“南薯88”茎叶多糖的分离纯化，结构鉴定及其生物活性的研究

Isolation，Purification，Structure Identification And Biological Activity of Polysaccharides From Stems And Leaves of "Nanshu 88"

摘要:

晒干的“南薯88”的茎叶，通过热水浸提，乙醇沉淀，DEAE－cellulose column 柱层析分离纯化，得到“南薯88”多糖纯品（N88P-1）。通过红外光谱技术（IR），高效凝胶渗透色谱（HPGPC），高效液相色谱色谱（HPLC） 和核磁共振谱（1 H NMR）等对“南薯88”多糖（N88P-1）的进行了结构鉴定；同时，对“南薯88”多糖（N88P-1）的抗氧化及免疫调控作用进行了初探。结果显示，“南薯88”多糖（N88P-1）的分子量为1 4328 D，红外光谱显示，在3 444.81 cm-1出现O-H的特征伸缩振动峰，1 640.20 m-1出现C=O的特征伸缩振动峰，1H NMR谱显示 δ 4.93~δ 4.86 出现异头氢信号，高效液相色谱色谱显示N88P-1的单糖组成为1∶1的半乳糖和甘露糖。活性研究结果显示，一定范围内的N88P-1浓度可以清除ABTS + 自由基，IC50值为0.48 mg/mL。 N88P-1在0.25~3 mg/mL的浓度范围内与DPPH - 自由基的清除能力呈正相关，IC50值为0.96 mg/mL。当N88P-1的浓度为3 mg/mL时，对ABTS + 和DPPH - 自由基的清除能力均达到最高值；免疫细胞增殖活性结果显示，N88P-1在20~80 mg/mL的浓度下，对B细胞和T细胞增殖效果为极显著（P＜0.01）；在10~40 mg/mL的浓度下，对巨噬细胞增殖效果为极显著（P＜0.01），其中，N88P-1在40 mg/mL的浓度下对3种免疫细胞的增殖效果均达到最佳。

Abstract:

The "Nanshu 88" polysaccharide（N88P-1） is obtained from the dried stems and leaves of "Nanshu 88" by hot water extraction，ethanol precipitation，and then purified by DEAE-cellulose 52 column chromatography. The structure of "Nanshu 88" pure polysaccharide（N88P-1） is identification by Infrared spectroscopy（IR），High Performance Gel Penetration Chromatography（HPGPC），High Performance Liquid Phase Chromatographic（HPLC） and nuclear magnetic resonance spectra（1H NMR and 13C NMR）. At the same time，the antioxidant and immune regulation effects of N88P-1 are also carries out. The results show that N88P-1 has molecular weight of 14 328 D. The infrared spectra shows the characteristic peaks of O-H stretching vibration appears in 3 444.81 cm-1，and the characteristic peaks of C=O stretching vibration appears in 1 640.20 cm-1. 1H NMR spectra showed anomeric hydrogen signals at δ4.93~δ4.86. High performance liquid chromatography（HPLC） chromatography shows N88P-1 is composed of galactose and mannose with the ratio of 1∶1. The activity study shows the N88P-1 has ability to clear the ABTS + free radical in a certain range of concentration，and the IC50 value is 0.48 mg/mL. The DPPH - free radical scavenging activity of N88P-1 is positively correlated with concentration in the range of 0.25~3 mg/mL，the IC50 value is 0.96 mg/mL. When the concentration of N88P-1 is 3 mg/mL，the scavenging activity of ABTS + and DPPH - free radical both reach the highest value. The proliferation activity of the immune cells results show that the proliferation effect on B cells and T cells are very significant（P<0.01） in the concentration of 20~80 mg/mL；while the effect of macrophage proliferation was very significant（P<0.01） in the concentration of 10~40 mg/mL；It is worth noting that the proliferation effect of the three kinds of immune cells all reached the highest value in the concentration of 40 mg/mL.