海带低分子量岩藻聚糖硫酸酯的制备和抗血小板聚集活性研究

目的：研究低分子量海带岩藻聚糖硫酸酯的制备和纯化技术,筛选抗血小板聚集活性的低分子量海带岩藻聚糖硫酸酯。方法：以海带硫酸多糖为原料,采用自由基降解和强阴离子交换色谱技术,制备纯化出高硫酸根和高岩藻糖的低分子量岩藻聚糖硫酸酯;采用体外凝血酶诱导血小板聚集模型,筛选出抗血小板聚集活性的低分子量岩藻聚糖硫酸酯。结果：强阴离子交换色谱能够有效地将复杂的低分子量海带岩藻聚糖硫酸酯分离纯化,得到4个纯度较高的高硫酸根、高岩藻糖的低分子量多糖,其岩藻糖含量超过85% ~ 95%,硫酸根含量35%以上,分子量在20 ku ~ 30 ku。体外抗血小板聚集试验结果证明,这4个高硫酸根高岩藻糖组分的抗血小板聚集活性最高,而低硫酸根组分含有较高的半乳糖、甘露糖和糖醛酸,其抗血小板活性非常低。结论：采用自由基氧化降解和强阴离子交换色谱法,可获得抗血小板活性高的高硫酸根高岩藻糖的低分子量岩藻聚糖硫酸酯。     

硫酸化多糖抗肿瘤研究进展

摘 要硫酸化多糖是糖羟基上含有硫酸根的多糖,可经天然提取或硫酸化的化学修饰而得到。近年的研究证明硫酸化多糖呈现了不同程度的抗肿瘤活性,尤其是与化学修饰前相比其抗肿瘤活性显著增强,引起广泛的关注。本文对近几年国内外与天然硫酸化多糖和化学合成硫酸化多糖抗肿瘤活性相关的研究进行综述。     

小有刺参硫酸软骨素和岩藻聚糖硫酸酯抗血小板聚集活性的比较

目的 从小有刺参中制备纯化硫酸软骨素和岩藻聚糖硫酸酯及其低分子量组分,并比较不同结构硫酸多糖的抗血小板聚集活性,揭示海参硫酸多糖抗血小板聚集活性的构效关系。方法 利用离子交换色谱和自由基降解技术,从小有刺参中制备硫酸软骨素和岩藻聚糖硫酸酯及各自的低分子量组分。采用体外凝血酶诱导血小板聚集模型,比较不同结构的硫酸软骨素和岩藻聚糖硫酸酯对血小板聚集率的影响。结果 4～60 μg/mL硫酸软骨素和低分子量硫酸软骨素具有显著的抑制血小板聚集的活性,在浓度为20 μg/mL时对血小板聚集的抑制率高达94.6%和95.3%,且分子量的降低对其活性无影响。比较不同来源的岩藻聚糖硫酸酯的活性发现,在4～60 μg/mL浓度范围内,海参与海带来源的岩藻聚糖硫酸酯都显著抑制血小板聚集,且活性没有显著差异,但经过自由基降解后,海参和海带来源的岩藻聚糖硫酸酯的抗血小板聚集活性都显著降低。结论 海参硫酸软骨素的抗血小板聚集活性显著高于岩藻聚糖硫酸酯,海参硫酸多糖可以应用于新型抗血小板聚集药物的研究开发。     

昆布多糖硫酸酯的制备及抗肿瘤活性研究

目的对昆布多糖进行硫酸酯化修饰,考察修饰前后多糖结构及抗肿瘤活性的变化。方法采用氯磺酸-吡啶法进行多糖硫酸酯化修饰,高效液相色谱测定分子量,红外光谱检测官能团,扫描电镜观察表面形态,采用MTT法进行抗肿瘤活性评价。结果昆布多糖硫酸酯化修饰后,硫酸基含量为37.8%,昆布多糖硫酸酯的分子量为13 000,红外光谱出现硫酸基的特征吸收峰。昆布多糖及其硫酸酯表面立体形态差异显著,昆布多糖呈云雾状或海绵状,昆布多糖硫酸酯呈枝状、片状和球状颗粒的形式。昆布多糖及其硫酸酯对人结肠癌细胞LOVO生长都具有明显的抑制作用,并且昆布多糖硫酸酯的抗肿瘤活性强于昆布多糖。结论对多糖进行一定程度的硫酸酯化修饰,可以改变多糖的理化性状、增强生物活性。     

硫酸化香菇多糖的琼脂糖电泳鉴别

目的用琼脂糖凝胶电泳鉴别香菇多糖及硫酸化香菇多糖。方法利用肝素、低分子肝素、香菇多糖、硫酸化香菇多糖之间电荷密度及相对分子质量的差异 ,在巴比妥缓冲液中进行琼脂糖凝胶电泳。结果根据电泳迁移率的不同 ,可明显区分香菇多糖及其硫酸化衍生物。结论该法重现性好 ,操作简单 ,可用于香菇多糖及硫酸化香菇多糖的鉴别。     

双多糖多相脂质体的研究——1.多糖中有效成分的选择和鉴定

用乙醇分级沉淀的方法将人参多糖和黄芪多糖分级、精制。研究了不同组分的纯度、分子量分布和单糖组成,并对其抗肿瘤作用进行了初步比较,为选择加入脂质体制剂中的多糖组分做了必要的实验准备。     

化学修饰硫酸酯化多糖抗HIV活性研究进展

对近年来化学修饰硫酸酯化多糖的制备,构效关系及其抗HIV病毒活性的研究进行综述。用化学方法对多种来源的天然多糖进行不同程度的硫酸酯化或去硫酸酯化,研究主链结构、支链、分子量、硫酸基取代度、硫酸基取代位置对化学修饰硫酸酯化多糖体内外抗HIV活性的影响,以及硫酸酯化多糖抗HIV活性的作用机理。     

NaHSO3/NaNO2法修饰海带多糖及抗肿瘤活性研究

目的:对海带多糖进行硫酸酯化修饰,考察修饰前后多糖结构及抗肿瘤活性的变化.方法:采用三磺酸钠胺水相法对海带多糖进行硫酸化修饰,对反应条件进行单因素分析,红外光谱核磁共振谱分析海带多糖以及硫酸酯结构,BaSO4-明胶分光光度法测定产物硫酸基,采用苯酚-浓硫酸法测定海带及其硫酸酯多糖含量,高效液相色谱法测定分子量,MTT法进行抗肿瘤活性评价.结果:海带多糖硫酸酯化后,硫酸根含量为38.34％,多糖含量为55.65％.海带多糖及硫酸酯的分子量分别为5000和14,000.硫酸基在红外光谱出现特征吸收峰.海带多糖是β-吡喃型葡萄糖以1,3-糖苷键为主链,海带多糖硫酸酯的硫酸基团取代位置为C2-OH.海带多糖及其硫酸酯对人乳腺癌MCF-7细胞、人结肠癌细胞LOVO增殖的抑制作用.结论:海带多糖经过硫酸化修饰后,其对抗肿瘤细胞的作用高于未经修饰的海带多糖,且海带多糖硫酸酯对LOVO细胞的敏感性优于对MCF-7细胞.     

香菇多糖的抗肿瘤活性研究

目的:研究香菇多糖(EGb)的体内、体外抗肿瘤活性。方法:选取人乳腺癌细胞MCF-7、肝癌细胞HepG2、胃癌细胞SW480,不同浓度的香菇多糖分别处理3种肿瘤细胞,MTT法分别检测香菇多糖的体外抗肿瘤活性;选取荷MCF-7肿瘤裸鼠,给予香菇多糖,通过肿瘤生长抑制率,考察香菇多糖的体内抗肿瘤活性。结果:香菇多糖对3种肿瘤细胞均有细胞毒性,呈剂量依赖性,IC50分别为6.855、10.083、8.563μM;香菇多糖可显著降低肿瘤重量,提高肿瘤生长抑制率。结论:香菇多糖体内外实验均显示良好抗肿瘤活性。     

山豆根多糖硫酸化修饰及其体外抗HBV活性测定

目的对山豆根多糖进行硫酸化修饰并对其抗HBV活性进行测定。方法提取山豆根多糖,采用氯磺酸-吡啶法对山豆根多糖进行硫酸化修饰,产物经红外光谱鉴定。用MTF法测定该修饰物的抗HBV活性。结果通过山豆根多糖硫酸化前后的红外图谱分析,表明硫酸基与多糖已结合成酯,并且有抗HBV的作用。结论山豆根多糖硫酸化修饰能提高对乙型肝炎病毒细胞转染的2215细胞培养液中HBeAg、HBsAg的抑制作用。     

低分子螺旋藻多糖的制备及其硫酸酯化物体外抗肿瘤活性的初步研究

运用盐酸控制解聚的方法,通过单因素考察和正交试验优化,得到了平均相对分子质量约为10 000的低分子螺旋藻多糖（LNPSP）,用硫酸化试剂氯磺酸-吡啶合成3种不同取代度的LNPSP硫酸酯（SLNPSP1,SLNPSP2,SLNPSP3）,采用体外抗肿瘤实验测定3种硫酸酯化物对人肝癌细胞SMMC7721的活性.结果显示：低分子螺旋藻多糖的硫酸酯化物具有良好的体外抗肿瘤活性,与未修饰的LNPSP相比有显著性差异,且随着硫酸化程度的增高抗肿瘤活性也相应提高.     

香菇多糖对肿瘤微环境免疫调节作用的研究进展

香菇是药食两用的真菌,香菇多糖是其中的活性代表成分。近年来,香菇多糖在免疫功能调节方面的作用成为研究的热点。研究证实香菇多糖通过刺激机体的免疫器官、促进淋巴细胞的增殖分化、增加NK细胞活性、在基因和分子层次上促进免疫功能的表达,以恢复机体的免疫功能和肿瘤微环境中的免疫平衡,这些因素在抗肿瘤的治疗中体现出巨大的价值。旨在将香菇多糖对肿瘤免疫微环境中的影响及香菇多糖在基因层次调控免疫功能的国内外最近研究进展进行综述,为其在抗肿瘤治疗及其他领域的综合开发提供参考。     

特定分子量范围内香菇多糖的分离研究

目的:研究平均分子量为400000～600000范围内香菇多糖的分离工艺。方法:将精制的香菇多糖进行2—二乙氨基乙基—纤维素阴离子交换柱色谱纯化,再通过葡聚糖凝胶G-200柱层析法进行分离;以高效凝胶色谱法测定香菇多糖的分子量。结果:分离得到的香菇多糖平均分子量为400000～600000。结论:本方法可用于香菇多糖的分离。     

聚乙二醇化重组人肿瘤坏死因子-α:制备和抗肿瘤活性

AIM: To assess the merits of polyethylene glycol-modified recombinant human tumor necrosis factor alpha (PEG-rHuTNF-alpha). METHODS: The rHuTNF-alpha was modified with N-succinimidyl succinate monomethoxy polyethylene glycol (SS-PEG) of three different molecular weights. The PEG-rHuTNF-alpha was separated into fractions of various molecular weights by gel filtration chromatography. In vitro activities of various fractions were determined with L929 cell assay and in vivo anti-tumor potencies of main fractions were studied with respect to necrosis of S-180 solid tumor. RESULTS: The rHuTNF-alpha could be modified using SS-PEG under mild conditions. The main fraction of PEG5000-rHuTNF-alpha contained four PEG molecules, and PEG12000-rHuTNF-alpha and PEG20000-rHuTNF-alpha contained two PEG molecules, respectively. There was a higher activity when rHuTNF-alpha was coupled to less numbers of the same molecular weight PEG molecules. When PEG-rHuTNF-alpha was of the same molecular weight, rHuTNF-alpha modified with bigger molecular weight PEG molecules had a higher activity. PEG-rHuTNF-alpha was resistant to proteolysis, and over 70 % activity remained after 8 h, but the activity of rHuTNF-alpha was time-dependently diminished by incubation with bovine trypsin. PEG5000-rHuTNF-alpha (1500 IU per mouse) had a similar anti-tumor potency compared with rHuTNF-alpha (3000 IU per mouse). PEG12000-rHuT NF-alpha (1500 IU per mouse) had an increased anti-tumor potency compared with rHuTNF-alpha (3000 IU per mouse). In particular, PEG20000-rHuTNF-alpha at a dose of 1500 IU per mouse had a higher anti-tumor potency than rHuTNF-alpha at a dose of 6000 IU per mouse. CONCLUSION: PEG-modified rHuTNF-alpha could be more suitable for therapeutic use     

凝胶色谱法同时测定香菇多糖制剂中多糖分子量和含量

目的 建立一种同时测定香菇多糖制剂中多糖分子量分布和含量的凝胶色谱方法.方法 采用TSKgel G5000PWxl、G4000PWxl、G3000PWxl （7.8 mm×30 cm,7μm）凝胶色谱柱串联,以右旋糖苷为对照品,0.1 mol· L-1乙酸钠-乙酸水溶液为流动相,通过示差检测器检测,柱温为60℃,流速为0.6 mL·min-1,进样量为100 μ上L.结果 Dextrans的分子量对数logM/W与峰保留时间在22～47 min内呈良好的线性关系（r=0.9990）;多糖进样量在20.12～201.20 μg范围内与峰面积呈良好的线性关系（r =0.9999）,加样回收率平均值为106.33％,RSD=1.55％（n=9）.结论 本方法简便、准确、重复性好,可用于香菇多糖注射制剂的质量控制.     

超声波辅助过氧化氢氧化降解制备相对低分子质量异枝麒麟菜硫酸多糖

目的 制备相对低分子质量异枝麒辟菜硫酸多糖。方法 采用超声波辅助过氧化氢氧化降解异枝麒辟菜硫酸多糖，并测定各多糖样品的相对分子质量及硫酸基、3，6-内醚半乳糖含量。结果 制备了相对分子质量为5000～40000的硫酸多糖，其硫酸基含量均在18．5％以上。结论 该方法适合于制备相对低分子质量高水溶性多糖，后处理简单，并能较好地保持多糖中的硫酸基。     

In vivo growth-inhibition of S180 tumor by mixture of 5-Fu and low molecular lambda-carrageenan from Chondrus ocellatus.

Lambda-carrageenan is a sulfated galactan isolated from some red algae and have been reported to have many kinds of biological activities. Chondrus ocellatus is an important economic alga in China and many other parts of the world. The sample was obtained after lambda-carrageenan from the alga was degraded by microwave and its molecular weight is 9.3 kDa. In this study, tumor inhibiting activity of low molecular weight lambda-carrageenan and its mixture with 5-Fu on mice transplanted with S180 tumor was investigated. Weight of immune organ, proliferation ratio of lymphocyte concentration of TNF-alpha and histopathology of spleen and tumor from the transplanted S180 tumor mice were also determined. Results indicated that the degraded lambda-carrageenan could enhance antitumor activity of 5-Fu and improve immunocompetence damaged by 5-Fu.     

Anti-tumor and immunomodulating activities of proteoglycans from mycelium of Phellinus nigricans and culture medium

Two proteoglycans, PNW1 and PNM1, were isolated from the mycelium of Phellinus nigricans through submerged fermentation and culture medium, respectively. PNW1 and PNM1 with similar average molecular weight (33 kDa and 29 kDa) were composed of glucose, galactose, mannose, arabinose and fucose in the molar ratios of 3.26:8.77:6.44:1:1.35 and 20.06:8.72:6.94:1:0.76. At the dose of 100, 200, and 400 mg/kg, PNW1 and PNM1 exhibited anti-tumor activity against mice-transplanted Sarcoma 180 in vivo. However, no direct cytotoxic activity against Sarcoma 180 could be determined. Significant increase in the relative spleen and thymus weight and expression of tumor necrosis factor-alpha (TNF-alpha) in serum was observed, decreasing the tumor weight significantly. PNW1 and PNM1 could stimulate lymphocytes proliferation and increase production of nitric oxide (NO) and TNF-alpha in macrophages. The results indicate that both lymphocyte and macrophages were activated by preparations of proteoglycans from mycelium and culture medium of P. nigricans. The anti-tumor effect of the proteoglycans is not directly tumoricidal but rather immunostimulating.     

In vivo antitumor and immunomodulation activities of different molecular weight lambda-carrageenans from Chondrus ocellatus.

lambda-Carrageenan is a sulfated galactan isolated from some red algae and have been reported to have many kinds of biological activities. lambda-Carrageenan from Chondrus ocellatus, an important economic alga in China and many other parts of the world, was degraded by microwave, and obtained five products that have different molecular weight: 650, 240, 140, 15, 9.3 kDa. Analytical results confirmed that microwave degradation might not change the chemical components and structure of polysaccharides under certain condition. In this study, tumor-inhibiting activities, weight of immune organ, nature killer cells activity, lymphocyte proliferation ratio and pathological slice of spleen and tumor cells from the control group and lambda-carrageenan-treated mice of transplanted S180 and H22 tumor were investigated. The results indicated that the five lambda-carrageenan samples all showed antitumor and immunomodulation activities in different degree. Molecular weight of polysaccharides had notable effect on the activities. In addition, their antitumor and immunomodulation have some relevance and the five lambda-carrageenans probably inhibited tumor by means of activating the immunocompetence of the body. Among all the experiment results, samples with the highest activities are PC4 and PC5 whose molecular weight are 15 and 9.3 kDa.