【摘要】 目的:解析芜菁多糖的化学结构,证明其体内抗疲劳功效。方法:采用水提醇沉法提取,经葡聚糖凝胶柱分离纯化得到芜菁多糖试样(纯度94.61%,得率0.94%,均以干基计)。用HPGPC、红外光谱、甲基化、GC-MS和NMR等分析手段对芜菁多糖的化学结构进行系统研究,采用小鼠负重游泳试验模型研究其抗疲劳功效。结果:芜菁多糖是一种富含半乳糖醛酸的酸性多糖(重均分子质量Mw为193.18 ku),糖基组成分析表明其含有7种单糖,物质的量百分比(mol,%)为半乳糖醛酸(D-GalA)∶甘露糖(D-Man)∶阿拉伯糖(L-Ara)∶半乳糖(D-Gal)∶葡萄糖(D-Glc)∶鼠李糖(L-Rha)∶葡萄糖醛酸(D-GlcA)=67.73∶17.19∶10.20∶3.19∶1.11∶0.34∶0.23;甲基化、GC-MS以及NMR等分析结果表明,β-1,3,6-GalpA与β-1,3-Galp(A)以1,3连接方式形成芜菁多糖的核心骨架。芜菁多糖在抗疲劳活性方面,与空白对照组相比,芜菁多糖[100 mg/(kg bw·d)]能显著延长小鼠负重游泳的时间(P<0.05),并提高小鼠前5 min的平均游泳速率(P<0.05);同时,显著提高小鼠血清谷胱甘肽过氧化物酶(GSH-Px)(P<0.05)的活力,降低乳酸脱氢酶(LDH)活力(P<0.01),并显著降低其代谢产物血清尿素氮(BUN)、乳酸(LA)和丙二醛(MDA)的水平(P<0.05)。结论:芜菁多糖是一种富含半乳糖醛酸的酸性多糖,是芜菁发挥抗疲劳作用的主要功效成分。更多还原

【Abstract】 In order to investigate structure features and anti-fatigue effect in vivo of Tibetan Turnip(Brassica rapa L.) polysaccharides(TP), in present study, TP with purity of 94.61%(dw, 0.94% yield of raw material) was obtained by hot water extraction-ethanol precipitation and sephacryl S-100 HR gel-filtration chromatography purification. The physicochemical properties of TP were analyzed by HPGPC, IR, methylation, GC-MS and NMR analyses. Moreover the anti-fatigue effect of TP was evaluated by weight-loaded mice swimming model. Collectively, TP was an acidic homopolysaccharide with average molecular weight(Mw) of 193.18 ku comprising of D-GalA ∶D-Man ∶ L-Ara ∶ D-Gal ∶ D-Glc ∶L-Rha ∶ D-GlcA=67.73 ∶ 17.19 ∶ 10.20 ∶ 3.19 ∶ 1.11 ∶ 0.34 ∶ 0.23(mol,%). Furthermore, the results of monosaccharide compositions, methylation, GC-MS and NMR analyses suggested that TP, comprising of β-1, 3, 6-GalpA and β-1, 3-Galp(A)which were alternatively linked by one with another forming the backbone. Compared with control, TP could effectively elongate swimming time and average swimming speed of test [100 mg/(kg bw·d), P<0.05]. And TP also enhanced glutathione peroxidase(GSH-Px) activity(P<0.05) and lowered lactate dehydrogenase(LDH) activity [100 mg/(kg bw·d),P<0.01] in the serum of mice. Meanwhile TP with the dosage of 100 mg/(kg bw·d) significantly reduced levels of blood urea nitrogen(BUN), lactic acid(LA) and malonic dialdehyde(MDA) in serum(brain) of mice(P<0.05). TP was a kind of acidic polysaccharide with high content of D-GalA, which was verified to be anti-fatigue component of Tibetan Turnip(Brassica rapa L.).更多还原