Anhydrous proton conductor consisting of pectin–inorganic composite material

An organic–inorganic proton conductive composite material consisting of a biopolymer was prepared by mixing the pectin, tetraethyl titanate, and imidazole. Although the pectin material without the composite dissolved in water, the pectin–inorganic composite material did not show water solubility. In addition, in the composite material, the pectin and imidazole formed an acid–base structure by an electrostatic interaction, and as a result, these composite materials showed a thermal stability at intermediate temperatures (100–200°C). Furthermore, these composite materials indicated the proton conductivity of 5.6 × 10^?4 S cm^?1 at 180°C under anhydrous conditions. The activation energy of the proton conduction under anhydrous conditions was 0.32–0.22 eV and these values were one order of magnitude higher than that of the typical humidified perfluorinated membrane, such as Nafion^®. The organic–inorganic composite material consisting of a biocomponent may have the potential to be utilized as a novel proton conductor under anhydrous conditions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42433.     

Preparation of modified oligochitosan and evaluation of its scale inhibition and fluorescence properties

To obtain an environmentally friendly and efficient scale inhibitor, carboxymethyl quaternary ammonium oligochitosan (CM‐QAOC) was prepared from chitosan, which was depolymerized by nitrous acid, and then reacted with chloroacetic acid and glycidyl trimethyl ammonium chloride via carboxymethylation and quaternization, respectively. The chitosan derivatives were characterized by Fourier transform infrared and NMR spectroscopy. The inhibition performance for CM‐QAOC was evaluated by a conductivity method and a static antiscaling test. The experiments demonstrated that CM‐QAOC showed an excellent scale‐inhibition performance. With a Ca²⁺ concentration of 240 mg/L, CM‐QAOC at a concentration of 50 mg/L and pH 8.0 gave an antiscaling ratio of more than 98%. So, CM‐QAOC could be applied as an excellent antiscaling agent. Furthermore, a detectable fluorescence of CM‐QAOC solution was observed. To understand this interesting fluorescence phenomenon and to explore the probability of its being a fluorescent tracer, the relations between the fluorescence intensities and CM‐QAOC concentrations and the pH influence on the fluorescence intensities were investigated. The results show the fluorescence intensities accorded well with the concentrations of CM‐QAOC with a detection limit of 0.6046 mg/L, and the fluorescence intensity was constant within pH 5–9; this indicated that it had the potential of its being a fluorescent tracer. Thus, CM‐QAOC could be applied as an antiscaling water‐treatment chemical and as a fluorescence tracer directly without any further modifications. It could be self‐traced online and in real time with its own fluorescence, although more work should be done to investigate its fluorescent mechanism and its tracing properties in detail. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42518.     

Physical and mechanical properties of the fully interconnected chitosan ice‐templated scaffolds

Porous chitosan scaffolds were prepared with a freeze‐casting technique with different concentrations, 1.5 and 3 wt %, and also different cooling rates, 1 and 4°C/min. The pore morphology, porosity, pore size, mechanical properties, and water absorption characteristics of the scaffolds were studied. Scanning electron microscopy images showed that the freeze‐cast scaffolds were fully interconnected because of the existence of pores on the chitosan walls in addition to many unidirectionally elongated pores. Increases in the chitosan concentration and freezing rate led to elevations in the thickness of the chitosan walls and reductions in the pores size, respectively. These two results led to the enhancement of the compressive strength from 34 to 110 kPa for the scaffolds that had 96–98% porosity. Also, augmentation of the chitosan concentration and decreases in the freezing rate led to the reduction of the number of pores on the chitosan walls. Furthermore, the volume of water absorption increased with a reduction in the chitosan concentration and cooling rate from 690 to 1020%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41476.     

苯酚-硫酸显色法测定多糖

芦荟多糖是芦荟的主要生物活性组分,其含量是芦荟制品的重要理化检验指标之一。文章研究了测定芦荟中多糖含量的测定方法。用紫外可见分光计,经苯酚-硫酸显色,对多糖进行测定。该法测定芦荟多糖含量,简单、快速、灵敏,而且结果满意。     

A selective assay to detect chitin and biologically active nano-machineries for chitin-biosynthesis with their intrinsic chitin-synthase molecules

A new assay system for chitin has been developed. It comprises the chitin-binding protein ChbB in fusion with a His-tag as well as with a Strep-tag, the latter of which was chemically coupled to horseradish peroxidase. With the resulting complex, minimal quantities of chitin are photometrically detectable. In addition, the assay allows rapid scoring of the activity of chitin-synthases. As a result, a refined procedure for the rapid purification of yeast chitosomes (nano-machineries for chitin biosynthesis) has been established. Immuno-electronmicroscopical studies of purified chitosomes, gained from a yeast strain carrying a chitin-synthase gene fused to that for GFP (green-fluorescence protein), has led to the in situ localization of chitin-synthase-GFP molecules within chitosomes.     

采用超滤技术浓缩提纯南瓜多糖

研究了超滤技术在南瓜多糖浓缩纯化过程中的应用，发现南瓜多糖的最佳超滤条件是：采用截留分子量30KDa的超滤膜，超滤压力为0．100MPa，超滤温度为25℃。在此条件下，截留率达到94．5％，脱色率迭到68．6％，还原糖脱除率达到82．9％。     

几种新型微生物多糖食品添加剂的性能、应用及发展前景

利用微生物生产食品添加剂已是食品工业中的一个热点应用,本文综述了几种新型微生物多糖食品添加剂的优良性能及其在食品工业中的应用,并展望了其发展前景.     

仙人掌多糖胶囊的制备

以仙人掌浓缩清汁为原料,进行仙人掌多糖的正交提取试验,并将提取的仙人掌多糖制备成多糖胶囊。正交提取实验结果表明,仙人掌汁浓缩5倍,乙醇与仙人掌汁的比例为1∶3,醇析温度为-18℃时,仙人掌多糖的提取得率最高;仙人掌多糖胶囊制备方法:以95%乙醇作为仙人掌多糖的黏合剂制粒,6%～8%HPMC溶于60%乙醇中作包衣液,在35～40℃下包衣,干燥2h后装胶囊,可获得品质较好的仙人掌多糖胶囊。     

枸杞粉及其多糖对环磷酰胺致免疫低下小鼠免疫及肠道菌群的调节作用

枸杞是我国传统的药食两用资源,其鲜果喷雾干燥粉作为食品或功能食品原料被广泛应用,但其功效作用研究较少。本研究以环磷酰胺（cyclophosphamide,CTX）诱导免疫低下的小鼠为模型,探究枸杞粉（Lycium barbarum L. powder,LB）、枸杞多糖（Lycium barbarum L. polysaccharides,LBP）及复配物（LB＋LBP）对小鼠免疫力及肠道菌群稳态的影响。结果表明,LB、LBP及LB＋LBP均可不同程度地恢复免疫抑制小鼠的体质量和采食量,改善小鼠的脾脏、胸腺和结肠组织损伤,有效促进免疫抑制小鼠肿瘤坏死因子（tumor necrosis factor-α,TNF-α）、白细胞介素（interleukin,IL）-1β、干扰素-γ（interferon-γ,IFN-γ）和免疫球蛋白A（immunoglobulin A,IgA）的分泌,调节结肠中免疫相关基因的表达,促进短链脂肪酸（short-chain fatty acids,SCFAs）生成,显著调节Muribaculaceae_unclassified、Muribaculum、Mucispirillum、Helicobacter、Bilophila、Clostridiales等相对丰度（P＜0.05）,逆转CTX诱导的小鼠肠道菌群代谢功能异常,并使其趋于正常。相较于LBP,LB、LB＋LBP还可降低Clostridiales相对丰度,增加有益菌Duncaniella的相对丰度,LB＋LBP还可降低厌氧菌Anaerotruncus的相对丰度。本研究结果将为枸杞精深加工产业中功效针对性健康产品研发和多元化产品开发提供理论依据。     

Isolation, partial characterisation and immunomodulatory activities of polysaccharide from Morchella esculenta

BACKGROUND: Polysaccharides extracted from fungi or algae have shown a variety of medical activities, and the exploitation of polysaccharides for application in pharmacy has been very promising. In this study, the immunomodulatory properties of polysaccharides from Morchella esculenta were investigated to identify immunostimulatory activity and potentially contribute to the therapeutic potential of Morchella esculenta. RESULTS: A water‐soluble polysaccharide, MEP, was obtained from the fermentation broth of Morchella esculenta. Two fractions of this polysaccharide (MEP‐I and MEP‐II) were extracted and purified. High‐performance gel permeation chromatography analysis showed the average molecular weights of two polysaccharides. Structural properties and compositions of these two fractions were examined by Fourier transform infrared and a high‐performance liquid chromatography with an evaporative light scattering detector. Active experiments suggested that the MEP had typical immunostimulatory activity. CONCLUSION: These bioactivity tests showed that the polysaccharides from Morchella esculenta presented significant immune modulating activity, and this finding may offer the basis for the popular use of polysaccharides in functional foods or medicine. Copyright © 2011 Society of Chemical Industry