勃氏甜龙竹笋壳多糖提取工艺优化、结构表征及体外生物活性分析

刘靖洁; 彭小伟; 王安娜; 夏文茜; 曹昌伟; 阚欢; 刘云

doi:10.13386/j.issn1002-0306.2024070363

勃氏甜龙竹笋壳多糖提取工艺优化、结构表征及体外生物活性分析

Optimization of Extraction Process, Structural Characterization and In Vitro Bioactivity of Polysaccharides from Dendrocalamus brandisii Bamboo Shoot Shell

摘要

摘要: 通过Box-Behnken响应面法优化勃氏甜龙竹笋壳多糖（Polysaccharides from Dendrocalamus brandisii bamboo shoot shell，PDB）的提取工艺，综合运用高效凝胶渗透色谱法、离子色谱法、紫外光谱、傅里叶红外光谱、扫描电镜、刚果红实验对经DEAE-52纤维素柱分离的PDB进行结构表征，并评价各组分的体外抗氧化、降血糖、降血脂活性。结果表明，当碳酸钠浓度为4.1 mg/mL、超声功率310 W、超声时间81 min、超声温度66 °C时，PDB的得率最高，为2.09%；PDB经DEAE-52纤维素柱分离后得到三个组分PDB-0、PDB-1和PDB-2，均主要由阿拉伯糖、半乳糖、葡萄糖和木糖组成，红外光谱发现三个组分具有典型的多糖特征峰。体外生物活性实验发现三个多糖组分均表现出一定的抗氧化、降血糖和降血脂活性，其中PDB-2抗氧化活性最为突出，清除DPPH·、ABTS⁺·的半抑制浓度（IC₅₀）分别0.74±0.05 mg/mL和0.64±0.01 mg/mL，当浓度为1 mg/mL时，铁还原实验吸光度值为0.331；各组分抑制α-淀粉酶活性的IC₅₀值分别为0.78±0.05、0.82±0.04和0.94±0.02 mg/mL；在浓度达到1 mg/mL时，PDB-0、PDB-1和PDB-2结合胆酸钠、牛黄胆酸钠、甘氨胆酸钠的比率分别达到17.66%±0.12%、21.06%±0.45%和22.28%±0.51%，24.79%±0.79%、26.27%±0.78%和32.57%±0.75%，22.46%±0.79%，25.52%±0.23%和23.16%±0.78%。综上所述，PDB具有良好的体外抗氧化、降血糖和降血脂活性，在食品抗氧化剂和保健品的研发中具有较大潜力。

Abstract: The extraction process of polysaccharides from Dendrocalamus brandisii bamboo shoot shell (PDB) was optimized by Box-Behnken response surface method, and high performance gel permeation chromatography, ion chromatography, ultraviolet spectroscopy, and Fourier infrared spectroscopy were comprehensively applied, Scanning electron microscopy, and Congo red assay were used to characterize the structure of PDB separated by DEAE-52 cellulose column, and to evaluate the in vitro antioxidant, hypoglycemic, and hypolipidemic activities of each component. The results showed that the highest extraction rate of PDB was 2.09% when the concentration of sodium carbonate was 4.1 mg/mL, the ultrasonic power was 310 W, the ultrasonic time was 81 min, and the ultrasonic temperature was 66 °C. PDB was separated by a DEAE-52 cellulose column to obtain the three fractions, namely PDB-0, PDB-1, and PDB-2, which were all mainly composed of arabinose, galactose, Glucose and Xylose, and the IR spectra showed that the three fractions had typical polysaccharide characteristic peaks. In vitro bioactivity experiments revealed that all three polysaccharide fractions exhibited certain antioxidant, hypoglycemic and hypolipidemic activities, among which the antioxidant activity of PDB-2 was the most prominent, with the half-inhibitory concentrations (IC₅₀) of 0.74±0.05 mg/mL and 0.64±0.01 mg/mL, respectively, for the removal of DPPH· and ABTS⁺·. When the concentration was 1 mg/mL, the absorbance value of the iron reduction assay was 0.331; the IC50 values for the inhibition of α-amylase activity by each component were 0.78±0.05, 0.82±0.04 and 0.94±0.02 mg/mL, respectively, at concentrations of 1 mg/mL, the binding ratios of PDB-0, PDB-1 and PDB-2 to sodium cholate, sodium taurocholate, and sodium glycylcholate were respectively up to 17.66%±0.12%, 21.06%±0.45%, and 22.28%±0.51%; 24.79%±0.79%, 26.27%±0.78%, and 32.57%±0.75%; 22.46%±0.79%, 25.52%±0.23% and 23.16%±0.78%. In summary, PDB has good in vitro antioxidant, hypoglycemic and hypolipidemic activities and has great potential in the development of food antioxidants and nutraceuticals.