通过预试验和扫描电镜法分析得出超声波提取可提高芥子中硫苷的提取率,进而采用Plaekett—Burman(PB)试验和响应面法研究芥子中硫苷的超声波提取最佳工艺条件,并以硫苷的提取率作为响应值。在单因素试验的基础上,采用PB试验从影响超声波提取的因素中筛选出超声功率和乙醇浓度两个显著因素,在此基础上,通过最陡爬坡试验逼近最大硫苷提取率区域,然后通过中心组合设计试验对显著因素进行优化,得出最佳超声波提取工艺条件为:仪器(超声波细胞粉碎机)参数为超声功率300W、超声工作时间4s(间歇时间6s),提取总时间25min(即超声150次),液料比15:1(mL/g)和乙醇体积分数48%。在此条件下,硫苷提取率为2.902%,与预测值2.894%相对误差为0.276%。这表明PB试验结合响应面法可以很好地优化芥子中硫苷的超声波提取工艺。
The conclusion that the yield of sinigrin can be improved under ultrasound extraction was obtained with the pre - test and scanning electron microscopy analysis, and then the optimal ultrasound extraction conditions of sinigrin from mustard seed were studied. On the basis of single factor tests, ultrasound power and ethanol concentra- tion were identified by Plackett -Burman (PB) design as main factors that influence ultrasound extraction. And the optimal regions were approached by the steepest ascent design. Then using central composite design and response sur- face analysis, the optimal ultrasound extraction conditions were as follows: the instrument parameters: ultrasound power 300 W, ultrasound time 4 s (interval time 6 s), total extraction time 25 min, ratio of liquid to solid 15:1 (mg/L), ethanol concentration 48%. Under this optimum condition, the yield was 2. 902%, which was very close to 2. 894% of prediction value. The result shows that the ultrasound extraction conditions of sinigrin from mustard seed can be well optimized by PB design combined response surface methodology.