铁皮石斛具有重要的药用价值，但其资源有限，因此对其充分开发和利用具有重要的意义。本文利用αL鼠李糖苷酶辅助提取铁皮石斛多糖，通过对酶解温度、酶解时间及加酶量三个因素进行优化，提高铁皮石斛多糖提取率；结果显示，在酶解温度为40  ℃、酶解时间为1 h、加酶量为2.5%时，多糖提取率为38.4%，而不加酶处理多糖提取率仅为21.7%，酶法处理大大增加了铁皮石斛的多糖提取率。同时，运用顶空固相微萃取技术结合气相色谱质谱联用仪（HSSPMEGCMS）分析比较αL鼠李糖苷酶对铁皮石斛挥发性成分的影响；GCMS分析表明，铁皮石斛加酶处理前后共发现31种挥发性成分，主要成分均为己醛、1辛烯3醇、异薄荷醇和3辛烯2酮，并且醛类化合物在加酶处理前后的样品中相对含量均最高，且加酶处理后产生6种新的挥发性成分。该研究结果表明αL鼠李糖苷酶的使用可显著增加对铁皮石斛多糖提取率，并为铁皮石斛挥发性成分的研究和开发利用提供一定的参考依据。

Dendrobium candidum has important medicinal value, but with limited resources, so it has great significance to its full development and utilization. In this study, the extraction of polysaccharide from Dendrobium candidum was assisted by αLrhamnosidase. The extraction rate of Dendrobium candidum polysaccharide was improved by optimizing three factors, including temperature, time and enzyme quantity. The results showed that the polysaccharide extraction rate reached the maximum (38.4%)at 40  ℃, 1 h with 2.5% enzyme quantity and 21.7% without enzyme treatment. At the same time, the effects of αLrhamnosidase on the volatile constituents of Dendrobium candidum were analyzed by HSSPMEGCMS. GCMS analysis indicated  that 31 kinds of volatile components were found and the main constituents were hexanal, 1octen3ol, isomenthol and 3octen2one. The relative content of aldehydes in the sample were the highest and 6 kinds of new volatile components were produced after enzyme treatment. The results showed that αLrhamnosidase has a positive effect on the extraction rate of polysaccharide from Dendrobium candidum, which provides a basis for the research and application of Dendrobium candidum polysaccharides, also gives some references for the research and development of the volatile components of Dendrobium candidum