铁皮石斛多糖和醇溶性浸出物动态累积规律研究

为了揭示铁皮石斛多糖和醇溶性浸出物含量的动态变化规律, 为铁皮石斛科学采收提供依据。采用苯酚-浓硫酸法和醇溶性浸出物热浸法测定铁皮石斛3个优良品系一至三年生萌条的多糖和浸出物含量。结果表明, 不同采收期铁皮石斛多糖、浸出物含量及其总量均存在极显著差异, 与铁皮石斛的物候密切相关, 其中多糖含量变化与开花密切相关, 醇溶性浸出物含量与新芽形成、萌动密切相关。根据多糖与醇溶性浸出物含量的动态变化, 以多糖为采收目标时在二年生开花前采收, 以醇溶性浸出物为采收目标时以新芽萌动前采收最佳, 以多糖与醇溶性浸出物总量为目标时以春芽萌动至开花前采收为宜。

Variation of polysaccharides and alcohol-soluble extracts content of Dendrobium officinale

To reveal the variation of polysaccharides and alcohol-soluble extract contents of Dendrobium officinale, the polysaccharides and alcohol-soluble extracts contents of three D. officinale strains were determined by phenol-sulfuric acid method and hot-dip method, respectively. The results showed that the contents of polysaccharides and alcohol-soluble extracts and their total content were significantly different among D. officinale samples collected in different periods, and the variations were closely related to the phenology of D. officinale. Additionally, the quality variation of polysaccharides was closely related to the flowering of D. officinale, while the alcohol-soluble extracts was closely associated to the formation and germination of buds. According to the dynamic variation of these two compounds, it is more reasonable to harvest D. officinale at biennials pre-bloom than at specific harvesting month considering polysaccharides content. It is better to harvest before the germination of buds considering alcohol-soluble extracts. While with regards to both polysaccharides and alcohol-soluble extract, it is better to harvest this plant at the period from the sprouting to pre-bloom next year.