School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.
School of Pharmacy, Xinxiang Medical University, Xinxiang, China.
J Pharm Biomed Anal. 2020 Jun 5;185:113235. doi: 10.1016/j.jpba.2020.113235. Epub 2020 Mar 5.
Polysaccharides have broad bioactivities and are major components of water decoction of herb formulae. However, the quality control of polysaccharides remains a challenge. Oligosaccharide-fragment approach has been considered in elucidating chemical structures of polysaccharides, but never been used for quantitation. Using reference chemicals and a real sample Danggui Buxue Tang (DBT) in this study, an oligosaccharide-marker approach was established to quantify specific polysaccharides. Firstly, linear relationships between parent polysaccharides and hydrolysis-produced daughter oligosaccharides were verified using reference polysaccharides. Then in case of DBT, two fluorescence-labeled oligosaccharides with high specificity to individual parent polysaccharides were selected as markers. They were easily isolated and identified. Their potential in quantification of parent polysaccharides were satisfactorily validated in terms of linearity (r≥0.99), repeatability (RSD ≤ 8.4 %), and spike recovery (≥80 %). This method could be a promising approach for quality assessment of polysaccharides in herbal formulae.
多糖具有广泛的生物活性，是中药方剂水提液的主要成分。然而，多糖的质量控制仍然是一个挑战。寡糖片段法已被用于阐明多糖的化学结构，但从未用于定量。本研究使用参考化学物质和真实样品当归补血汤（DBT），建立了一种寡糖标志物方法来定量特定的多糖。首先，使用参考多糖验证了母体多糖与其水解产生的寡糖之间的线性关系。然后，针对 DBT，选择了两种对单个母体多糖具有高特异性的荧光标记寡糖作为标志物。它们易于分离和鉴定。从线性关系（r≥0.99）、重复性（RSD≤8.4%）和加标回收率（≥80%）等方面来看，它们用于定量母体多糖的方法是令人满意的。该方法有望成为中药中多糖质量评估的一种有前途的方法。
