School of Chinese Materia Medica, Guangdong Pharmaceutical University, Guangzhou 510006, China.
The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510006, China.
Molecules. 2022 Jul 25;27(15):4759. doi: 10.3390/molecules27154759.
Platycodon grandiflorum is an edible and medicinal plant, and polysaccharides are one of its important components. To further improve the utilization rate of P. grandiflorum, we investigated the effects of four different extraction methods, including hot water, ultrasonic-assisted, acid-assisted, and alkali-assisted extractions, on the polysaccharides, which were named PG-H, PG-U, PG-C, and PG-A. The findings indicated that the extraction method had a significant impact on the yield, characteristics, and immunoregulatory activity. We observed that the yields decreased in the following order: PG-H, PG-U, PG-C, and PG-A. Galacturonic acid, glucose, galactose, and arabinose were the most prevalent monosaccharides in the four PGs. However, their proportions varied. In addition, the difference between the content of glucose and galacturonic acid was more significant. PG-U had the highest glucose content, whereas PG-C had the lowest. Galacturonic acid content was highest in PG-A, while the lowest in PG-U. The molecular weight decreased in the order of PG-U, PG-H, PG-C, and PG-A; the particle size was in the order of PG-U, PG-A, PG-H, and PG-C. Moreover, the extraction method had a great impact on immunoregulatory activity. The ability to stimulate the immune function of macrophages was as follows: PG-A > PG-C > PG-U > PG-H. The results indicated that PGs, with lower molecular weights and higher GalA content, exhibited better immune-stimulating activity. And more important the AAE method was a good way to extract polysaccharides from Platycodon grandiflorum for use as a functional product and immunological adjuvant.
桔梗是一种药食同源植物，多糖是其重要成分之一。为了进一步提高桔梗的利用率，我们研究了四种不同提取方法（热水浸提法、超声辅助提取法、酸辅助提取法和碱辅助提取法）对多糖的影响，分别将其命名为 PG-H、PG-U、PG-C 和 PG-A。结果表明，提取方法对产率、特性和免疫调节活性有显著影响。我们观察到产率依次降低：PG-H、PG-U、PG-C 和 PG-A。四种 PG 中最常见的单糖为半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖，但它们的比例不同。此外，葡萄糖和半乳糖醛酸的含量差异更为明显。PG-U 中葡萄糖含量最高，PG-C 中最低。PG-A 中半乳糖醛酸含量最高，PG-U 中最低。PG-U 的分子量最小，PG-C 的分子量最大；PG-U 的粒径最小，PG-C 的粒径最大。此外，提取方法对免疫调节活性有很大影响。刺激巨噬细胞免疫功能的能力如下：PG-A>PG-C>PG-U>PG-H。结果表明，分子量较低、GalA 含量较高的 PG 具有更好的免疫刺激活性。更重要的是，AAE 法是从桔梗中提取多糖作为功能性产品和免疫佐剂的一种很好的方法。
