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溶剂提取法中的主要提取方法有哪些?各有何特点?

问答题
2022-04-02 15:34
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正确答案
(1)煎煮法此法简便,大部分成分可被提取出来。但此法对含挥发性、加热易破坏的成分及多糖类成分含量较高的中药不宜使用。
(2) 浸渍法此法不用加热,适用于遇热易破坏或挥发性成分,也适用于含淀粉或粘液质多的成分。但提取时间长,效率不高。以水为提取溶剂时,应注意防止提取液发霉变质。
(3) 渗漉法此法由于随时保持浓度差,故提取效率高于浸渍法。但所用时间较长。
(4) 回流提取法此法提取效率高于渗漉法,但受热易破坏的成分不宜用。
(5) 连续回流提取法是回流提取法的发展,具有溶剂消耗量小,操作不繁琐,提取效率高的特点。实验室主要装置为索氏提取器。

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