| This paper focused on the analyzing method of 1,13-tridecanedioic acid (DCA13), the breeding of DCA13-producing strain and its characteristics, the shaking flask experiments, the matter influenced the cytochrome P450 or related enzyme as well as purification of DCA13.Taking Candida tropicalis TSW-1 as original strain, the DCA13-producing strain, where dimorphism of thread-like was observed, was selected after ions implantation induced mutagenesis. The mutant could accumulate 35.75g/L DCA13 in fermented broth. The relations between the survival and dose of Candida tropicalis by different ions implantation, all took "saddle shape" with increasing of ions implanted dose, and the best results was obtained by 40 keV N+ implantation.Titration analysis method was set up for DCA13; the error was less than 1.5%.In fermentation process, dissolved oxygen of broth, concentration of urea and tridecane, concentration of tridecane, the value of pH and cultivating temperature highly affected DCA13 productivity. When using baffled flask, optimal cultural medium was obtained .in optimal fermentation condition, strain age was 42-44h, inoculum was 15%, the value of pH was 7.5-8.0, the cultivating temperature was 3 TC, in this condition, the yield of DCA13 was 50.00g/L.During the fermentation process, the matter, which can influence the cytochrome P450 enzyme activity or related enzyme, greatly affected DCA13 producvity too. Phenyl barbital as well as tridecane can induce cytochrones P450. Acrylic acid and acetate, tween 80, cellblock tridecane benefited the production of DCA13. Using new method of fermentation, by adding the sucrose or tridecane at the latter circulation of fermentation, the yield of DCA13 reached 72.00g/L.Proteins were roughly eliminated from fermented broth by alkaline and heat disposal, through filter, the strains was eliminated. Its color decreased by adding 3% activated carbon when heated. When the value of pH was decreased to 2.0-3.0, white crystal of DCA13 was obtained.
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