从耐辐射球菌发酵液中提取类胡萝卜素方法的研究

Study on the Extraction Methods of Carotenoids from Fermented Liquor of Deinococcus Radiodurans

对耐辐射球菌(Deinococcusradiodurans)发酵液制取类胡萝卜素的提取方法和发酵培养条件进行了初步研究。用有机溶剂溶解菌体细胞并萃取得到类胡萝卜素;采用正交实验对发酵培养基的成分、配比进行了优化。结果表明,以甲醇为溶剂的提取效果最好,成本较低,因此采用甲醇作为提取类胡萝卜素的溶剂。4种天然培养基发酵制备类胡萝卜素的实验结果表明,以豆饼粉培养基的效果最佳,表现为菌体生物量最大,同时类胡萝卜素的产量也最高,是蛋白胨酵母提取物葡萄糖(TGY)培养基的1.563倍。正交实验的结果说明,改变各因子(添加碳源、氮源,pH值)的水平均能显著地影响耐辐射球菌的类胡萝卜素产量(添加葡萄糖和硝酸钠分别比豆饼培养基提高类胡萝卜素产量1.763倍和2.018倍)。多因素多水平实验结果表明,以A3B3C1(葡萄糖3g/L,硝酸钠1.5g/L,pH=6.0)组合的效果最优,其类胡萝卜素产量达到2.318mg/g。本研究为微生物发酵生产天然类胡萝卜素提供了一种新的可行的微生物资源,也为利用耐辐射球菌工业化生产类胡萝卜素提供了实验基础。

The extraction methods and fermentation conditions of carotenoids produced from Deinococcus radiodurans were studied in this paper. Carotenoids from fermented liquor of Deinococcus radiodurans was extracted with organic solvents, and the fermentation condition （composition and formula of the medium） for carotenoids production of Deinococcus radiodurans was optimized with orthogonal experimental design. The results showed that among the three organic solvents, the performance of methanol was the best for carotenoids extraction. Considering the cost of solvents, methanol was selected as the most feasible solvent. Among four cuhure medias made of natural products, the medium of bean cake was best for Deinococcus radiodurans growth and carotenoids production was 1.563 times higher than that of TGY. The results of orthogonal experiments showed that the addition of carbohydrate and nitrogen compound and pH value were beneficial to improve carotenoids yield. Addition of glucose and sodium nitrate could increase the carotenoids yield of Deinococcus radiodurans by 1.763 times and 2.018 times higher than the control （bean cake medium） . The results of multi-factor-and-multi-level experiments showed that the concentration changing of glucose, sodium nitrate and pH affected the carotenoids yield remarkably and the sample of A3B3C1 containing 3 g/L of glucose and 1.5 g/L of sodium nitrate, pH 6.0 was the best among all samples, and its output of carotenoids reached 2.318 mg/g. So it is a feasible method of extracting natural carotenoids from the fermented liquor of Deinococcus radiodurans, and it provides experimental basis for industrialization production of carotenoids from Deinococcus radiodurans.