超临界流体CO_2提取虎杖中的有效成分

以大黄素为指标对虎杖中的有效成分进行超临界流体CO2萃取。用正交设计法考察了最优萃取条件。影响超临界流体萃取率的主要因素依次是:动态流量、温度、压力、时间;确定了大黄素的最佳萃取条件是:萃取压力25 MPa,萃取温度55℃,动态流量8 kg/h,萃取时间30 m in。超临界流体萃取大黄素的提取率达0.36%。     

PBS/天然虎杖提取物复合材料的界面作用及其性能

将天然虎杖提取物(PCSZ)与可生物降解材料聚丁二酸丁二酯(PBS)复合,为了提高两者之间的相容性,采用硅烷偶联剂KH–550对提取物进行预处理,通过分子模拟阐明了PCSZ,KH–550与PBS间的界面作用,探讨了界面作用对PBS/PCSZ,PBS/KH–550改性PCSZ(PCSZ+K)复合材料性能的影响。结果表明,PCSZ只与PBS进行了共混,偶联剂对提取物进行预处理时,其乙氧基发生了水解。分子模拟表明提取物与PBS能够形成C=O…H—O;而偶联剂与提取物之间首先形成H—O…H—O,再通过偶联剂有机官能团—NH2与PBS形成静电吸附,同时未与偶联剂作用的提取物仍可与PBS形成C=O…H—O,增强了界面结合强度。PBS/PCSZ+K复合材料的混合能和Huggins参数相对于PBS/PCSZ复合材料更低,其相容性更好,使得PBS/PCSZ+K复合材料的热稳定性、拉伸性能、疏水性均较PBS/PCSZ复合材料有所提高。     

超临界CO2萃取虎杖中有效成分的研究

探讨了用超临界CO_2萃取中药虎杖中有效成分(白藜芦醇苷、白藜芦醇和大黄素)的可行性。采用了不同的虎杖预处理方式,并在不同的萃取条件下,用超临界CO_2对虎杖中的有效成分进行萃取研究。考察了各实验因素对超临界CO_2萃取效果的影响,并得到了较好萃取效果的条件。     

虎杖中抗氧化成分的提取分离及其活性研究

提取了虎杖中具有抗氧化活性的总蒽醌(TA),并从总蒽醌中依次分离出强酸成分(SAP)、中酸成分(MAP)和弱酸成分(WAP)。然后采用二苯代苦味酰自由基(DPPH)法对不同质量浓度的TA、SAP、MAP和WAP进行了抗氧化活性测定。TA、SAP、MAP和WAP质量浓度分别为0.2 g/L、0.5 g/L、0.8 g/L、1.2 g/L时,对自由基的最大清除率依次分别为:29.5%、67.1%、85.7%、87.5%;34.0%、74.2%、86.5%、95.4%;9.8%、24.0%、35.2%、47.3%;6.5%、11.1%、19.6%、19.9%。TA、SAP、MAP和WAP对自由基均有程度不同的清除作用,其中SAP的效果最佳,当其质量浓度为1.2 g/L时,最大清除率可高达95.4%。     

虎杖天然染料提取及对大豆蛋白织物染色

对虎杖天然染料提取及其在大豆蛋白织物上的染色性能进行探讨.实验结果表明:虎杖天然染料色泽随pH值变化而改变,其合适的染色工艺参数为pH 4～6,温度95℃,时间60 min;经过不同媒染剂处理后,大豆蛋白织物呈现出不同的色泽;未经固色处理色牢度一般,而经固色剂处理后色牢度可达到3级或3级以上.     

Optimization of extraction and determination of emodin from Polygonum cuspidatum Sieb. et Zucc. products by HPLC-DAD

A uniform experimental design procedure was used to investigate the effects of some operating parameters on the extraction of emodin from Polygonum cuspidatum Sieb. et Zucc. products. Variables tested were volume ratio of material to solvent, size of material, extraction time and temperature and composition of extraction solvent （mixtures of acetone-water）. Each variable was tested at seven levels; 7 experiments were performed in random order. Analyses of the extracts were performed by high-performance liquid chromatography with diode array detection（HPLC-DAD）. Analytical responses were processed by using a forward regression analysis, in order to find polynomial function describing the relationship between variables and responses. For all the analytes the experimental conditions for providing the highest extraction yield inside the experimental domain considered were found. Finally, a simple, rapid and accurate analytical method was developed for the determination of emodin by high performance liquid chromatography. The separation is achieved within 25 rain on an ODS column using methanol and water as gradient mobiles. Emodin can be quantified by using external standard method detecting at 436 nm. Good linearity is obtained with correlation coefficient exceeding 0.9986 and the detection limit and the quantification limit are 1.53 and 3.23 mg/L respectively. This method shows good reproducibility for the quantification of the emodin with intra-day and inter-day relative standard deviation less than 2.3% and 5.6% respectively. Under optimized extraction conditions, the recovery of the standard is 96.5%. The validated method is successfully applied to quantify the emodin in seven Polygonum cuspidatum sieb. Et zucc. products, which provided an idea for the pre-treatment of determination of active compounds in traditional Chinese medicines.     

大孔吸附树脂对虎杖中白藜芦醇吸附性能的研究

本文研究了多种大孔吸附树脂对白藜芦醇的吸附与脱附性能，从中选出H103树脂具有较大吸附量和解吸率。动态吸附实验研究了提取液浓度、pH、流速对H103树脂吸附量的影响，适合的上柱浓度为0．7157mg／ml，上柱液的pH为4．10，上柱液流速为2BV／h。4倍树脂床体积的80％乙醇以1BV／h的流速进行洗脱即可基本将白藜芦醇完全从H103树脂上解吸下来。     

微生物酶法从虎杖中提取白藜芦醇的研究

用微生物发酵法酶解虎杖,可以提高从虎杖中获取白藜芦醇的得率.通过对多种含糖甙键水解酶菌株的筛选,获得四株可以直接作用于虎杖的优良菌株.其中用 Aspergillus niger 1分解虎杖,提取白藜芦醇,与传统醇提工艺和自酶解法相比,提取率明显提高.     

大孔树脂对虎杖白藜芦醇的静态吸附动力学研究

选择18种大孔树脂,比较其对虎杖白藜芦醇的吸附和解吸性能,筛选出较优的4种大孔树脂,通过研究其静态吸附动力学特性,进一步筛选出适合分离虎杖白藜芦醇的理想树脂,并考察洗脱剂浓度对其解吸率的影响。结果表明,HPD400、HPD600、HPD720、HPD722树脂有较大的吸附容量和较高的解吸率,其中HPD722树脂显著优于另外3种,其最大吸附量为48.31 mg/g树脂,吸附平衡常数为0.619 1h-1,具有良好的静态动力学特性;用80%乙醇溶液洗脱吸附饱和的HPD722树脂,其解吸率可达89.59%。     

从虎杖中提取白藜芦醇的工艺研究

采用溶剂从虎杖中提取白藜芦醇,用紫外分光光度法测定含量。研究了不同溶剂、温度、料液比等各种因素对提取率的影响。结果表明,较优的提取条件为:60%乙醇为提取剂,提取温度为50℃,料液比1∶40,提取时间2.5 h,一次提取率达2.38%。按此工艺提取,粗品中白藜芦醇含量高。