Study on preparation of lycium oil microcapsule using flaxseed gum as wall material

本文采用喷雾干燥法制备沙棘籽油为芯材、亚麻籽胶为壁材的微胶囊,并以微胶囊化效率和含油率为考察指标,考察了制备工艺.结果表明,最佳喷雾干燥工艺条件：进风温度为180℃,出风温度为80℃,雾化器转速24000r/min,进料速度为40.21mL/min.在此工艺条件下沙棘籽油的微胶囊化效率为87.12%,含油率为45.09%.     

Electro-responsive polyacrylamide-grafted-gum ghatti copolymer for transdermal drug delivery application

An application of polyacrylamide-grafted-gum ghatti (PAAm-g-GGH) copolymer for transdermal delivery of an anti-psychotic drug, quetiapine fumerate triggered by electric stimulus was explored. The electro-responsive PAAm-g-GGH was prepared by free radical polymerization underneath nitrogen atmosphere subsequent to alkaline hydrolysis. The PAAm-g-GGH was used as drug reservoir gel and crosslinked films of GGH and PVA as rate controlling membranes (RCM). The reservoir gels were uniform and translucent; pH of gels was 6.56–7.06, which is in the pH range of skin and drug content was from 89.57% to 94.51%. The thickness of RCMs was 163–227?μ; thickness was increased with increased glutaraldehyde concentration and all the RCMs were permeable to water vapors. When electric stimulus was absent, a small amount of drug was permeated from the formulations, while drug conveyance was enhanced in the existence of stimulus. Drug permeation was increased with increase in electric stimulus from 2 to 8?mA. Over two fold increase in flux was observed after application of electric stimulus. Under “on–off” electric stimulus, faster drug permeation was seen under ‘on’ condition and permeation was decreased when stimulus was ‘off.’ Histopathology study confirmed reversible alteration of skin structure under electric stimulus.     

Solutions of xanthan gum/guar gum mixtures: shear rheology,porous media flow,and solids transport in annular flow

Mixtures of xanthan and guar gum in aqueous solution were studied in two flow situations: simple shear and porous media. In addition, solids transport in vertical annular flow of sand suspensions was explored. The zero shear rate viscosity of the solutions displayed a pronounced synergy: the viscosity of the mixture is higher than that of the polymer solutions in a wide range of relative concentrations of the two polymers, in agreement with previous literature. However, at relatively high shear rates, the viscosity approaches the value of the more viscous xanthan gum solutions at mass fractions of xanthan gum between 0.1 and 0.15, and the degree of synergy substantially decreases. Stress relaxation experiments in simple shear indicate that the polymer mixtures exhibit a well-defined yield stress after relaxation that is absent in solutions of pure polymers. In porous media flow experiments, a synergistic behavior mimicking the shear flow results was obtained for the polymer mixtures at low shear rates. However, at a critical shear rate, the apparent viscosity in porous media flows exceeds the shear viscosity due to the elongational nature of flow in the pores. The solids transport capacity in annular flows is well-represented by trends in shear viscosity and stress relaxation behavior. However, the lack of viscosity synergy at high shear rates limits the applicability of the mixtures as a way to improve solids suspension capacity in annular flows.     

基于转录组高通量测序分析白光对杜仲愈伤组织中绿原酸含量的影响

利用Illumina HiSeq 2500平台对光暗培养的杜仲愈伤组织进行了转录组高通量测序,利用BLAST软件进行差异表达基因的功能注释和富集分析,就白光(光强为12 000 lux,16 h 光照,8 h 黑暗)对杜仲愈伤组织中绿原酸含量的影响进行了研究.结果表明:通过Trinity软件合并组装后共获得62 030个Unigenes,通过BLASTX比对,共获得25 417(40.98%)个有注释信息的Unigenes.通过对KEGG通路进行深入分析表明,白光(光强为12 000 lux,16 h 光照,8 h 黑暗)培养杜仲愈伤组织18 d,与绿原酸合成相关的3种酶基因上调表达,它们分别为苯丙氨酸解氨酶(EC 4.3.1.24,phenylalanine ammonia-lyase,PAL)、肉桂酸-4-羟基化酶(EC 1.14.13.11,trans-cinnamate 4-monooxygenase,C4H)、奎宁酸羟基肉桂酰转移酶(EC 2.3.1.133,Shikimate o-hydroxyl-cinnamoyltransferase,HCT).由此推断,白光能促进杜仲愈伤组织中绿原酸的积累.研究结果为获取高产绿原酸资源和杜仲遗传分析提供有价值的资料.     

Synthesis of a New Hydrogel,Based on Guar Gum,for Controlled Drug Release

Summary: Guar gum (GG) polymer was crosslinked in order to obtain a new hydrogel. The GG hydrogel has been characterized by means of FT-IR spectroscopy, the determination of the water content, at different pH values, rheological measurements and in vitro release studies. The GG hydrogel shows a maximum water uptake at acid and basic pH values. The mechanical properties are investigated in order to verify the thixotropic behaviour of the material. In vitro release studies are conducted to evaluate the application of the GG hydrogel as a matrix for controlled drug release.     

羟丙基瓜尔胶的制备及表征

瓜尔胶(guar gum)是一种天然半乳甘露聚糖,其水溶性和增稠性很好,广泛用做增稠剂、破乳剂等。原粉胶溶解较慢、水不溶物含量高、粘度不易控制,人们常利用化学手段改变其理化特性以满足实际工业生产需要,羟丙基化是有效的手段之一,但对羟丙基化的表征较为困难。S．     

邻体干扰推广模型及其在林草生态系统的应用

在对邻体干扰指数模型进行推广的基础上,将其应用于分析林草生态系统（杜仲－三叶草,杜仲－黑麦草,杜仲－蒿类）中杜仲生长速度与草本植物邻体干扰强度的定量关系。     

两次制备薄层色谱分离纯化杜仲叶中的绿原酸

将杜仲叶粉先用氯仿除脂,乙醇超声提取绿原酸,再经适当萃取除杂后、通过两次制备薄层色谱纯化得到绿原酸.产品的紫外光谱特征与文献相符,薄层色谱主斑与绿原酸对照品对应,HPLC的主峰tR与绿原酸对照品的tR吻合.HPLC外标法测得产品绿原酸的纯度为91.6%以上.所建立的纯化制备方法简便、直观、对绿原酸有很好的分离效果,适合于数百毫克级~克级的制备.     

泡沫植物胶特性及其护壁防漏机理

结合某矿区的复杂地质特征,选用4种植物胶进行室内试验遴选,辅以十二烷基苯磺酸钠(ABS)、聚丙烯酰胺(HPAM)、腐殖酸钾为外加剂进行泡沫植物胶基浆配制,探讨植物胶对基浆中膨润土含量、泡沫稳定性能及其流变特性影响的变化规律.研究结果表明:植物胶对膨润土泥浆的流变特性具有明显的改善作用,其防塌护壁作用主要表现为低失水特性、疏水性泡沫吸附孔壁、黏弹性泥饼结构、低流速塞流状态等特性:防漏堵漏作用主要表现为泡沫群体结构屏蔽防漏、泡沫与岩屑聚结充填堵漏、高结构黏度塞流阻流防漏、低密度低压力流体防漏堵漏等特性.     

生物聚合物驱油体系流变性研究

考察了盐、碱、表面活性剂及实验温度对生物聚合物（黄胞胶）驱油体系流变性的影响．研究结果表明，生物聚合物与阴离子表面活性剂（石油磺酸盐）相互作用强烈．在流变性方面体现出良好的协同效应，这种协同效应对低界面张力—流度控制复合驱十分有利．对几类生物聚合物驱油体系，包括聚合物驱、碱－聚合物驱、碱－表面活性剂－聚合驱的不同配方的而变性考察结果表明，在常用的几种描述聚合物溶液流变性的模型中，幂律模型（Ｏｓｔｗａｌｄ模型）的相关性最好