艾叶总三萜的提取工艺优化及其抑菌活性

Extraction Optimization of Total Triterpenoids from Artemisia argyi and Its Antibacterial Activity

摘要:

本研究以湖北恩施艾叶为原料，考察溶剂种类、溶剂浓度、提取温度、液固比及超声时间对艾叶总三萜得率的影响。在单因素的基础上，根据Box-Behnken试验设计原理，选取四因素三水平，以艾叶总三萜得率为响应值进行响应面分析，确定最优工艺参数，并运用倍比稀释法研究艾叶总三萜提取物对7种常见致病菌的最小抑菌浓度（minimal inhibitory concentration，MIC），分析了艾叶中三萜类物质的抑菌活性。实验结果表明，超声波辅助提取艾叶总三萜的最佳提取工艺参数为：乙醇浓度72%，提取温度为73 ℃，液固比20:1 mL/g，超声时间42 min。此条件下艾叶总三萜实际得率为6.51%，其中超声时间、提取温度对艾叶总三萜得率影响较大。艾叶总三萜对所选7种致病菌均有较好的抑制作用，尤其是金黄色葡萄球菌和肺炎链球菌，最小抑菌浓度为3.00 mg/mL。本研究提供的提取方法操作简单、结果稳定，且提取物具有一定的抑菌性能，为艾叶总三萜的进一步开发提供科学依据。

Abstract:

The effects of solvent type, solvent concentration, extraction temperature, liquid-solid ratio and ultrasonic time on the degree of total triterpenoids yield were investigated using Artemisia argyi from Enshi. The four factors were further optimized using response surface methodology based on a three-level, four-variable Box-Behnken design. By analyzing the response surface plots, the optimal levels for total triterpenoids from Artemisia argyi were found. And the antibacterial activity of total triterpenoids was explored through testing the minimum inhibitory concentration (MIC) of different components on 7 test bacteria by the double dilution method. Results showed that the optimal process parameters of ultrasound extraction for total triterpenoids from Artemisia argyi were found to be ethanol concentration of 72%, extraction temperature of 73 ℃, liquid- solid ratio of 20:1 (mL/g) and ultrasonic time of 42 min. Under these conditions, the actual total triterpenoids yield was 6.51%, and the ultrasonic time and temperature were significant to the total triterpenoids from Artemisia argyi. The total triterpenoids from Artemisia argyi had certain inhibitory effect on 7 common pathogenic bacteria, especially had inhibitory effects on Staphylococcus aureus and Streptococcus pneumoniae, the minimum inhibitory concentration (MIC) was 3.00 mg/mL. The process was simple and reasonable, while the extraction had a strong broad-spectrum antibacterial effect which provided a scientific basis for deeply research total triterpenoids from Artemisia argyi.