乙醇发酵中酿酒酵母辅酶NAD^+及NADH测定方法

Determination of Coenzyme NAD^+ and NADH of Saccharomyces cerevisiae Cells in Ethanol Production

乙醇发酵过程中酿酒酵母细胞辅酶NAD+和NADH质量分数及其比例反映了胞内的氧化还原状态和细胞代谢活性,具有重要的生理意义。作者主要研究了加热萃取、珠磨破碎、反复冻融破碎3种方法对乙醇发酵过程酿酒酵母细胞辅酶NAD+和NADH提取和测定的影响,提出基于珠磨破碎、辅以加酸或碱并加热的萃取模式,以及合适的酶循环反应体系,从而建立了高效的胞内NAD+和NADH检测方法。

Due to the importance of NAD＋ and NADH levels in the yeast metabolism,the determination of intracellular NADH/NAD＋ is a very interesting for ethanol production.In this study,Three NADH./NAD＋ extracting methods,including heating,freeze-thaw cycles,shaking bead,for the disruption and extraction of the NAD＋ and NADH in yeast cells were investigated and compared.Finally an efficient process for extraction and detection of NAD＋ and NADH in yeast cells was established as follows.Yeast cells were disrupted by shaking bead while NAD＋ and NADH were extracted by acid or alkali,then the extracts were detected under the favorable enzymatic cycling system Ⅱ.