自溶超声波耦合法提取啤酒废酵母中β-1,3-D-葡聚糖

Autolysis-ultrasonic Coupling Extraction of β-1,3-D-Glucan from Waste Beer Yeast

采用自溶-超声波耦合法提取啤酒废酵母中β-1,3-D-葡聚糖。首先以自溶率为考察指标,将单因素和正交实验相结合,结果显示,pH=5.0条件下,质量分数5%NaCl和体积分数1.5%乙酸乙酯混合添加可以最大限度地促进酵母细胞的自溶,从而促进酵母细胞质壁分离。进而,采用超声波法从自溶后收集的细胞壁沉淀中提取β-1,3-D-葡聚糖,以质量分数2%NaOH作超声溶剂,利用Box-Behnken设计考察了超声功率、超声时间和超声次数对葡聚糖提取率的影响,确定最佳提取条件为:超声功率550 W,超声时间33 min,超声次数2次,在该条件下葡聚糖提取率达到50.5%,与纯超声波提取葡聚糖法相比提取率提高了2倍。

Autolysis-ultrasonic coupling method was adopted to extract β-1,3-D-glucan from waste beer yeast. Firstly, single factor and orthogonal test were designed to study the effect of different autolysis promoters on yeast autolysis. The results show that the mixture of 5% （mass fraction） NaC1 ＋ 1.5% （volume fraction） ethyl acetate can effectively promote yeast autolysis. Furthermore, ultrasonic method was used to extract β-1,3-D-glucan from the cell wall deposition harvested after autolysis. The effects of ultrasonic power, ultrasonic time and ultrasonic times were explored in 2% （mass fraction） NaOH solvent by response surface methodology. The results indicate that the optimum parameters were ultrasonic power 550 W, ultrasonic time 33 minutes, and 2 ultrasonic times. Under the above conditions, the extraction efficiency of β-1,3-glucan was up to 50. 5 % , which was doubled as compared with pure ultrasonic method without autolysis pretreatment. Key words： waste beer yeast; β-1, 3-D-glucan; autolysis-ultrasonic ; Box-Behnken ; biological engineering