Anticoagulant, Antioxidant and Antitumor Activities of Heterofucans from the Seaweed Dictyopteris delicatula

In the present study, six families of sulfated polysaccharides were obtained from seaweed Dictyopteris delicatula by proteolytic digestion, followed by acetone fractionation and molecular sieving on Sephadex G-100. Chemical analyses demonstrated that all polysaccharides contain heterofucans composed mainly of fucose, xylose, glucose, galactose, uronic acid, and sulfate. The fucans F0.5v and F0.7v at 1.0 mg/mL showed high ferric chelating activity (～45%), whereas fucans F1.3v (0.5 mg/mL) showed considerable reducing power, about 53.2% of the activity of vitamin C. The fucan F1.5v presented the most prominent anticoagulant activity. The best antiproliferative activity was found with fucans F1.3v and F0.7v. However, F1.3v activity was much higher than F0.7v inhibiting almost 100% of HeLa cell proliferation. These fucans have been selected for further studies on structural characterization as well as in vivo experiments, which are already in progress.     

Sulfation of silk fibroin by sulfuric acid and anticoagulant activity

Silk fibroin (Bombyx mori) was sulfated with an aqueous sulfuric acid solution. The sulfated fibroin was characterized by Fourier transform infrared spectroscopy (FTIR), amino acid analysis, and gel filtration chromatography (GFC). Maximum yield was obtained at around 2–4 h, and it decreased at 6 h and more. The molecular size decreased and dispersed with sulfation, and the molecular weight was estimated at around 10,000 by GFC using protein standards. The amino acid composition indicated that the crystal region of the fibroin molecule remained in sulfated fibroin until a sulfation reaction time of 4 h. The incorporation of sulfate groups was confirmed by FTIR and the amount of sulfate groups introduced for 4 h sulfation was estimated in 0.3 mmol/g by acidimetric titration. The efficiency of sulfation was calculated at 15.7%. Blood coagulation was prevented by 20 mg of sulfated fibroin in 1 mL of blood, while original fibroin did not show the effect. This result indicates that sulfate group introduction results in addition of anticoagulant function to silk fibroin. Although a variety of polymer backbones have been used for synthesis of sulfated polymers as anticoagulant materials, no reports are available concerning a sulfated polymer based on a protein backbone. Sulfated fibroin is a new type of anticoagulant material having a protein backbone. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2377–2382, 2003     

Chitosan and marine phospholipids reduce matrix metalloproteinase activity in myeloma SP2 tumor‐bearing mice

An animal experiment was conducted to assess the antitumor effects of chitosan‐coated liposomes on myeloma SP2. The animal experimental groups designed for myeloma SP2 tumor‐bearing BALB/c mice were provided with five different drinks: (I) control (double‐distilled water); (II) squid phospholipid liposomes alone 1.0 mg/mL; (III) chitosan alone 5.0 mg/mL; (IV) squid phospholipid liposomes 1.0 mg/mL with chitosan 5.0 mg/mL in the form of a simple mixture; and (V) squid phospholipid liposomes 1.0 mg/mL coated with chitosan 5.0 mg/mL. At 20 days after implantation of the myeloma SP2 cells into mice, oral administration of the experimental drinks was provided for 35 days. There was significant suppression of tumor growth when chitosan and squid phospholipids were administered simultaneously in a simple mixture or as chitosan‐coated liposomes. Matrix metalloproteinase (MMP)‐2 and MMP‐9 activity was significantly less in the serum of mice that consumed chitosan‐coated liposomes than in control mice. We found that decreased tumor burden was related to MMP secretion. Therefore, chitosan‐coated marine phospholipid liposomes might be useful as potential agents for the treatment of myeloma SP2.     

Isolation,physicochemical properties,and in vitro antioxidant activity of polysaccharides extracted from different parts of Pinus koraiensis

The isolation and purification of polysaccharides extracted from the cones, bark, and needles of Pinus koraiensis (Korean pine) were studied. The amounts of polysaccharides were 42.7%, 53.4%, and 48.4% for cones, bark, and needles, respectively. All these samples contained uronic acid. The total protein and polyphenols were <4.5% for all three samples. With acid hydrolysis, seven polysaccharides were found in different molar ratios in each sample: D-ribose, L-rhamnose, L-arabinose, D-xylose, D-mannose, D-glucose, and D-galactose. The relationships between in vitro antioxidant properties (AOP) of polysaccharides extracted from different parts of the P. koraiensis tree are correlated with physicochemical properties (the amount of neutral sugars, uronic acid, and proteins). Moreover, the pinecone polysaccharides (PKCP) confirmed previously observed beneficial antioxidant capacity with an EC₅₀ of OH radical, ABTS radical scavenging, and reducing power of 6.54, 5.06, and 9.15 mg/mL, respectively. PKCP had the best antioxidant activity among the three samples.     

冬凌草硒多糖的制备、表征及抗氧化活性分析

本研究以济源冬凌草多糖为原料，选用化学合成方法对多糖进行结构修饰。采用UV、FT-IR、SEM、TGA、HPLC等方法对冬凌草多糖以及硒多糖结构特征进行了表征；通过DPPH（1,1-二苯基-2-三硝基苯肼）自由基法、羟自由基法等4种方法对其抗氧化活性进行了探究。结果：制备的硒多糖中硒质量分数为1.35 mg/g。硒化修饰后，冬凌草多糖的基本骨架得到保留，单糖种类未发生改变，但其分解温度降低、稳定性下降，多糖形貌也发生明显变化，球状与条状形貌增多，片状形貌减少。此外，在体外抗氧化性实验中，当硒多糖质量浓度为1.6mg/mL时，对DPPH自由基、ABTS自由基、羟自由基清除率分别为68.68%、86.69%、45.12%，均强于冬凌草多糖。     

大孔吸附树脂对葛根总黄酮吸附性能的研究

测定分析了AB-8等6种不同极性大孔吸附树脂对葛根总黄酮的吸附特性。静态实验结果表明,树脂的极性和空间结构是影响吸附效果的重要因素。AB-8树脂孔径适当,比表面积较高,葛根黄酮吸附量达74.3 mg/g。进行了静态吸附动力学的研究,并获得总黄酮吸附量与吸附时间之间的定量关系。动态吸附研究表明,在温度为20℃时,以吸附流速4 mL/min和洗脱流速3 mL/min较合适。而重复使用约10次以后,该树脂应进行再生。     

Synthesis,characterization, and anticoagulant activity of carboxymethyl starch sulfates

To develop a renewable and compatible anticoagulant as potential heparin alternative, carboxymethyl starch sulfate (CMSS) was prepared by the reaction of carboxymethyl starch (CMS) and sulfating reagent [N(SO₃Na)₃]. The chemical structures of CMS and CMSS were characterized by Fourier transform infrared spectroscopy and ¹³C nuclear magnetic resonance. The influences of reaction parameters, including the pH of sulfating reagent, the molar ratio of sulfating reagent to CMS, reaction time, and temperature on the degree of substitution of sulfate groups (DS) of CMSS were studied. Meantime, the DS of each CMSS was determined by barium sulfate–glutin nephelometery method. Moreover, the anticoagulant activity of CMSS was investigated by the coagulation assays of activated partial thromboplastin time, thrombin time, and prothrombin time. The results revealed that the anticoagulant activity of CMSS was closely related to the DS value and concentration. The anticoagulant activity was promoted with the increasing of the DS and concentration. The molecular weight (M_w) in measured range had little impact on anticoagulant activity in contract to the DS and concentration. In this article, the CMSS with the DS of 1.91, concentration of 75 μg/mL and the M_w of 2.61 × 10⁴ had the best blood anticoagulant activities. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

海星多糖的提取分离与抗氧化活性研究

目的:从南海海星中提取多糖并研究其抗氧化活性。方法:采用碱提-酶解法提取海星多糖,并采用离子交换层析与凝胶过滤层析法进行纯化;采用醋酸纤维素薄膜电泳及凝胶过滤色谱法鉴定纯度;采用Fenton反应体系研究清除羟基自由基活性,采用邻苯三酚自氧化法研究清除超氧阴离子活性;采用H2O2损伤家兔红细胞模型研究其对生物膜的抗氧化保护作用。结果:海星多糖及阳性对照甘露醇、苯甲酸清除羟基自由基的半数有效浓度EC50分别为5.51 mg/mL、16.33 mg/mL、4.29 mg/mL;海星多糖及阳性对照维生素C清除超氧阴离子自由基的半数抑制浓度IC50分别为32.36μg/mL、18.32μg/mL;海星多糖对H2O2致红细胞损伤有良好的保护作用。结论:海星多糖具有较强的抗氧化活性。     

Insect-Induced Synthesis of Phytoecdysteroids in Spinach, Spinacia oleracea

Spinach (Spinacia oleracea) foliage is known to synthesize and accumulate insect molting hormones, predominantly in the form of 20-hydroxyecdysone (20E). We previously demonstrated that root 20E accumulation is increased following root damage. We designed two further experiments to address root responses to both mechanical and insect damage. In plants grown hydroponically, removal of 35% or less of the root mass did not result in changes in root 20E levels. However, removal of 70% of the root mass stimulated 6.0- and 1.5-fold increases in the root and shoot 20E concentrations, respectively. The effects of insect damage on soil-grown plants were investigated by infesting plant roots with black vine weevil (BVW: Otiorhynchus sulcatus) larvae and allowing them to feed for seven days. Decreases in root mass occurred in young plants; however, no changes were detected in mature plants. In all cases, root herbivory resulted in at least a 3.0-fold increase in root 20E concentrations. Our previous experiments implicated jasmonic acid and the analog methyl jasmonate (MJ) in signaling the damage-induced accumulation of root 20E levels. We investigated the activity of other phytohormones and growth regulators (GRs) on the 20E accumulation patterns of young plants as a means of examining the significance of jasmonates in the induction response. Hydroponic additions of MJ (0.5 M) and the synthetic auxin, 1-naphthaleneacetic acid (NAA; 0.5 M), resulted in significant increases in root 20E levels. At the concentrations tested, indole-3-acetic acid (IAA), gibberellic acid (GA₃), abscisic acid (ABA), and trans-zeatin (Z) had no effects on root 20E concentrations. However, both NAA (0.5–5.0 M) and Z (5.0 M) treatments caused increases in the root/shoot dry mass ratios, indicating shifts in resource allocation to the roots. Treatments involving ABA (5.0 M) and Z (0.5–5.0 M) caused significant increases in shoot 20E concentrations. No other hormone treatments altered shoot accumulation patterns. The mechanisms underlying the root 20E induction phenomena were investigated through the incorporation of [2-¹⁴C]mevalonic acid ([¹⁴C]MVA). Within one day, excised roots readily incorporated radioactivity into 20E from [¹⁴C]MVA. In intact plants, [¹⁴C]MVA absorbed by the roots was rapidly incorporated into root 20E pools following damage and MJ treatments. This implies that the wound-induced root 20E accumulation is the result of increased de novo 20E synthesis in the root.     

灵芝茵丝体多糖的超滤提取及其抗氧化活性的研究

考察了超滤浓缩醇沉法提取发酵灵芝茵丝体多糖,与减压浓缩法相比,多糖含量、多糖得率均高于后者,所得多糖的品质得到提高,减轻了后续多糖纯化的负担.灵芝菌丝体粗多糖对羟自由基·OH(HFR)有较好的清除能力,在一定范围内清除率与多糖浓度呈正相关,超滤浓缩醇沉法提取灵芝茵丝多糖的·OH清除率高于减压浓缩醇沉法.     

灵芝菌丝体多糖的超滤提取及其抗氧化活性的研究

考察了超滤浓缩醇沉法提取发酵灵芝菌丝体多糖,与减压浓缩法相比,多糖含量、多糖得率均高于后者,所得多糖的品质得到提高,减轻了后续多糖纯化的负担。灵芝菌丝体粗多糖对羟自由基.OH(HFR)有较好的清除能力,在一定范围内清除率与多糖浓度呈正相关,超滤浓缩醇沉法提取灵芝菌丝多糖的.OH清除率高于减压浓缩醇沉法。     

9种常见植物秸秆抗氧化活性的比较研究

采用DPPH法、α-脱氧核糖氧化法(对·OH的清除能力)和普鲁士蓝法(还原能力)3种方法测定提取物抗氧化活性,比较了9种常见植物秸秆的抗氧化活性。结果显示:凤眼莲叶和法桐落叶在3种测试方法中均显示出了强抗氧化能力,而稻草和麦秆均为抗氧化能力较弱的植物。各种抗氧化能力测试方法之间存在一定的相关性。     

Model studies on the mechanism of endotoxin adsorption on flat-sheet microfiltration membrane adsorbers

The adsorption of endotoxin from E.coli O 111:B₄ and bovine serum albumin on membrane adsorbers with the ligands polymyxin B, L-histidine, deoxycholate, poly(L-lysine), poly(ethyleneimine) and diethylaminoethyl was studied under equilibrium and dynamic conditions. Apparent association constants varied between 30 and 30 000 mL/mg for endotoxin, whereas with BSA only approximately 1 mL/mg was found on average. With all ligands a reduction of the removal efficiency was experienced in the presence of BSA, which was used as model protein. Detailed analysis of the influence of BSA on the association constants as well as the equilibrium and dynamic capacities of endotoxin adsorption demonstrated that endotoxin and BSA molecules recognize distinct binding centres on the membrane adsorbers. Competition for binding sites plays a less important role than assumed so far. It is concluded that interactions of endotoxin with protein molecules in solutions are limiting endotoxin clearance from protein solutions. With net-positively charged proteins, electrostatic interactions yield protein-endotoxin complexes. Net-negatively charged proteins attract endotoxin by the mediation of calcium ions that are derived from endotoxin micelles and vesicles. In the latter case, endotoxin clearance can be significantly improved by the addition of EDTA.     

Phytoecdysteroid Turnover in Spinach: Long-term Stability Supports a Plant Defense Hypothesis

Using short (8-day) and long-term (28-day) experiments, we examined the stability of 20-hydroxyecdysone (20E) and the dominant phytosterols synthesized from a pulse of [2-¹⁴C]mevalonic acid ([¹⁴C]MVA) in hydroponically grown spinach (Spinacia oleracea). In the short-term experiment, plant dry mass and shoot 20E pools steadily increased. Root uptake of [¹⁴C]MVA resulted in the stable incorporation of ¹⁴C radiolabel into whole plant 20E pools, with no significant changes over time. Levels of free and saponifiable phytosterols increased in the shoots while ¹⁴C-labeled shoot phytosterols remained constant. Unexpectedly, both ¹⁴C-labeled and unlabeled pools of root phytosterols decreased over time. In the long-term experiment, plant dry mass and shoot 20E levels increased over time, while total ¹⁴C-labeled 20E pools remained constant. Both root and shoot phytosterol pools increased over time while the ¹⁴C incorporation in these pools remained constant. Together these experiments indicate that 20E in spinach is metabolically stabile and thus shares this characteristic with plant terpenoids of known defensive function. While little is known about phytosterol turnover in plants, our results suggest that phytosterols can indeed exist in a very dynamic state but may also be stable over time.     

响应曲面法优化刺山柑水溶性多糖提取工艺及其抗氧化性能研究

以刺山柑果实为原料,在单因素实验的基础上,选择提取温度、提取时间和液料比为影响因子,以刺山柑水溶性多糖提取率为响应值,应用Box-Behnken中心组合方法建立数学模型,利用响应曲面法确定超声辅助提取刺山柑水溶性多糖的优化工艺条件为：提取温度85℃、提取时间89 min、液料比30∶ 1（mL∶g）,在此条件下刺山柑水溶性多糖平均提取率为8.89％.提取得到的刺山柑水溶性多糖对羟基自由基（·OH）和超氧阴离子自由基（·O2-）均有一定的清除作用,具有一定的抗氧化活性.     

双氰胺脱色剂强化混凝处理印染废水

将双氰胺脱色剂与聚合氯化铝进行复配,对某印染厂的二级处理出水进行强化混凝试验,确定了最佳的混凝剂复配比及混凝条件。研究结果表明:混凝剂的最佳复配比为双氰胺脱色剂0.12 mL/L、PAC 87.5 mg/L,此时脱色率达74%,CODCr去除率达57%,UV254去除率达36%,该复合混凝剂的处理效果良好。     

玉米芯木聚糖硫酸酯的合成、表征及其抗凝血活性

以碱法提取的玉米芯木聚糖为原料,LiCl为催化剂,在非质子溶剂中,采用三氧化硫-吡啶法合成了玉米芯木聚糖硫酸酯（XS）,通过正交试验对合成工艺进行了优化,并采用凝胶渗透色谱（GPC）、红外光谱（FT-IR）、元素分析和¹³C NMR对其结构与性能进行了表征,进一步考察了其体外抗凝血活性。结果表明：在DMF溶剂中,当三氧化硫-吡啶络合物与木糖羟基单元的物质的量之比为1.5：1时,于55℃反应3 h,木聚糖的酯化效果最好,所制备的XS的取代度（D_S）为1.53,得率为78.2%,重均相对分子质量为36 754,分散系数为1.191。结构表征发现,硫酸酯基已经成功引入木聚糖中。体外抗凝血活性结果表明：XS可以延长APTT和TT,具有一定的抗凝血活性;当取代度为1.53、质量浓度为20 mg/L时,XS的APTT、PT和TT分别为36.37、14.22和14.70 s,与阳性对照肝素钠基本相当。     

切削乳化废液的药剂处理及油品回收

优选出化学混凝处理乳化废液的最佳混凝剂为PAC PAM、酸性AlCl3废液，操作条件为pH＝6．0—7．5，投量PAC：1g／L、PAM：40mg／L；酸性AlCl3废液：28mL／L，混凝絮渣经浓盐酸、浓硫酸及酸性废液处理：每升乳化废液混凝产生的絮渣需12mL浓盐酸、4mL浓硫酸及18mL酸性废液，油被溶出约16mL／L，余下的混合液可用来循环处理废乳化液；实现以废治废、清洁生产的目的     

Stabilisation of SWNTs by alkyl-sulfate chitosan derivatives of different molecular weight: towards the preparation of hybrids with anticoagulant properties

We have previously demonstrated that chitosan derivative N-octyl-O-sulfate chitosan (NOSC), which presents important pharmacological properties, can suspend single walled carbon nanotubes (SWNTs) up to 20 times more effectively than other chitosan derivatives in an aqueous environment. In an attempt to further investigate the impact of different molecular weights of chitosan to the solubilization and anticoagulant properties of these hybrids an array of NOSC derivatives varying their molecular weight (low, medium and high respectively) was synthesised and characterised by means of FT-IR spectroscopy, NMR spectroscopy and thermal gravimetric analysis (TGA). Microwave and nitric acid purified SWNTs, characterised by FT-IR spectroscopy, transmission electron microscopy (TEM) and Raman spectroscopy, were colloidally stabilised by these polymers and their anticoagulant activity was assessed. The results revealed that the low molecular weight NOSC coated SWNTs exhibit the highest activity when 0.5 mg mL(-1) NOSC solutions are used, activity which is similar to that of the free polymer. Preliminary studies by exposure of these hybrids to Brine Shrimp (Artemia) cysts revealed no effect on the viability of sub-adult Artemia. Our findings suggest the possibility of tailoring these nanomaterials to bear the required properties for application as biocompatible building blocks for nanodevices including biosensors and biomaterials.     

Binary Adsorption of a Zn(II)-Cu(II) Mixture onto Egeria densa and Eichhornia crassipes: Kinetic and Equilibrium Data Modeling by PSO

The adsorption of Zn(II) and Cu(II) ions onto two dry macrophytes used as biosorbents was investigated in batch systems. All single and binary metal sorption experiments using Egeria densa and Eicchornia crassipes biomasses as biosorbents were performed under constant shaking, at pH 5, with mixed grain size, and drying and sorption temperatures of 30°C. A 20–45 min equilibrium time range was attained with E. densa, whereas a 30–60 min equilibrium time was achieved with E. crassipes. It was also found that the overall adsorption kinetic data was best described by the pseudo second-order kinetic model, and that the intra-particle diffusion model was involved in the sorption process. An extended-to-multi-component Langmuir-type isotherm model and a parameter identification procedure based on the PSO method have been effectively used for the reproduction of the experimental data and the prediction of the maximum adsorption capacities of Zn(II) and Cu(II) ions in a binary metal ion solution. Finally, E. densa and E. crassipes biomasses exhibited opposite metal adsorption affinity order in the Zn(II)-Cu(II) binary system.