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1.
本文选用尼莫地平(nimodipine,NMP)作为模型药物,以魔芋葡甘聚糖(Konjac glucom annan,KGM)为材料制备KGM-NMP药膜,对其在体外不同介质和不同温度下的释药特性进行考察,初步探讨魔芋葡甘聚糖-尼莫地平药膜的体外释放性能。采用扫描电子显微镜观察药膜各个释放阶段的形态及表面结构,药膜呈胶束状,表面平整光滑,个别表面有凹凸状;用药物释放动力学方程拟合药物释放数据曲线,推导建立数学模型,同时结合电镜扫描结果分析,KGM-NMP药膜的溶蚀特性更符合零级动力学方程,释放机制为扩散和骨架溶蚀的协同作用。该药膜在体外具有明显的缓控释作用,24 h内释药稳定。  相似文献   

2.
魔芋葡甘聚糖对柑桔的保鲜效果研究   总被引:5,自引:0,他引:5  
近年来,国内外对柑桔的保鲜研究进展很快,已有许多方法可供生产上选用,其中以化学保鲜法应用最为普遍。但是目前所用的化学保鲜剂很多都有一定的毒性,因此,筛选天然无毒的保鲜剂成了十分迫切的课题。去年,我们在原有化学药品保鲜研究的基础上,对魔芋葡甘聚糖保鲜柑桔的效果进行了试验,并获得了初步的结果。魔芋葡甘聚糖是从天南星科的魔芋(Amorphophallumrivieri)中提取的一种多糖,无毒、无臭、无  相似文献   

3.
以魔芋葡甘聚糖(KGM)凝胶作为铜金属螯合亲和层析的载体一步亲和纯化猪血SOD,得到电泳均一,比活为8622U/mg,纯化倍数为77.8倍的SOD,其回收率为85.4%.探讨了魔芋葡甘聚糖凝胶作为亲和载体的可能性及前景.  相似文献   

4.
以魔芋葡甘聚糖凝胶为载体亲和层析分离纯化猪血SOD   总被引:4,自引:0,他引:4  
以魔芋葡甘聚糖(KGM)凝胶作为铜金属螯合亲和层析的载体一步亲和纯化猪血SOD,得到电泳均一,比活为8622U/mg,纯化倍数为77.8倍的SOD,其回收率为85.4%。探讨了魔芋葡甘聚糖凝胶作为亲和载体的可能性及前景。  相似文献   

5.
60Coγ射线辐照对花魔芋同工酶与品质的影响   总被引:9,自引:2,他引:7  
本文开展了^60Coγ射线辐照对花魔芋酶类与球茎品质影响的研究。结果表明:辐照诱发了花魔芋同工酶谱的变异,经等电聚焦电泳分析,不同剂量处理,酯酶和多酚氧化酶同工酶酶带呈现多态性,有稳定带和可变带,带型和带数的变化从分子水平揭示了魔芋辐射敏感性,是诱变效应和农艺性状突变的分子基础;经采后球茎品质检测,辐照引起了魔芋品质变化,数据分析表明干物质含量、葡甘聚糖含量、葡甘聚糖粘度与辐照剂量均呈二次曲线关系,总生物碱含量与剂量呈线性负相关。以葡甘聚糖的量和质为评价依据,中等辐射剂量范围内的辐照处理可提高魔芋品质。  相似文献   

6.
魔芋葡甘聚糖的分光光度法测定   总被引:8,自引:0,他引:8  
魔芋为天南星科(Araooae)魔芋属(Amorphophallus blume)植物,是唯一大量提供葡甘聚糖(Glucomannan,下称GM)的新兴特种经济作物。魔芋GM是由D-葡萄糖和D-甘露糖主要通过β-1,4糖苷键结合的高分子多糖,在食品、医药、石油、化工、轻纺等工业中有着重要的用途。GM的定量测定虽有过甘露糖腙重量法和斐林试剂沉淀  相似文献   

7.
紫杉醇是目前临床治疗癌症的一线化疗药物,资源紧张,价格昂贵。7-木糖-10-去乙酰基紫杉醇(7-XDT)在红豆杉中含量可达紫杉醇的10倍,脱除木糖基后生成的10-脱乙酰紫杉醇(10-DAT)经乙酰化可生成紫杉醇。通过木聚糖平板对不同菌株进行筛选,从52株供试微生物中,发现27株在木聚糖平板上生长良好。经转化实验筛选,发现一株天蓝色链霉菌(Streptomyces coelicolor YUCM 410115)具有转化7-XDT为10-脱乙酰紫杉醇的能力。菌体细胞经破碎离心后,沉淀及上清液均无转化反应出现,而发酵液的硫酸铵沉淀物则可以转化7-XDT生成10-DAT,表明该菌株能产生一种胞外紫杉醇-7-木糖苷酶,发酵液酶活为6 268U。首次发现天蓝色链霉菌能够产生紫杉醇-7-木糖苷酶,为7-XDT转化生产紫杉醇提供了新的酶源。  相似文献   

8.
魔芋葡甘聚糖磷酸酯化反应的研究(Ⅰ)   总被引:1,自引:0,他引:1  
本文旨在研究干法条件下魔芋葡甘聚糖磷酸化反应,反应温度、时间、pH和磷酸盐用量对酯化反应以及酯化产物粘度的影响.利用红外光谱、X-射线衍射、扫描电镜及旋转粘度计等分析测试手段,探讨酯化产物的结构和性能之间的关系.  相似文献   

9.
魔芋葡甘低聚糖抗氧化性初步研究   总被引:3,自引:0,他引:3  
为了检验魔芋葡甘低聚糖抗氧化功能,本文测定了魔芋葡甘低聚糖体外清除自由基及保护DNA氧化损伤能力,并通过连续两周用不同剂量的魔芋葡甘低聚糖灌胃小鼠,检测其对肝脏和血浆中丙二醛(MDA)含量、超氧化物歧化酶(SOD)、谷胱肝肽过氧化物酶(GSH-PX)活性的影响。研究结果显示:魔芋葡甘低聚糖对超氧阴离子自由基(.O2-)和羟自由基(.OH)有较好的清除能力,能有效地保护DNA免受羟自由基的损伤,并且能有效地降低肝脏中丙二醛水平,提高肝脏和血浆中SOD、GSH-PX的活性。  相似文献   

10.
氨基葡甘聚糖的质粒DNA转染载体作用的研究   总被引:3,自引:0,他引:3  
目的 :发展一种新的半人工合成的质粒DNA转染载体。方法 :用氨基化方法将纯化的葡甘聚糖阳离子化 ,用凝胶阻滞检测法 (gelretardationassayforcomplexformation)观察氨基葡甘聚糖 DNA复合物的形成 ,以及用氨基葡甘聚糖作报告基因质粒pEGFP Cl的载体 ,转染HEK2 93细胞 ,观察转染效率。结果 :葡甘聚糖氨基化后溶液离子强度增大 2 0倍左右 ,氨基葡甘聚糖可与质粒DNA形成复合物 ,形成的复合物转染HEK2 93细胞后 ,报告基因pEGFP Cl获得阳性表达。氨基葡甘聚糖最大至 1 0 %仍未显示细胞毒性。结论 :氨基葡甘聚糖可发展为DNA载体系统 ,在HEK2 93细胞中获得理想的目的基因表达。  相似文献   

11.
Effect of degree of acetylation on gelation of konjac glucomannan   总被引:3,自引:0,他引:3  
Effect of the degree of acetylation (DA) on the gelation behaviors on addition of sodium carbonate for native and acetylated konjac glucomannan (KGM) samples with a DA range from 1.38 to 10.1 wt % synthesized using acetic anhydride in the presence of pyridine as catalyst was studied by dynamic viscoelastic measurements. At a fixed alkaline concentration (CNa), both the critical gelation times (tcr) and the plateau values of storage moduli (G'sat) of the KGM gels increased with increasing DA, while at a fixed ratio of alkaline concentrations to values of DA (CNa/DA), similar tcr and values independent of DA were observed. On the whole, increasing KGM concentration or temperature shortened the gelation time and enhanced the elastic modulus for KGM gel. The effect of deacetylation rate related to the CNa/DA on the gelation kinetics of the KGM samples was discussed.  相似文献   

12.
Gelation behaviour of konjac glucomannan with different molecular weights   总被引:8,自引:0,他引:8  
The deacetylation and gelation of konjac glucomannan (KGM) following alkali addition was investigated by Fourier transform infrared, while the rheological properties of KGM with different molecular weights were studied by dynamic viscoelastic measurements in shear mode and penetration force tests. It was found that gelation occurred after significant deacetylation had taken place. Rheometrical studies revealed that KGM with different molecular weights exhibited different gelation characteristics in small amplitude oscillatory shear flow. For the samples of fractionated KGM with lower molecular weights, a decrease in both the storage shear modulus (G') and loss shear modulus (G") was observed during gelation at temperatures above 75 degrees C. It is suggested that the decrease results from the wall slip between sample and measuring geometry owing to a rapid gelation process with syneresis and/or disentanglement of molecular chains adsorbed on the surface of parallel plates from those located in the bulk. Penetration force tests were employed to confirm the occurrence of slippage and thereby no decreases in rigidity of samples were observed during gelation. For the native KGM samples decreases in G' and G" during gelation were not observed, and it is suggested that this is due to the effect of the higher molecular weight and increased solution viscosity of these samples on the gelation kinetics.  相似文献   

13.
Wang L  Wang A 《Bioresource technology》2008,99(5):1403-1408
N,O-carboxymethyl-chitosans (N,O-CMC) with different degree of substitution (DS) were synthesized under heterogeneous conditions by controlling the reaction temperature. The factors influencing adsorption capacity of N,O-CMC such as the DS of N,O-CMC, initial pH value of the dye solution and adsorption temperature for anionic dye congo red (CR) were investigated. Compared with chitosan (78.90 mg/g), N,O-CMC with the DS of 0.35 exhibited much higher adsorption capacity (330.62 mg/g) for CR at the same adsorption conditions. The adsorption kinetics and isotherms showed that the sorption processes were better fitted by pseudo-second-order equation and the Langmuir equation, respectively. The adsorption mechanism of N,O-CMC was also discussed by means of IR and XPS spectra. The results in this study indicated that N,O-CMC was an attractive candidate for removing CR from the dye wastewater.  相似文献   

14.
The adsorption of congo red (CR) onto chitosan (CS) beads impregnated by a cationic surfactant (CTAB, cetyl trimethyl ammonium bromide) was investigated. Chitosan beads impregnated at a ratio of 1/20 of CTAB to CS (0.05% of CTAB and 1% of CS) increased the CR adsorption capacity by 2.2 times from 162.3 mg/g (0% CTAB) to 352.5 mg/g (0.05% CTAB). The CR adsorption decreased with an increase in pH of the CR solution from 4.0 to 9.0. The Sips isotherm model showed a good fit with the equilibrium experimental data and the values of the heterogeneity factor (n) indicated heterogeneous adsorption of CR onto CS/CTAB beads, as well as CS beads. The kinetic data showed better fit to the pseudo second-order rate model than to the pseudo first-order rate model. The impregnation of CS beads by cationic surfactants showed the highest adsorption capacities of CR compared to any other adsorbents and would be a good method to increase adsorption efficiency for the removal of anionic dyes in a wastewater treatment process.  相似文献   

15.
Gelation behavior of native and acetylated konjac glucomannan   总被引:2,自引:0,他引:2  
Gelation kinetics of native and acetylated konjac glucomannan (KGM) samples in the presence of alkali (sodium carbonate) was studied by dynamic viscoelastic measurements. Molecular weight and other molecular parameters of KGM were determined by static light scattering and viscosity measurements. It was found that KGM molecules were degraded during acetylation treatment, but the molecular weights of acetylated samples were almost independent of the degree of acetylation (DA) and were about a half of that of a native sample. At a fixed alkaline concentration, increasing concentration of KGM or temperature shortened the gelation time, but increasing DA delayed it. The deacetylation reaction and subsequent aggregation process of acetylated samples needed longer time than that of native sample, and acetylated samples formed finally more elastic gels. It implied that the presence of acetyl groups exerts a strong influence on gelation behavior of KGM. It was suggested that the gelation rate of acetylated KGM and native KGM, which depends on the alkaline concentration and temperature, is an important factor that determines the elastic modulus of gels. This was supported by the experimental finding that the saturated elastic modulus tends to the same value when the ratio of alkali concentration to acetylated groups was kept constant. In slower gelation processes, junction zones are more homogeneously distributed and more numerous, leading to the more elastic gels.  相似文献   

16.
将KGM凝胶和Sepharose 4B在同样条件下活化偶联,制成Cu~(2 )金属螫合亲和胶,亲和纯化猪血SOD,并对这两种亲和胶的层析效果和性能进行了比较。KGM金属螫合胶对猪血SOD吸附量、纯化倍数、纯化SOD的比活力和回收率分别为53000U/ml胶、19倍、12000U/mg蛋白和94.6%,而Sepharose 4B亲和胶对SOD 的吸附量、纯化倍数、纯化SOD的比活力和回收率分别为79920U/ml胶、11倍、10125U/mg蛋白和95.4%。两种亲和胶所纯化的SOD经聚丙烯酰胺凝胶电泳(PAGE)、活性染色及SDS聚丙烯酰胺凝胶电泳(SDS-PAGE)证明其均为电泳纯。KGM金属螯合胶使用六次后,其对SOD吸附量、去Cu量及SOD的回收率均无明显影响。  相似文献   

17.
The white rot fungus, Fomes lividus, was isolated from the logs of Shorea robusta in the Western Ghats region of Tamil Nadu, India. The fungus was tested for decolorization of azo dyes such as orange G (50 M) congo red (50 M) amido black 10B (25 M) and also for colour removal from dye industry effluents. The results revealed that the fungus could remove only 30.8% of orange G in the synthetic solution, whereas congo red and amido black 10B were removed by 74.0 and 98.9% respectively. A dye industry effluent was treated by the fungus in batch and continuous mode. In batch mode treatment, a maximum decolorization of 84.4% was achieved on day 4, and in continuous mode a maximum decolorization of 37.5% was obtained on day 5. The colour removal by the basidiomycete fungus might be due to adsorption of the dyes to the mycelial surface and metabolic breakdown. These results suggested that the batch mode treatment of Fomes lividus is one of the most efficient ways for colour removal in dye industry effluents.  相似文献   

18.
为寻找水果上桔小实蝇产卵情况的快速检测方法,本文测定了甲基蓝、龙胆紫、品红、曙红、藏红和刚果红等6种染色剂对水果上桔小实蝇Bactrocera dorsalis(Hendel)产卵孔的染色效果。结果表明染色剂对可疑水果进行染色,若有产卵孔,产卵孔可迅速被染色,染色率最高可达100%。筛选出甲基蓝、藏红和刚果红作为芒果、番石榴和夏橙的最适染色剂,各种染色剂在浓度为0.5%时染色效果较佳,同时对持续冷藏保存后的水果上的产卵孔仍然具有较高的染色率。  相似文献   

19.
Lentinus edodes CCB-42 was immobilized in loofa sponges and applied to the biosorption of the synthetic dyes congo red, bordeaux red and methyl violet. Live immobilized microorganisms achieved average decolorations of congo red, bordeaux red and methyl violet of 97.8, 99.7 and 90.6 %, respectively. The loofa sponge was the support and the coadjuvant promoting dye adsorption. The biosorption conditions were optimized for each dye, yielding 30 °C, pH 5.0 and a 12 h reaction time for congo red; 25 °C, pH 3.0 and 36 h for bordeaux red; and 25 °C, pH 8.0 and 24 h for methyl violet. Operational stability was evaluated over five consecutive cycles, with both bordeaux red and congo red exhibiting decolorations above 90 %, while the decoloration of methyl violet decreased after the third cycle. In the sixth month of storage, congo red, bordeaux red and methyl violet had decolorations of 93.1, 79.4 and 73.8 %, respectively. Biosorption process best fit the pseudo-second-order kinetic and Freundlich isotherm models. Maximum biosorption capacity of heat-treated L. edodes immobilized in loofa sponge was determined as 143.678, 500.00 and 381.679 mg/g for congo red, bordeaux red and methyl violet, respectively. Treatment with immobilized L. edodes reduced the phytotoxicity of the medium containing dyes. FT-Raman experiments suggested the occurrence of interactions between loofa sponge fibers, L. edodes and dye. L. edodes CCB-42 immobilized in loofa sponges represents a promising new mode of treatment of industrial effluents.  相似文献   

20.
A white rot fungus Thelephora sp. was used for decolourization of azo dyes such as orange G (50 microM), congo red (50 microM), and amido black 10B (25 microM). Decolourization using the fungus was 33.3%, 97.1% and 98.8% for orange G, congo red and amido black 10B, respectively. An enzymatic dye decolourization study showed that a maximum of 19% orange G was removed by laccase at 15 U/ml whereas lignin peroxidase (LiP) and manganese dependent peroxidase (MnP) at the same concentration decolourized 13.5% and 10.8%, orange G, respectively. A maximum decolourization of 12.0% and 15.0% for congo red and amido black 10B, respectively, was recorded by laccase. A dye industry effluent was treated by the fungus in batch and continuous modes. A maximum decolourization of 61% was achieved on the third day in the batch mode and a maximum decolourization of 50% was obtained by the seventh day in the continuous mode. These results suggest that the batch mode of treatment using Thelephora sp. may be more effective than the continuous mode for colour removal from dye industry effluents.  相似文献   

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