修复前后Vero细胞调控草酸钙晶体生长的差异

采用扫描电子显微镜(SEM)和流式细胞仪等多种方法研究了降解大豆多糖(SPS)对损伤的非洲绿猴肾上皮细胞(Vero)的修复作用;研究了修复前后Vero调控草酸钙(CaOxa)晶体形成的差异。经H2O2氧化损伤的Vero在被SPS修复后,其细胞活力、细胞外SOD活性及细胞内线粒体膜电位均增加,细胞形态逐渐恢复到接近正常细胞。在诱导草酸钙(CaOxa)晶体生长过程中,修复细胞可以减少棱角尖锐的一水草酸钙(COM)晶体生成,诱导更多的二水草酸钙(COD)晶体。三种状态Vero诱导的晶体尺寸从小到大顺序为:正常细胞<修复细胞<损伤细胞。本文结果表明,降解大豆多糖可以修复受损伤的Vero细胞,降低肾结石形成的危险性,提示SPS有可能是一种潜在的绿色防石药物。     

Complexation of bovine serum albumin and sugar beet pectin: Stabilising oil-in-water emulsions

In a previous study (Langmuir 28 (2012) 10164-10176.), we investigated the complexation of bovine serum albumin (BSA) with sugar beet pectin (SBP). A pH-composition phase diagram was established and structural transitions in relation to the phase diagram during complexation were identified. The present study examines the implications of these interactions on the emulsifying performance of BSA/SBP mixtures. Middle-chain triglycerides (MCTs) in water emulsions were prepared using conditions corresponding to different regions of the phase diagram. At high pHs and in the stable region of mixed individual soluble polymers where complexation is absent, there is no improved emulsifying performance, compared with the individual protein and polysaccharide. For these mixtures, the emulsion characteristics are controlled by the major component in the solutions, as determined by the competitive adsorption of the two components at the oil-water interface. At low pHs and low BSA/SBP ratios, and so mainly within the stable region of intramolecular soluble complexes, BSA/SBP mixtures greatly improve the stability of emulsions. Here, stabilisation is controlled by the cooperative adsorption of the two components at the oil-water interface. Through electrostatic complexation BSA promotes the adsorption of SBP on to interfaces to form a thick steric layer around emulsion droplets and thus providing better stability. At low pHs and high BSA/SBP ratios, that is, mainly within the unstable region of intermolecular insoluble complexes, emulsions prepared are extremely unstable due to bridging flocculation between emulsion droplets.     

紫心甘薯多糖对四氯化碳肝损伤小鼠的保护作用

研究紫心甘薯多糖对四氯化碳(CCl4)诱导小鼠免疫性肝损伤的保护作用及可能作用机制.以不同剂量的紫心甘薯多糖200、400、800 mg.(kg.d)-1分别给予小鼠灌胃,设立对照组,连续10 d作预处理,腹腔注射0.1%的CCl410 ml.kg-1建立CCl4诱导小鼠肝损伤模型.测定血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、乳酸脱氢酶(LDH)酶活力、总胆红素(TBIL)、总蛋白(TP)含量,测定肝组织中超氧化物岐化酶(SOD)、谷胱甘肽(GSH)、丙二醛(MDA)水平,并进一步观察肝组织病理组织学变化.紫心甘薯多糖各剂量组均能明显地抑制血清中ALT、AST、LDH、TBIL的升高和TP的下降,降低肝脏中MDA的含量,提高肝组织中SOD和GSH活性,减轻CCl4对肝脏细胞的病理损伤.紫心甘薯多糖对CCl4致小鼠急性肝损伤具有明显保护作用,其作用机理可能与抗氧化作用有关.     

鬼毛针中碱溶多糖的结构和生物活性

鬼毛针多糖;抗肿瘤活性;鬼毛针中碱溶多糖的结构和生物活性     

螺旋藻胶囊中氨基酸和多糖含量测定

用发光光度法测定了螺旋藻胶囊中总氨基酸和多糖的含量。结果表明本定量方法准确可靠,可用于控制该产品质量指标。     

甲基纤维素(MC)疏水作用的电化学研究

应用电化学循环伏安法, 以电活性小分子亚甲基蓝(MB)为探针, 研究了不同温度下修饰在玻碳电极表面的甲基纤维素(MC)凝胶的疏水性. 研究发现, 在45～70 ℃温度范围内, MB在MC凝胶修饰电极上的式电位E⁰⁽较相应的裸电极均正移, 氧化峰电流i_pa和还原峰电流i_pc分别较相应裸电极增大, 且随温度升高而增大. 这些结果表明MC分子之间发生了疏水相互作用, 且随温度的升高, 疏水作用增强. 此外, 在上述温度下, MC凝胶修饰电极上峰电流的比值i_pc/i_pa均小于1, 为0.70, 且没有观察到MB单独的吸附峰, 因此MB分子在凝胶修饰电极上发生了弱吸附. 本文研究显示电化学方法是研究该类多糖凝胶机理的一个补充手段.     

Vapor‐Based Synthesis of Poly[(4‐formyl‐p‐xylylene)‐co‐(p‐xylylene)] and Its Use for Biomimetic Surface Modifications

Summary: The vapor‐based synthesis and characterization of a reactive polymer, poly[(4‐formyl‐p‐xylylene)‐co‐(p‐xylylene)] ( 1 ), have been reported. The reactive polymer coating enables the immobilization of oligosaccharides via the chemoselective aldehyde‐hydrazide coupling reaction.

     

Effect of Coconut Protein and Xanthan Gum,Soybean Polysaccharide and Gelatin Interactions in Oil-Water Interface

We report on our study of the interactions between coconut protein extracted from coconut meat and three hydrocolloids (gelatin, xanthan gum, and soybean polysaccharide) and their interfacial adsorption and emulsification properties. We used Zeta potential, fluorescence spectroscopy scanning and ITC to investigate the interactions between a fixed concentration (1%) of coconut protein and varying concentrations of hydrocolloid. Through the interfacial tension and interfacial viscoelasticity, the interfacial properties of the hydrocolloid and coconut protein composite solution were explored. The physical stability of the corresponding emulsion is predicted through microstructure and stability analysis. Xanthan gum forms a flocculent complex with coconut protein under acidic conditions. Soy polysaccharides specifically bind to coconut protein. Under acidic conditions, this complex is stabilized through the steric hindrance of soy polysaccharides. Due to gelatin-coconut protein interactions, the isoelectric point of this complex changes. The interfacial tension results show that as time increases, the interfacial tensions of the three composite solutions decrease. The increase in the concentration of xanthan gum makes the interfacial tension decrease first and then increase. The addition of soybean polysaccharides reduces the interfacial tension of coconut protein. The addition of xanthan gum forms a stronger elastic interface film. Emulsion characterization showed that the gelatin-added system showed better stability. However, the addition of xanthan gum caused stratification quickly, and the addition of soybean polysaccharides also led to instability because the addition of polysaccharides led to a decrease in thermodynamic compatibility. This research lays the foundation for future research into coconut milk production technology.     

决明子有效成分的提取

决明子的主要功能化学成分有蒽醌类、吡酮类和多糖等，具有降血脂、降血压、保肝、通便等作用。本文采用乙醇提取决明子中的三种有效成分：多糖、蒽醌、黄酮。对乙醇浓度、浸提温度、浸提时间、固液比、浸提次数进行了单因素梯度实验，确定了其条件范围，通过进一步正交实验得到决明子有效成分的乙醇提取工艺的最优因素组合．乙醇浓度50％，浸提温度60℃，浸提时间2．5h，固液比l：20。     

Determination of the compositions of polysaccharides from Chinese herbs by capillary zone electrophoresis with amperometric detection

In this paper, capillary zone electrophoresis with amperometric detection (CZE-AD) was applied to determine the compositions of hetero-polysaccharides from Chinese herbs, Angelica sinensis and flax by analyzing their hydrolyzed monosaccharides: fucose, galactose, glucose, arabinose, rhamnose and xylose. Under the selected optimum conditions, the six monosaccharides could be perfectly separated within 25 min and showed significant current responses at copper electrodes. The linear ranges of the six monosaccharides were all from 5.0 x 10(-6) to 2.0 x 10(-4) mol L(-1) and their detection limits were lower or near 1.0 x 10(-6) mol L(-1) (S/N = 3). Experiments showed that the Angelica sinensis polysaccharide was composed of fucose, galactose, glucose, arabinose, rhamnose and xylose (mole ratio 1.0:13.6:15.0:8.7:21.3:3.7), and the flax polysaccharide was composed of galactose, glucose and arabinose (mole ratio 1.0:4.98:1.1). The purity of these polysaccharides leached by the introduced leaching method was 98.3 and 97.6%, respectively. Analyzing polysaccharides by this method has some merits of speed, simple instrumentation and operation, high sensitivity and high reproducibility.