响应面法优化乳双歧杆菌Z-1冷冻干燥保护剂配方

Response Surface Methodology for Optimizing the Formulation of Cryoprotectants for Bifidobacterium lactis Z-1

采用响应面法对乳双歧杆菌Z-1冷冻干燥保护剂配方进行优化。通过Plackett-Burman试验与最陡爬坡试验确定影响乳双歧杆菌Z-1冷冻干燥后活菌数的显著因素及最优响应值区间,再通过Box-Benhnken试验优化得到乳双歧杆菌Z-1冷冻干燥保护剂最佳配方。结果表明:海藻糖、蔗糖、L-半胱氨酸盐酸盐添加量是影响乳双歧杆菌Z-1冷冻干燥后活菌数的显著因素;经响应面试验设计建立活菌数和海藻糖、蔗糖、L-半胱氨酸盐酸盐添加量的回归模型,得到乳双歧杆菌Z-1冷冻干燥保护剂最佳配方为海藻糖添加量200.51 g/L、蔗糖添加量46.16 g/L、L-半胱氨酸盐酸盐添加量2.31 g/L,其他成分不变(脱脂乳粉添加量100 g/L、乳清蛋白粉20 g/L、甘油4 g/L、异抗坏血酸钠10 g/L、谷氨酸钠8 g/L)。

This study describes the optimization of the formulation of cryoprotectants for Bifidobacterium lactis Z-1 using response surface methodology(RSM).Using the Plackett-Burman design,trehalose,sucrose,L-cysteine hydrochloride concentration were identified as factors with a significant influence on the viable count of lyophilized Bifidobacterium lactis Z-1.Subsequently,the optimal response ranges of the three factors were determined using the steepest ascent method.The levels of these factors were further optimized using RSM with Box-Benhnken design.As a result,a regression model was fitted into the experimental data.The optimal levels of trehalose,sucrose and L-cysteine hydrochloride were determined as 200.51,46.16 and 2.31 g/L,respectively,while the other ingredients were the same as those in the traditional recipe(skimmed milk powder 100 g/L,whey protein powder 20 g/L,glycerol 4 g/L,sodium isoascorbate 10 g/L and sodium glutamate 8 g/L).