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Astaxanthin ( astaxanthin ) , 3,3 ' - dihydroxy - beta , β' - carotene -4, 4' - dione ( 3,3 ' - dihydroxy- beta , β' -carotene -4 , 4' - dione ) is a carotenoid pigment , stimulate immunity, prevent cancer , eliminate free radicals, antioxidant protection the biofilm and prevention of cardiovascular disease , such as special physiological function in food, feed, cosmetics and pharmaceutical industry more and more people's attention. In this thesis, Fife yeast production of astaxanthin as a research object, the Fife yeast enzymatic broken process and its pigment extracts nature . On the basis of previously optimized medium in the laboratory , based composite enzyme protease , mannanase the Phaffia rhodozyma effectively broken . Added to the fermentation broth fermented for 72 hours after the complex enzyme per liter of fermentation broth 100mg amount of 38 ° C constant temperature hydrolysis 72h, yeast can breakage rate of nearly 90% . The enzymatic Add penetrant can not effectively improve the breakage rate . The 10L fermenter batch fermentation , enzymatic broken enlarge Experimental results show that : yeast at 22 ° C constant pH glucose the - ammonia flow amount of 100mg per liter of fermentation broth plus training 128 h enzyme , the 38 ℃ enzymatic 72 h , pigment The amount of 50ug/mL yeast broken rate of 90.2% . Comparative tests showed that the type of solvent extraction of astaxanthin , preferably acetone extraction . The optimized extraction process as follows: yeast cell with acetone solid-liquid ratio 1:10 , extraction temperature 45 ℃, extraction time 60min , extracted three times . Stability and antioxidant tests showed that compared with the alkaline and acid calorimetry broken from the pigment , the pigment from enzymatic broken strongest free radical scavenging capacity between the acid hot , but the heat and indoor light stability and soda is broken between the sun and the worst stability . Without being drawn broken pigment in the yeast in the environment of oxygen , heat, indoor light stability compared to enzymatic broken the most stable .
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