银杏叶中有效成分的连续逆流萃取工艺

The continuous countercurrent process of extracting available ingredients from gingko leaf

采用挤压膨化和连续逆流萃取技术对银杏叶中有效成分的提取工艺进行了研究.结果表明,对银杏叶的挤压膨化预处理有助于提高萃取速度,增加物料堆积密度,与粉碎预处理相比,提高工效约4倍;采用w=70%的乙醇连续循环喷淋逆流6级萃取,在m(乙醇)∶m(银杏叶)=5∶1,总萃取时间240min,萃取温度50～55℃条件下,萃取率(以黄酮计)达99%以上,物料运行正常,操作简便,生产稳定.

By means of extrusion-expansion and continuous countercurrent extraction, the process of extracting gingko biloba extract from gingko leaf is studied. The results show that the pretreatment of extrusion-expansion to gingko leaf can raise the speed of extraction, increase the volume density,and enhance work efficiency by four times compared with comminution. Under the conditions of 70%(wt) ethanol as solvent, six stages of countercurrent extraction, at the solvent ratio (m(ethanol)∶m(leaf)) of 5∶1, the temperature 50～55 ℃ and the extraction time 240 min, the extraction rates is more than 99%(based of flavone), the operation is easy, and production is steady.