沼泽生红冬孢酵母类胡萝卜素合成条件的优化

Optimization of conditions of carotenoid synthesis by Rhodosporidium paludigenum

为了提高红酵母的类胡萝卜素产量,以从水产养殖环境中分离出的8株红酵母菌为实验菌株,从中筛选出产类胡萝卜素能力较强的沼泽生红冬孢酵母(Rhodosporidium paludigenum)CN7.采用单因子实验方法,分别向培养基中添加不同量的番茄匀浆、胡萝卜汁、柠檬酸钠、乙醇,对CN7菌株的类胡萝卜素合成条件进行优化.研究结果显示,培养基中分别添加番茄匀浆、胡萝卜汁、柠檬酸钠、乙醇,均能提高CN7菌株的类胡萝素合成能力,但不同物质对CN7菌株的胡萝卜素合成能力的提高幅度不同,顺序为胡萝卜汁>乙醇>柠檬酸钠>番茄匀浆.培养基中分别添加80 mL/L胡萝卜汁、1.5 mL/L乙醇、6.0 g/L柠檬酸钠、20 mL/L番茄匀浆,CN7菌株的类胡萝卜素含量分别达到342.82、280.00、255.62、239.19μg/g,较初始值的170.11μg/g分别提高101.5%、64.6%、50.3%、40.6%.上述结果表明,胡萝卜汁对CN7菌株合成类胡萝卜素的促进作用最明显,在后续发酵中可在培养基中添加适量的胡萝卜汁以提高菌株的类胡萝卜素产量.

In order to improve the carotenoid production of Rhodotorula,the carotenoid contents of eight Rhodotorula strains isolated from aquaculture environment were evaluated,and the strain Rhodosporidium paludigenum CN7 with the strongest ability of producing carotenoid was screened out.Single factor experiment was employed to optimize the carotenoid synthesis conditions of strain CN7 by adding different content of tomato homogenate,carrot juice,sodium citrate and ethanol,respective-ly.The results showed that the addition of the above four substances to the culture medium could significantly improve the carotenoid synthesis ability of strain CN7,but different substances had different effects on the carotenoid synthesis.The order of influence was carrot juice>ethanol>sodium citrate>tomato homogenate.When 80 mL/L carrot juice,or 20 mL/L tomato homo-genate,or 6.0 g/L sodium citrate,or 1.5 mL/L ethanol was added to the culture,the carotenoid contents of strain CN7 were 342.82,280.00,255.62,239.19μg/g,respectively,which were 101.5%,64.6%,50.3%,40.6%higher than the initial value 170.11μg/g,respectively.The results suggested that carotenoid content of strain CN7 was increased greatly by carrot juice,so the appropriate amount of carrot juice should be added to the culture medium to get higher carotenoid yield.