酶法预处理苎麻叶提取总酚酸的工艺优化

Optimization of Extraction Technology of Total Phenolic Acid from Boehmeria nivea by Cellulose Enzyme

为开发和利用苎麻资源,采用酶法对苎麻叶总酚酸的提取工艺进行了研究。用纤维素酶对苎麻叶进行预处理,以单因素试验为基础,对总酚酸提取率进行正交设计,用福林-酚比色法于755 nm波长处测定总酚酸含量。结果表明,酶解时pH值为5.0,酶解后在料液比为1∶20(W/V,g∶mL)、温度为70℃、提取时间为2.0 h、提取2次、乙醇体积分数为70%条件下,苎麻叶总酚酸的最佳提取率为0.050%。影响提取率4个因素主次顺序为提取时间>料液比>pH值>温度。该工艺提取率高、步骤简单、成本较低,适合于苎麻叶中总酚酸的工业化提取。

To make further use of Boehmeria nivea,the extraction technology of total phenolic acid was optimized.After pretreatment by cellulose enzyme,the orthogonal test was adopted based on the results of single factor test to check the effect of various factors.The samples were determined by spectrophotometer at 755 nm.The optimum extraction conditions were enzymatic hydrolysis pH 5.0,solid to 70% ethanol ratio 1∶20（W/V,g∶mL）,extracting for 1 h at 50 ℃ twice.The extraction ratio of total phenolic acid under these conditions was 0.050%,which was 35.5% higher than that of non-enzymic treatment.The influencing sequence from significant to common was extraction time ratio of sample to solvent pH temperature.By enzymatic hydrolysis pretreatment,the extraction yield of total phenolic acid was improved distinctively.The technology was suitable for industrial production.