不同来源多花黄精多糖的结构特性及抗氧化活性比较

Structural Characteristics and Antioxidant Activities of Polygonatum cyrtonema Hua Polysaccharides with Different Origins

摘要:

以5种不同来源多花黄精为原料，通过水提醇沉法制备黄精多糖，利用离子色谱、高效凝胶渗透色谱、傅里叶红外变换光谱、X-射线衍射仪和扫描电镜等技术研究其结构性质，并评价其抗氧化活性。结果表明，5种多花黄精的多糖含量在7.63%~16.78%质量分数范围内，相互间有显著性差异（P<0.05），且产自江西铜鼓的黄精多糖含量最高（16.78%）；5种多花黄精多糖均为杂多糖，单糖组成以果糖为主。红外光谱表明5种多花黄精多糖均具有典型糖类吸收峰，含有α-糖苷键和β-糖苷键；其微观形貌主要呈不规则片状或多孔片状结构。抗氧化活性实验显示，5种多花黄精多糖具有一定抗氧化能力，在2~10 mg/mL的浓度范围内对1,1-二苯基-2-苦基肼自由基和羟自由基清除能力呈一定的剂量依赖性，其中江西铜鼓多花黄精多糖的抗氧化活性最好。该研究反映了不同来源多花黄精多糖的结构特性和自由基清除能力差异，可为多花黄精的良种选育和资源利用提供科学依据。

Abstract:

The “water extraction and alcohol precipitation” method was utilized to prepare Polygonatum cyrtonema polysaccharides (PCPs) derived from Polygonatum cyrtonema Hua (PCH) plants grown in five different areas. Comprehensive characterization of the structural features of each PCP was conducted using ion chromatography, high-performance gel-permeation chromatography (HP-GPC), Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), and scanning electron microscopy (SEM). Additionally, the antioxidant activity of each PCP was evaluated. The analyses revealed that the PCP contents varied among the five PCHs, ranging from 7.63% to 16.78%, with statistically significant differences observed in PCP content between the PCHs (P<0.05). Notably, the PCH sourced from Tonggu County (Jiangxi Province) exhibited the highest PCP content (16.78%). All PCPs identified in the study were heteropolysaccharides, with fructose dominating their monosaccharide composition. FTIR spectra of all PCPs displayed characteristic carbohydrate absorption peaks, indicative of α- and β-glycosidic bonds. The micromorphology of PCPs exhibited irregular or porous sheet-like structures. The antioxidant activity assays demonstrated that all five PCPs exhibited varying degrees of antioxidant activity. In the concentration range of 2~10 mg/mL, they exhibited dose-dependent scavenging activities for DPPH and hydroxyl radicals, with the PCP derived from Tonggu County demonstrated the highest antioxidant activity. By revealing the distinct structural characteristics and radical scavenging activities of PCPs from different origins, this study provides a scientific foundation for the breeding and utilization of PCH.