Mortierella Process Parameters Of Fermentation Production Of ARA

Arachidonic acid is an essential fatty acid, one of the ω-6series of important polyunsaturated fatty acidsin human body, with a variety of physiologically active and important role of nutrition. This topic investigatedfermentation production of ARA by the Mortierella isabellinay YZ-124, optimized the fermentation mediumand fermentation conditions, used the ultrasonic assisted organic solvent extraction of fermentation broth ofARA, and optimized the process parameters. At last used urea adduction and silver nitrate silica gel columnchromatography combined with purified lipids and gained the higher purity of the ARA.1. Mortierella isabellina YZ-124fermentation production of ARA medium and culture conditions wereoptimized. ARA production as an indicator to determine the conditions of Mortierella isabellina YZ-124thebest fermentation medium and its culture. On the basis of single factor tests, Orthogonal combination of testingto determined the optimum fermentation medium: glucose as carbon source, yeast extract as nitrogen source,carbon and nitrogen ratio is30:1, pH6, sodium citrate0.2%, potassium dihydrogen phosphate0.2%,magnesium sulfate0.05%. On this basis studied the best culture conditions: culture temperature was28℃,culture time was7d, inoculum size was20%. Under these conditions, the yield of arachidonic acid was2.40g/L.2.Ultrasonic assisted organic solvent extract ARA optimization of process parameters. ARA productionas an indicator, on the basis of single factor tests, response surface analysis was optimized the extractionprocess parameters. By analysis of variance showed that the good fit, various factors on the production of ARAin decreasing order of ultrasonic frequency>ultrasonic time>material/liquid ratio>ultrasonic temperature. Bysingle factor tests and response surface analysis, the optimal conditions for extraction ARA: ultrasonicfrequency was65kHz, ultrasonic time was30min, material/liquid ratio was1:9,ultrasonic temperature was40℃.Under these conditions, the yield of arachidonic acid was2.49g/L.3.Urea adduction and silver nitrate silica gel column chromatography combined with the technology ofpurification of ARA. By urea adduction preliminarily purified lipids, get fatty acids in samples of ureainclusion, where the ARA content was34.69%. Use100g silica gel,10g silver nitrate preparation of silvernitrate silica gel column, In urea inclusion the fatty acid samples with adsorbent ratio of1:20and elution ratewas50r/min column chromatography conditions, eluted with hexane, ARA content of84.23%, improved thanbefore purification of142.81%.