不同生长龄铁皮石斛茎与叶中总多糖、总生物碱及总黄酮含量的差异

Content differences of total polysaccharides,total alkaloids and total flavonoids from stems and leaves of Dendrobium candidum at different growth ages

采用苯酚硫酸法、酸性染料比色法以及硝酸铝比色法分别测定并比较不同生长龄铁皮石斛茎与叶中总多糖、总生物碱及总黄酮的含量差异,为铁皮石斛资源的充分合理利用提供科学依据。结果表明,不同生长龄铁皮石斛茎与叶中总多糖、总生物碱、总黄酮的含量均有显著差异,其中总多糖主要集中于茎,总生物碱和总黄酮主要集中于叶;总多糖含量以2年龄茎最高,为35.32%,总生物碱含量以1年龄叶最高,为0.036%,总黄酮含量以半年生叶最佳,为0.104%;总多糖含量随着生长龄的增加而逐渐减少;3年龄以内的总生物碱和总黄酮含量明显较高,且不同龄之间含量差异较小,而当植株生长至4、5年龄时,其总生物碱及总黄酮的含量明显较低。铁皮石斛茎与叶中各含有较高的不同有效成分,茎和叶均可作为药用资源加以充分利用;为获取最佳效益,综合考虑生长周期、生物量及药用成分含量等因素,人工栽培的铁皮石斛以3年龄内采收为宜,不宜栽种4年以上。

To provide scientific basis for making full use of Dendrobium car^didum resources, content differences of total polysaccharides, total alkaloids and total flavonoids from stems and leaves of D. candidum at different growth ages were determined using phenol vitriolic method, acid-dye and Al （NO3）3 colorimetric method. Results showed that there were significant differences in the contents of total polysaccharides, total alkaloids and total flavonoids from stems and leaves of D. candidum at different growth ages. Total polysaccharides mainly concentrated in stems, but total alkaloids and total flavonoids mainly concentrated in leaves. The highest content of total polysaccharides was about 35.32% for stem of two-year D. candidum, but the highest content of total alkaloids was about 0.036% for one-year leaf, and the highest content of total flavonoids was about 0.104% for half-year leaf. Content of total polysaccharides gradually decreased with growth age, and contents of total alkaloids and total flavonoids of D. candidum in three years were significantly high. When the growth age reached four or five years, the contents of total alkaloids and total flavonoids were significantly low. Each stem and leaf of D. candidum contained different active ingredients, so both of them could be used as medicinal resources. In order to obtain the best benefit and considering the growth cycle, biomass and medicinal ingredients and so on, the appropriate time for artificial-cultivation of D. candidum was three years and not more than 4 years.