为明确拐枣不同部位多糖的结构及生理活性的差异，采用水提醇沉法制备了三种拐枣多糖（HDP）——全果多糖（HDPW）、籽多糖（HDPS）和果梗多糖（HDPP）。通过紫外-可见光谱、高效尺寸排阻色谱、离子色谱、傅里叶红外光谱和扫描电子显微镜对其结构进行对比，研究结果表明，三种HDP均为酸性多糖，由不同摩尔比例的岩藻糖、鼠李糖、阿拉伯糖、半乳糖、葡萄糖、甘露糖、半乳糖醛酸和葡萄糖醛酸组成，HDPW、HDPS和HDPP的分子量均有三个色谱峰，其中HDPS的中、低分子量值（45.72×104~165.75×104 u）要高于HDPW（0.34×104~12.53×104 u）和HDPP（0.51×104~21.26×104 u），红外光谱表明HDPW及HDPP含有α-糖苷键，而HDPS是一种含有β-糖苷键的多糖。HDP对DPPH自由基、ABTS自由基和α-葡萄糖苷酶的半数抑制浓度范围分别为0.015~0.043 mg/mL、0.47~1.21 mg/mL和0.13~9.99 mg/mL，当HDPW和HDPP的质量浓度在0.1 mg/mL及以上时，可显著提升胰岛素抵抗HepG2细胞（IR-HepG2）的葡萄糖消耗率，较模型组最高可提高7.66%。较HDPS而言，HDPW和HDPP结构相似且显示出了更好的抗氧化及α-葡萄糖苷酶抑制活性，更强的IR-HepG2葡萄糖摄取促进能力，研究为拐枣的综合利用提供一定的理论依据和数据支持。

In order to clarify the structure and functional activities of polysaccharides in different parts of Hovenia dulcis, three kinds of H. dulcis polysaccharides (HDP) including whole fruit polysaccharide (HDPW), seed polysaccharide (HDPS) and peduncles polysaccharide (HDPP) were prepared by water extraction and alcohol precipitation method. Their structures were analyzed by UV-Vis spectroscopy, high performance size exclusion chromatography, ion chromatography, fourier tansform infrared spectrometer and scanning electron microscopy. At the same time, the biological activities of the three polysaccharides were evaluated by DPPH, ABTS free radical scavenging model, α-glucosidase inhibition model and IR-HepG2 cell model. All of HDPW, HDPS and HDPP were acidic polysaccharides, which were composed of Fucose, rhamnose, arabinose, galactose, glucose, mannose, galacturonic acid and glucuronic acid with different molar ratios. The molecular weights of HDPW, HDPS and HDPP had three chromatographic peaks, among which the low and medium molecular weight value of HDPs (45.72×104~165.75×104 u) was higher than HDPW (0.34×104~12.53×104 u) and HDPP (0.51×104~21.26×104 u). Infrared spectra showed that HDPW and HDPP contained α-glycosidic bond, while HDPs was a β-glycosidic linked polysaccharides. The median inhibition concentration of DPPH radical, ABTS radical and α-glucosidase were 0.015~0.043 mg/mL, 0.47~1.21 mg/mL and 0.13~9.99 mg/mL, respectively. When the mass concentration of HDPW and HDPP was 0.1 mg/mL or above, the glucose consumption rate of insulin resistant HepG2 cells (IR-HepG2) was significantly increased, and the highest increase was 7.66% compared with the model group. Compared with HDPS, HDPW and HDPP were similar in structure and showed better antioxidant and α-Glucosidase inhibition activity, stronger IR-HepG2 glucose uptake promotion ability. The study provided theoretical basis and data support for the comprehensive utilization of H. dulcis.

陕西省技术创新引导专项(2022QFY09-08)；中国农业科学院农产品加工研究所创新工程（CAAS-ASTIP-2022-IFST）