Producing Lycopene By Fermentation

Lycopene is one of the important caronenoids. It is found primarily inthe all-trans configuration in the nature, which has 11 conjugatedcarbon-carbon double bonds. Lycopene has predominantly functions ofquenching singlet oxygen, scavenging of free radicals and inducing thecommunication between cells, so it could act great roles on preventingcancer and atherosclerosis. At the same time, the producing technologies,especially fermentation, have been studied. Fermentation is one of potential methods for producing lycopeneindustrially by Blakeslea trispora . The culture medium, the conditions offermentation, the choices of inhibitor, the influence of modulators andmycelial morphology have been investigated. The results showed that the best basal medium was listed as fellow:glucose10g/L, corn starch30g/L, corn steep liquor60g/L, potassiumdihydrogen phosphate 0.5g/L, magnesium sulfate0.25g/L and thiaminehydrochloride0.5mg/L. The optimized fermentation mediums was cornstarch40g/L, corn steep liquor40g/L, cottonseed oil 50ml/L, potassiumdihydrogen phosphate 0.5g/L, magnesium sulfate0.25g/L and thiaminehydrochloride 0.5mg/L . The flask cultures were incubated at 28℃ for120h under the condition of pH6.5, 250rpm,column of incubation 10%, IIIand the ratio between plus and minus 1:10. The yield of β-carotene couldreach 180mg/L when adding β -ionone , isonicotinoylhydrazine andsuccinmide as the inductors of the biosynthesis of β -carotene.Furthermore, The yield ofβ-carotene was up to 830mg/L through thefermentation by mutants which was attained through physical and chemicalmethods. Some heterocyclis substances such as pyridine and its ramificationtotally inhited the cyclization reaction of the lycopene cyclase but inducedthe production of very important quantities of lycopene. The study showedthat the role of inhibitor of pyridine's ramification was more effective thanof pyridine itself, and found that the lycopene could attain 400mg/L whenadding 1g/L tobacco dust. The modulator could make different effect on fermentation.triton-X100 has little effect on fermentation, but span-20 and β-iononecould enhance the productivity of lycopene significantly. The content oflycopene in the medium increased 3 times of the control experiments byadding 1g/L span-20. Mycelial morphology was exploited a great influenceto the metabolites of fungi. The effect of the mycelial morphology onproducing lycopene of Blakeslea tripora was also investigated. The resultsindicated that pellets has little role on fermentation when adding keroseneand triton-x100,However, The content of lycopene in the medium couldenhance 3 times of the control experiments by adding 1g/L span-20, IVforming dispersed mycelia with optimizing various external factors at themacroscopic. It is essential to establish a accurate and effective method ondetermining lycopene by HPLC. The relation of content between lycopeneand sudan I was been made.