白及花花青素微波提取方法的优化

Optimization of microwave-assisted extraction of anthocyanins from Bletilla striata flowers

【目的】采用响应面法对白及Bletilla striata花中花青素的提取方法进行优化。【方法】采用微波萃取和pH示差法提取和测定白及花中花青素,在通过单因素法获得微波功率、甲醇体积分数、提取时间和料液比4个单因素最佳参数的基础上,利用响应面分析法建立二次回归方程,优化花青素最佳提取参数。【结果】所得优化模型条件与实际提取拟合度良好。pH示差法调整为:测定波长530 nm,溶液平衡时间80 min。本研究范围内,4个因素对提取量影响从大到小顺序为微波功率、料液比、甲醇体积分数、微波时间。在微波功率640 W,甲醇体积分数90%,微波时间22 min和料(g)液(mL)比1∶48的条件下,白及花中总花青素提取量为6.68 mg·g^-1,与理论预测值6.83 mg·g^-1基本一致。【结论】优化所得方法可用作白及花中花青素的提取制备,为日后白及花的综合开发利用提供依据。

[Objective]This study is aimed at the optimization of microwave-assisted extraction of anthocyanins from Bletilla striata flowers.[Method]With anthocyanins in B.striata flowers determined and extracted via microwave-assisted extraction and pH Differential Method and the optimum parameters of the four single factors of microwave power,methanol concentration,extraction time and solid-liquid ratio obtained,the study has managed to obtain the optimal extraction parameters of anthocyanins with the quadratic regression equation model established using the Response Surface Methodology(RSM).[Result](1)The conditions of the optimal model fit well with actual extraction;(2)The pH differential method was adjusted to a measured wavelength of 530 nm and a solution equilibration time of 80 min;(3)The impact of the four factors of microwave power,material to liquid ratio,methanol concentration and microwave time on the amount of extraction decrease in a progressive order;(4)With the microwave power at 640 W,the methanol concentration as 90%,the microwave time set for 22 min,and the ratio of material(g)to liquid(mL)adjusted as 1∶48,the total anthocyanin extraction in B.striata flower was 6.68 mg·g^-1,which was basically consistent with the theoretical prediction value of 6.83 mg·g^-1.[Conclusion]The optimized method can be employed for the extraction and preparation of anthocyanins in B.striata flowers,providing a basis for the comprehensive development and utilization of B.striata flowers.