培养方式对富硒产朊假丝酵母性能的影响

在摇瓶和5 L发酵罐水平上分别考察亚硒酸钠浓度及其添加方式对高性能(高有机硒含量和高谷胱甘肽含量)富硒产朊假丝酵母制备的影响.结果表明:亚硒酸钠添加质量浓度为15 mg/L时,产朊假丝酵母具有较好的富硒效果,但一次性添加对酵母细胞有较大的毒害作用.采用分批次添加亚硒酸钠的方法获得了较好的制备高性能富硒产朊假丝酵母的培养方式:发酵起始添加L-蛋氨酸10 mmol/L,并在发酵过程的12和15 h分别添加亚硒酸钠10和5 mg/L.在此培养方式下,产朊假丝酵母胞内谷胱甘肽和有机硒含量分别达到172.3 mg/L和1194 μg/g.

Effects of cultivation modes on performance of selenium-enriched Candida utilis

The effects of sodium selenite concentration and addition mode on the preparation of selenium-enriched Candida utilis with high performance(high organic selenium content and high glutathione content) were investigated in flasks and a 5 L fermentor,respectively.It was found that efficient selenium enrichment in C.utilis could be achieved under the sodium selenite concentration of 15 mg/L,but one-shot addition of sodium selenite with high concentration had poisonous effect on yeast cells.Accordingly,a better culture mode for efficient preparation of selenium-enriched C.utilis was obtained with batch addition of sodium selenite as follows:10 mmol/L L-methione was added at 0 h,and 10 and 5 mg/L sodium selenite was added at 12 and 15 h,respectively.Under this culture mode,glutathione of 172.3 mg/L and organic selenium content of 1 194 μg/g could be achieved within the selenium-enriched C.utilis.