不同光照条件、不同采收时间对铁皮石斛总多糖、还原性糖以及甘露糖含量的影响

Effects of Different Light Conditions and Different Harvest Time on Total Polysaccharides, Reducing Sugar and Mannose Content of Dendrobium officinale

目的探讨不同采收时间和不同光照条件下铁皮石斛茎和叶中多糖、还原性糖以及甘露糖的动态变化规律。方法苯酚-浓硫酸法测定多糖含量,DNS法测定还原性糖含量,PMP柱前衍生化法测定甘露糖含量。结果铁皮石斛茎中多糖含量在单层遮阴网的条件下含量最高,而叶中多糖含量在全光照的条件下含量最高。叶中还原性糖含量远远高于茎中还原性糖含量。茎中甘露糖含量明显高于叶中甘露糖含量,但是叶中单糖组成较茎中丰富。结论不同的采收时间和光照强度对铁皮石斛的多糖、还原性糖和甘露糖的含量积累有一定影响,适宜的采收时间和光照强度对控制铁皮石斛药材的质量具有重要的实践意义。

Objective To explore the dynamic variation ofbiomass and content ofpolysaccharide, reducing sugar and mannose from Dendrobium officinale at different light intensities and harvest time. Methods The phenol-sulfuric acid method is used to determine the content of polysaccharide, 3, 5-dinitrosalicylic acid （DNS） method is used to analyze the content of reducing sugar, high performance liquid chromatography （HPLC） is used to determine the content of mannose. Results The content of polysaccharide in stem is the highest under the condition of single layer shading network, while the content of polysaccharide in leaf is the highest under the condition of total light. The amount of reducing sugar in the leaf is significantly higher than that in the stem. The content of mannose in stem is significantly higher than that in mannose. But the monosaccharide in the leaf is richer than the stem. Conclusion Different light intensities and harvest time have significant influences on the growth of D. officinale, and the accumulation of polysaccharide, reducing sugar and mannose. Suitable light intensity and incubation time have very important practical significances to produce medical ingredients of D. officinale.