College of Pharmaceutical Science, Soochow University, Suzhou 215123, PR China.
College of Pharmaceutical Science, Soochow University, Suzhou 215123, PR China.
Int J Biol Macromol. 2024 Mar;261(Pt 2):129709. doi: 10.1016/j.ijbiomac.2024.129709. Epub 2024 Jan 28.
The dried root of Pueraria mirifica (P. mirifica) is an edible foodstuff widely used in Asian countries. P. mirifica is known for its high starch content. The isolation of polysaccharides from high-starch plant parts is challenging due to the interference of starch. Therefore, this study aimed to develop a technique for isolating and investigating the structure and activity of non-glucan polysaccharides from P. mirifica (PMP). An effective starch removal process was developed using α-amylase hydrolysis and thorough membrane dialysis. Four non-glucan polysaccharides were isolated, and PMP-2 was subjected to structural elucidation. The results indicated that PMP-2 has a molecular weight of 124.4 kDa and that arabinose and galactose are the main components, accounting for 27.8 % and 58.5 %, respectively. Methylation and NMR analysis suggested that PMP-2 is an Arabinogalactan composed of 1,6-linked Galp and 1,4-linked Galp as the main chain, with arabinan and rhamnose as side chains. Furthermore, PMP-C and PMP-2 exhibited concentration-dependent antioxidant activities against DPPH, ABTS, and hydroxyl radicals and certain immunomodulatory activities related to the release of NO, TNF-α and IL-6. These findings suggest that PMP-2 has potential therapeutically active ingredient in functional foods. The developed method successfully removed starch and isolated non-glucan polysaccharides from the high-starch content plant P. mirifica and can be applied to other high-starch plants.
野葛（Pueraria mirifica）的干根是一种在亚洲国家广泛食用的食品。野葛以其高淀粉含量而闻名。由于淀粉的干扰，从高淀粉植物部分分离多糖是具有挑战性的。因此，本研究旨在开发一种从野葛（PMP）中分离和研究非葡聚糖多糖的结构和活性的技术。使用α-淀粉酶水解和彻底的膜透析开发了一种有效的淀粉去除工艺。分离得到了四种非葡聚糖多糖，并对 PMP-2 进行了结构阐明。结果表明，PMP-2 的分子量为 124.4 kDa，阿拉伯糖和半乳糖是主要成分，分别占 27.8%和 58.5%。甲基化和 NMR 分析表明，PMP-2 是一种阿拉伯半乳聚糖，由 1,6-连接的 Galp 和 1,4-连接的 Galp 作为主链组成，阿拉伯聚糖和鼠李糖作为侧链。此外，PMP-C 和 PMP-2 对 DPPH、ABTS 和羟基自由基表现出浓度依赖性的抗氧化活性，并对 NO、TNF-α 和 IL-6 的释放具有一定的免疫调节活性。这些发现表明，PMP-2 可能是功能性食品中具有治疗活性的成分。该方法成功地从高淀粉含量的植物野葛中去除了淀粉并分离出非葡聚糖多糖，可应用于其他高淀粉植物。
