Quality Evaluation of Ophiopogon japonicus from Two Authentic Geographical Origins in China Based on Physicochemical and Pharmacological Properties of Their Polysaccharides

Ophiopogon japonicus is widely used as a tonic herb in China. According to the origins, MaiDong of Chinese materia medica can be classified as Zhe MaiDong (Ophiopogon japonicus in Zhejiang), Chuan MaiDong (Ophiopogon japonicus in Sichuan), Duanting Shan MaiDong (Liriope muscari), and Hubei MaiDong (Liriope spicata). In terms of quality control, polysaccharides-based evaluations have not yet been conducted. In this study, microwave-assisted extraction (MAE) was used for the preparation of polysaccharides from 29 batches of MaiDong. HPSEC-MALLS-RID and HPAEC-PAD were employed to investigate their molecular parameters and compositional monosaccharides, respectively. The ability to scavenge ABTS radicals and immune promotion abilities, in terms of nitric oxide releasing and phagocytosis on RAW 264.7 macrophages, were also compared. The results showed that polysaccharides in different MaiDong varied in molecular parameters. All polysaccharides mainly contained fructose and glucose with small amounts of arabinose, mannose, galactose, and xylose. For polysaccharides of Zhe MaiDong and Chuan MaiDong, the molar ratio of Fru to Glc was roughly 15:1 and 14:1, respectively. Zhe MaiDong exhibited better antioxidant and immune promotion activity, and so did that of fibrous roots. The pharmacological activity, however, did not account for the variation in growth years. Finally, indicators for quality control based on multivariate statistical analysis included: yield, antioxidant activity, the content of fructose, and RI signal. It was concluded that MaiDong's fibrous roots had similar components to the root, and their quality was not significantly affected by growth age. This may provide some guidance for the cultivation and use of MaiDong.