穿山龙多糖DMA的结构和抗氧化活性研究（英文）北大核心CSCD

采用热水煮提法和DEAE-琼脂糖凝胶CL-6B凝胶层析对穿山龙多糖DMA进行提取和分离纯化。通过高效液相色谱法和气相色谱法鉴定DMA的纯度和糖原组成。采用红外光谱法,高碘酸氧化-Smith降解法,甲基化分析以及核磁共振法对多糖DMA的结构进行分析。利用羟自由基实验研究DMA的抗氧化活性。研究发现多糖DMA显示一个单一对称的色谱峰,主要由葡萄糖组成,是由→6)-α-D-Glcp-(1→组成的多糖。DMA具有清除羟自由基的活性。     

穿山龙多糖DMA的结构和抗氧化活性研究（英文）

采用热水煮提法和DEAE-琼脂糖凝胶CL-6B凝胶层析对穿山龙多糖DMA进行提取和分离纯化。通过高效液相色谱法和气相色谱法鉴定DMA的纯度和糖原组成。采用红外光谱法,高碘酸氧化-Smith降解法,甲基化分析以及核磁共振法对多糖DMA的结构进行分析。利用羟自由基实验研究DMA的抗氧化活性。研究发现多糖DMA显示一个单一对称的色谱峰,主要由葡萄糖组成,是由→6)-α-D-Glcp-(1→组成的多糖。DMA具有清除羟自由基的活性。     

阳春砂多糖的分离纯化及体外抗氧化作用研究

本实验研究了阳春砂多糖(AVP)及其纯化组分的抗氧化活性,首先采用DEAE-纤维素-52离子交换柱分级洗脱阳春砂粗多糖,再采用Sephadex G-100葡聚糖凝胶色谱柱进一步纯化得到纯化多糖;分别采用超氧阴离子自由基体系、羟基自由基体系、1,1-二苯基苦基苯肼自由基体系,对阳春砂多糖的抗氧化活性进行研究,并以维生素C为阳性对照物,实验结果表明阳春砂粗多糖及纯化组分对超氧阴离子自由基、羟基自由基、1,1-二苯基苦基苯肼自由基均有较强的清除能力,AVP-3体外抗氧化活性最强。     

Enterobacter cloacae Z0206细菌胞外多糖的体外抗氧化活性研究

本实验旨在对Enterobacter cloacae Z0206菌进行发酵培养,以制备胞外多糖,并对其体外抗氧化活性进行初步研究。通过产多糖菌E.cloacaeZ0206的深层发酵制备细菌胞外多糖,在此基础上对其清除DPPH自由基、超氧阴离子、抑制羟自由基的能力以及还原力等四个方面进行实验,评价其抗氧化活性。结果表明,深层发酵制备的E.cloacaeZ0206胞外多糖产量为6.62g/L,其在5mg/mL时对DPPH自由基和羟自由基的清除率分别达到61.57%和40.08%。提示E.cloacaeZ0206细菌胞外多糖具有显著的抗氧化能力,具有开发为抗氧化类食品或药品的潜力。     

羧甲基茯苓多糖体外抗氧化活性研究

目的：比较不同浓度洗脱液洗脱得到的羧甲基茯苓多糖的抗氧化活性。方法：以茯苓为原料提取茯苓多糖,进行羧甲基取代反应,分离和纯化得到了均一性羧甲基茯苓多糖CMP-1、CMP-2、CMP-3、CMP-4,通过测定还原能力、DPPH自由基清除率、羟基自由基清除率、超氧阴离子自由基清除率比较其体外抗氧化活性。结果：羧甲基茯苓多糖均表现出与浓度正相关的体外抗氧化活性,其中CMP-4具有相对更强的体外抗氧化活性。结论：所得羧甲基茯苓多糖样品具有不同的体外抗氧化能力,随着洗脱液浓度增加,抗氧化活性增强。     

海洋来源硫酸多糖体外抗氧化活性作用的初步研究

利用不同极性的溶剂提取、分离并检测裙带菜、紫菜、羊栖菜、糙海参这四种海洋生物的多糖类抗氧化活性物质,以期筛选出具有显著体外活性的海洋来源抗氧化剂。采用过氧化值(POV)、稳定自由基(DPPH·)、多酚氧化酶(PPO)、超氧阴离子自由基(O■)四种体外筛选方法表征不同来源硫酸多糖产物的抗氧化活性。结果显示,四种硫酸多糖可显著抑制猪油的过氧化,并可清除自由基和超氧阴离子,抑制多酚氧化酶的活性,抗氧化活性呈现出一定的浓度依赖性,显示了不同程度的抗氧化作用。这四种硫酸多糖具有发展为天然高效抗氧化剂的潜力。     

富硒食用菌多糖的体外抗氧化研究

分别采用还原力、羟自由基、超氧阴离子自由基、[DPPH.]体系和卵磷脂脂质过氧化体系等几种不同的体外抗氧化模型,对超声波法提取得到的富硒食用菌多糖的抗氧化能力进行了研究。结果表明,在各种体系中,富硒食用菌多糖均表现出较高的抗氧化性,且其浓度与抗氧化活性呈一定的量效关系,在相同的多糖浓度下,体系的抗氧化活性与硒含量有关。     

红托竹荪多糖抗氧化活性的研究

本文采用DPPH自由基、羟自由基及超氧阴离子自由基体系对红托竹荪多糖的抗氧化活性进行了研究,并同Vc和BHT进行了比较.结果表明,在0.2～1.2 mg/mL质量浓度范围内,红托竹荪多糖对DPPH自由基、羟自由基、超氧阴离子自由基的半数清除率(EC50)值分别为1.468、2.580和2.330,抗氧化活性稍强于BHT,但弱于VC.     

裂蹄木层孔菌多糖的提取工艺及抗氧化活性研究

以多糖提取率为检测指标,采用水提醇沉法提取裂蹄木层孔菌多糖。正交实验考察提取温度、提取时间和料液比对多糖提取率的影响。结果显示,提取温度和料液比对多糖提取率有显著性影响,提取时间对多糖提取率无显著性影响。最佳提取工艺为提取温度80℃、提取时间2 h、料液比1∶40(g/m L)。在此条件下,多糖平均提取率为3.20%。选用终体积分数70%的乙醇沉淀多糖12 h时,多糖得率最高。体外抗氧化活性实验结果显示,裂蹄木层孔菌多糖的总抗氧化能力、清除羟自由基和超氧阴离子自由基的能力在实验范围内随着多糖质量浓度的增加而增强。裂蹄木层孔菌多糖是一种具有抗氧化功能的药用真菌多糖。     

不同提取方法对桔梗多糖体外抗氧化性的影响

本实验考查热水浸提法、超声波提取法、微波提取法和复合酶提取法在提取桔梗多糖时对其活性所产生的影响。在模拟体外抗氧化条件下,从总还原能力、清除超氧阴离子能力、清除羟自由基能力、清除DPPH·自由基能力和体外抗肝组织自发性脂质过氧化能力等五个方面,对不同方法提取的桔梗多糖的抗氧化活性进行了分析和评估。结果表明:微波法提取的桔梗多糖体外抗氧化效果最好且差异显著(P0.01)。此方法提取的桔梗多糖对羟自由基、DPPH·自由基的清除和对脂质过氧化作用的抑制均具有较强效果,其最大多糖浓度的清除率或抑制率均接近或超过50%,但对超氧阴离子自由基的清除能力相对较弱,最大清除率仅有25%。     

Effect of acetylation on antioxidant and cytoprotective activity of polysaccharides isolated from pumpkin (Cucurbita pepo, lady godiva)

Acetylation of pumpkin (Cucurbita pepo, lady godiva variety) polysaccharide using acetic anhydride with pyridines as catalyst under different conditions was conducted to obtain different degrees of acetylation on a laboratory scale. Furthermore, antioxidant activities and cytoprotective effects of pumpkin polysaccharide and its acetylated derivatives were investigated employing various established in vitro systems. Results showed that addition of pyridine as catalyst could increase the degree of substitution, whereas volume of acetic anhydride had little effect. The acetylated polysaccharides in DPPH scavenging radical activity assay, superoxide anion radical activity assay and reducing power assay exhibited higher antioxidant activity than that of unmodified polysaccharide. H₂O₂-induced oxidative damages on rat thymic lymphocyte were also prevented by pumpkin polysaccharide and its acetylated derivatives and the derivatives presented higher protective effects. On the whole, acetylated polysaccharide showed relevant antioxidant activity both in vitro and in a cell system.     

莲子多糖的结构分析及抗氧化活性

用热水浸提、乙醇沉淀、Sevag法除蛋白分离得到水溶性莲子粗多糖。经十六烷基三甲基溴化铵（CTAB）沉淀,硼酸反应以及SephadexG-150层析纯化,得到3种莲子多糖SN1、SN2、SN3。用气相色谱、红外光谱、紫外光谱分析其化学结构。结果表明：SN1主要由葡萄糖、半乳糖组成,含a—D-吡喃葡萄糖环;SN2主链为葡聚糖、并含有其他4种单糖;SN3含7种单糖,并推测是一种酸性氨基多糖或蛋白多糖。体外抗氧化活性实验表明莲子多糖具有一定的清除自由基能力,清除·O2-的能力较强。     

Chemical analysis and antioxidant activity in vitro of a β-D-glucan isolated from Dictyophora indusiata

In this study, a water-soluble polysaccharide (PPS) from Dictyophora indusiata was purified and investigated through a combination of gel chromatography (Sephadex G-200), infrared (IR) spectroscopy, and gas chromatography-mass spectrometry (GC-MS). The results indicated that PPS has a backbone of β-conformation, mainly consist of glucose (98.58%). And the antioxidant activities of PPS were investigated in vitro including reducing power, hydroxyl assay, superoxide radical assay and DPPH scavenge activity. The results showed that PPS has antioxidant activities in all these assay systems, suggesting it may be explored as a novel natural antioxidant with potential therapeutic properties in mammalian systems.     

In vitro antioxidant activities of sulfated polysaccharide fractions extracted from Corallina officinalis

Sulfated polysaccharides (F1, F2) from seaweed Corallina officinalis were isolated through anion-exchange column chromatography. Their chemical characteristics were determined by GC, HPLC, FT-IR and UV spectra. F1 and F2 contained only two monosaccharides, namely galactose and xylose. The antioxidant activities of F1, F2 and the de-sulfated polysaccharides (DF-1, DF-2) in vitro were investigated, including hydroxyl radicals scavenging effect, superoxide radical scavenging capacity, DPPH radical activity and reducing power. As expected, antioxidant assay showed that the two sulfated polysaccharide fractions (F1, F2) possessed considerable antioxidant properties and had more excellent abilities than de-sulfated polysaccharides (DF-1, DF-2).     

In vitro antioxidant and antitumor activities of polysaccharides extracted from Asparagus officinalis

Ultrasonic circulating extraction technology was applied for the polysaccharide extraction from Asparagus officinalis. The crude polysaccharides were deproteinized by Sevag method and three main polysaccharide fractions, AOP-4, AOP-6 and AOP-8 were obtained by fractional precipitation with gradient concentrations of ethanol (40%, 60% and 80%). The in vitro antitumor and antioxidant activities of the polysaccharide fractions were evaluated by MTT assay and free radical-scavenging assay, respectively. Deproteinized AOPs showed higher antioxidant and antitumor activities than crude AOP. AOP-4 with molecular weight 5.75 × 10⁴ Da showed significant function of scavenging hydroxyl radical. Three AOP fractions had significant antitumor activity against HeLa and BEL-7404 cells in a dose dependent manner. Furthermore, the inhibit activity of AOP-4 against HeLa cells was higher than those of other AOPs and the inhibition rate reached 83.96% at the concentration of 10 mg/mL. These results indicated that the AOP might be useful for developing natural safe antitumor drugs or health food.     

Physico-chemical characterization, antioxidant and anticancer activities in vitro of a novel polysaccharide from Melia toosendan Sieb. Et Zucc fruit

A novel water-soluble polysaccharide pMTPS-3, obtained from Melia toosendan Sieb. Et Zucc fruit by hot-water extraction and ethanol precipitation, was fractionated by DEAE-52 cellulose anion-exchange and Sephadex G-100 gel filtration chromatography. Its primary structural features and molecular weight were characterized by Fourier infrared spectrometry (FTIR), gel permeation chromatography (GPC) and gas chromatography (GC). And the antioxidant activities of pMTPS-3 in vitro were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, superoxide radical scavenging assay and hydroxyl radical scavenging assay. The results suggested that pMTPS-3 was a heteropolysaccharide, composed of arabinose, glucose, mannose, and galactose in the molar ratio of 17.3:28.3:41.6:12.6 with molecular weight 26 100 Da. The purified pMTPS-3 was revealed to have notable scavenging activity against DPPH radical in a concentration-dependent manner and present a moderate inhibition of superoxide radicals with an IC₅₀ (5.6 mg/ml), and potent inhibiting power for hydroxyl radical compared with crude polysaccharide. Further, it exhibited strong inhibition effect in vitro on the growth of human gastric cancer BGC-823 cells. It is strongly evidenced that pMTPS-3 purified from the crude polysaccharides of Melia toosendan Sieb. Et Zucc could be explored as a potential antioxidant and therapeutics.     

Identification of structure and antioxidant activity of a fraction of polysaccharide purified from Dioscorea nipponica Makino

A large number of polysaccharides are present in boiling-water extraction of Dioscorea nipponica Makino. A DEAE-Sepharose CL-6B column chromatography was used to isolate the major polysaccharides from D. nipponica Makino. The largest amount of fraction of polysaccharide was subjected to further purification by gel-filtration on Sephadex G-100. The purified fraction was a neutral polysaccharide and a single peak in HPLC with Sugar KS-804 column, with a molecular weight of 38,000, and comprised mainly of glucose and fructose (45:1). Analysis by Periodate oxidation–Smith degradation indicated that there were 5.9%(1→)-glycosidic linkages, 4.94% (1 → 2)-glycosidic linkages, 61.16% (1 → 4)-glycosidic linkages, and 28% (1 → 3)-glycosidic linkages. On the basis of superoxide radical assay, hydroxyl radical assay, and self-oxidation of 1,2,3-phentriol assay, its antioxidant activity was investigated. This purified fraction of polysaccharide exhibited equivalent inhibiting power for self-oxidation of 1,2,3-phentriol to Vc, a little higher scavenging activity of superoxide radical and hydroxyl radical than Vc, and should be explored as a novel potential antioxidant.     

Antioxidant activities of five polysaccharides from Inonotus obliquus

Five polysaccharides (IOP1b, IOP2a, IOP2c, IOP3a and IOP4) were isolated and purified from Inonotus obliquus by DEAE-Sepharose fast flow and SepharoseCL-6B column chromatography. Their chemical and physical characteristics were determined and antioxidant activities were investigated on the basis of hydroxyl radical assay, superoxide radical assay and ferric-reducing antioxidant power assay. The results showed that five polysaccharides exhibited antioxidant activities, and the higher content of uronic acid and proteinous substances, the stronger antioxidant activities of polysaccharides. Besides, molecular weights of polysaccharides also influence their antioxidant activities. IOP3a and IOP4 showed higher antioxidant properties than IOP1b, IOP2a and IOP2c.     

药用真菌灵芝液体培养过程中的抗氧化活性研究

灵芝Ganoderma lingzhi是一种重要的药用真菌,已被《中国药典》正式收录。本研究主要以菌丝体干重、多糖含量、多酚含量、黄酮含量、抗坏血酸（ascorbic acid,AA）含量、总抗氧化能力（total antioxidant capacity,T-AOC）、超氧化物歧化酶（superoxide dismutase,SOD）活性、羟自由基清除能力、超氧阴离子清除能力、1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除能力、2,2′-连氮-双(3-乙基苯并噻唑-6-磺酸)[2,2′-azino-bis(3- ethylbenzthiazoline-6-sulphonic acid),ABTS]自由基清除能力、铁离子还原能力（ferric reducing antioxidant power,FRAP）和亚铁离子螯合能力为测定指标,对灵芝液体培养过程中的抗氧化活性进行了评价。结果显示,该菌具有较高的抗氧化活性,体现在液体培养过程中生长代谢旺盛,可分泌大量多糖、多酚、黄酮、AA等物质和SOD等酶类,对羟自由基、超氧阴离子、DPPH自由基及ABTS自由基等的清除效果显著,且具有较强的铁离子还原能力和亚铁离子螯合作用,这也说明该菌的抗氧化活性与其自身的生长状况、次级代谢产物分泌及还原能力等密切相关。此外,一定的环境胁迫压力也可以激发该菌启动自身的抗氧化系统以保护机体免受氧化损伤。     

Chemical modification,antioxidant and α-amylase inhibitory activities of corn silk polysaccharides

Water-soluble corn silk polysaccharides (CSPS) were chemically modified to obtain their sulfated, acetylated and carboxymethylated derivatives. Chemical characterization and bioactivities of CSPS and its derivatives were comparatively investigated by chemical methods, gas chromatography, gel filtration chromatography, scanning electron microscope, infrared spectroscopy and circular dichroism spectroscopy, scavenging DPPH free radical assay, scavenging hydroxyl radical assay, ferric reducing power assay, lipid peroxidation inhibition assay and α-amylase activity inhibitory assay, respectively. Among the three derivatives, carboxylmethylated polysaccharide (C-CSPS) demonstrated higher solubility, narrower molecular weight distribution, lower intrinsic viscosity, a hyperbranched conformation, significantly higher antioxidant and α-amylase inhibitory abilities compared with the native polysaccharide and other derivatives. C-CSPS might be used as a novel nutraceutical agent for human consumption.