为探究溶液体系中细胞聚集的有效分散方法,以酿酒酵母(Saccharomyces cerevisiae)ATCC 9080为研究对象,研究了吐温-20、乙二胺四乙酸(ethylene diamine tetraacetic acid, EDTA)、离子强度、pH、低频超声波(50 Hz)对其细胞水溶液中分散指数的影响,对吐温-20、EDTA、超声波3个因素进行正交试验以获得优化分散条件,然后进行酿酒酵母分散前后的分布类型的变化分析。结果表明,酿酒酵母最佳分散条件为,在PBS中添加0.2%(体积分数)吐温-20和8 mmol/L EDTA并超声波处理15 s,可使酿酒酵母细胞在水溶液中分散指数为0.24。处理后细胞在溶液中分布类型由对照组的集群分布转变为规则分布,且在适宜的分散条件下对酿酒酵母细胞活性无影响。
To explore the effective dispersion method of cell aggregates in aqueous solution system, Saccharomyces cerevisiae ATCC 9080 was used as the target strain. The effects of tween 20, ethylene diamine tetra acetic acid (EDTA), ionic strength, pH and low-frequency ultrasound (50 Hz) on its cell dispersion index were researched. Then orthogonal test was designed on tween 20, EDTA and ultrasound to obtain the optimized dispersion condition, and the distribution types of S. cerevisiae was also analyzed before and after dispersion treatment. The results showed that the optimal protocol for the dispersion of S. cerevisiae was under the condition of 0.2% tween 20, 8 mmol/L EDTA and ultrasonicating for 15 s in PBS, which could increase the dispersion index to 0.24 in aqueous solution. The distribution type of cells was changed from cluster distribution of control group to regular distribution. Moreover, there was no effect on the viability of S. cerevisiae under the optimal dispersion conditions.
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