/L of KH2PO4,3g/L of Na2HPO4and0.5g/L of MgSO4·7HO2. The shaking flask fermentation conditions were further optimized, and the optimum conditions were obtained, with initial pH6.5,180r/min ofrotation speed,90mL of liquid volume in250mL flask,28℃of fermentation temperature.(3) The metabolic control of efficient biosynthesis of lycopene by mated Blakesleatrispora was investigated. The β-carotene production in mated Blakeslea trispora could beenhanced by the addition of oxygen carrier n-hexanem, surfactant Span20and enzymeactivity promoter isoniazide. Then, the lycopene cyclase inhibitor LCI11was added toblock the further cyclization of lycopene into β-carotene, so that the lycopene proportionaccounted for more than95%of the total carotenoids, which increased by14.81times incontrast to the control (1.49mg/L).