South China Agricultural University, College of Food Science, Guangzhou 510642, China.
School of Chinese Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China.
Int J Biol Macromol. 2024 Mar;261(Pt 2):129760. doi: 10.1016/j.ijbiomac.2024.129760. Epub 2024 Jan 28.
The specific structure of Polygonatum kingianum Coll. et Hemsl polysaccharide (PKP) has been rarely reported. In this study, an inulin-type fructan PKP-1, was extracted and purified from Polygonatum kingianum Coll. et Hemsl, and its structural characteristics and antioxidants activity were evaluated. The molecular weights of PKP-1 was determined to be 4.802 kDa. Monosaccharide composition analysis evidenced that PKP-1 was composed of galactose, glucose and fructose in a molar ratio of 0.8 %:7.2 %:92.0 %. Glycosidic linkage and Nuclear Magnetic Resonance (NMR) analysis revealed that PKP-1 exhibited a primary sugar residue linkage of →1-β-d-Fruf-2→2,6-β-d-Fruf-1→, where β-d-Fruf-2→ acts as the side chain and links to the C-6 position of →2,6-β-d-Fruf-1→. In vitro antioxidant activity assays demonstrated that PKP-1 enhanced the mitigation of hepatic oxidative stress in HepG2 cells induced by free fatty acids. This effect was marked by increased enzymatic activities of superoxidase dismutase (SOD) and catalase (CAT), along with elevated glutathione (GSH) levels. These findings indicate that PKP-1 could be used as a potential natural antioxidant.
玉竹块根多糖（PKP）的具体结构鲜有报道。本研究从玉竹中提取并纯化得到菊糖型果聚糖 PKP-1，对其结构特征和抗氧化活性进行了评价。PKP-1 的分子量为 4.802 kDa。单糖组成分析表明，PKP-1 由半乳糖、葡萄糖和果糖组成，摩尔比为 0.8%：7.2%：92.0%。糖苷键和核磁共振（NMR）分析表明，PKP-1 具有→1-β-d-Fruf-2→2,6-β-d-Fruf-1→的主糖残基连接，其中β-d-Fruf-2→作为侧链连接到→2,6-β-d-Fruf-1→的 C-6 位。体外抗氧化活性试验表明，PKP-1 增强了游离脂肪酸诱导的 HepG2 细胞肝氧化应激的缓解作用。这一作用表现为超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的酶活增加，以及谷胱甘肽（GSH）水平升高。这些发现表明，PKP-1 可用作一种潜在的天然抗氧化剂。
