It takes flavonoid extraction rate as indicator and adopts the method of orthogonal experiment to study process of total flavonoid in Trollius chinensis through ultrasonic wave assisted extraction, microwave assisted ...It takes flavonoid extraction rate as indicator and adopts the method of orthogonal experiment to study process of total flavonoid in Trollius chinensis through ultrasonic wave assisted extraction, microwave assisted extraction and backflow extraction, as well as optimization of process parameter. The result indicates that in terms of extraction efficiency, microwave extraction method is better than ultrasonic radiation extraction method, which is better than backflow extraction method. Optimal process parameter through backflow extraction is: backflow temperature 60℃, fluid material ratio 1:20, ethanol density 65%, backflow time 60min; optimal process parameter through ultrasonic wave assisted extraction is: ultrasonic radiation temperature 70℃, fluid material ratio 1:20, ethanol density 65%, ultrasonic wave radiation time 45rain; optimal process parameter of microwave assisted extraction is: microwave radiation temperature 60℃, fluid material ratio 1:20, ethanol density 75%, microwave radiation time 45min.展开更多
Three extraction methods, ultrasonic assisted extraction (USE), microwave assisted extraction (MSE), and conventional single extraction (CSE), in conjunction with the modified three-stage BCR sequential extraction pro...Three extraction methods, ultrasonic assisted extraction (USE), microwave assisted extraction (MSE), and conventional single extraction (CSE), in conjunction with the modified three-stage BCR sequential extraction procedure (SEP) were applied to examine the contents of Cd, Cu, Cr, Ni, Pb and Zn from lake sediment samples, to know whether these techniques can reduce extraction time and improve reproducibility. The SEP and developed alternative single extrac- tion methods were validated by the analysis of certified reference material BCR 601. By the use of optimized sonication and microwave conditions, steps 1, 2 and 3 of the BCR sequential extraction methods (excluding the hydrogen peroxide digestion in step 3, which was not performed with sonication and microwave) could be completed in 15-30 min and 60- 150 s, respectively. The recoveries of total extractable metal contents in BCR 601, obtained by three single extractions ranged from 93.3%-102%, 88.9%-104% and 81.2%-96.2% for CSE, USE and MSE, respectively. The precision of the single extraction methods was found in the range of 3.7%-9.4% for all metals (n = 6).展开更多
采用超声波-微波协同技术对丁香抗氧化活性物质提取工艺进行了优化,并对该技术高效提取机理进行了分析。结果表明,丁香抗氧化活性物质超声波-微波协同提取最佳工艺条件为:50%乙醇、液料比30 m L/g、超声波功率50 W、微波功率100 W、协...采用超声波-微波协同技术对丁香抗氧化活性物质提取工艺进行了优化,并对该技术高效提取机理进行了分析。结果表明,丁香抗氧化活性物质超声波-微波协同提取最佳工艺条件为:50%乙醇、液料比30 m L/g、超声波功率50 W、微波功率100 W、协同提取时间12 min。通过对比分析发现,超声波-微波协同对丁香抗氧化活性物质的提取效率显著高于水浴振荡提取(P<0.01);协同提取技术优势在于超声波和微波的协同作用,实现优势互补,从而对原料细胞结构破坏更严重,作用更充分,提高了提取效率。展开更多
文摘It takes flavonoid extraction rate as indicator and adopts the method of orthogonal experiment to study process of total flavonoid in Trollius chinensis through ultrasonic wave assisted extraction, microwave assisted extraction and backflow extraction, as well as optimization of process parameter. The result indicates that in terms of extraction efficiency, microwave extraction method is better than ultrasonic radiation extraction method, which is better than backflow extraction method. Optimal process parameter through backflow extraction is: backflow temperature 60℃, fluid material ratio 1:20, ethanol density 65%, backflow time 60min; optimal process parameter through ultrasonic wave assisted extraction is: ultrasonic radiation temperature 70℃, fluid material ratio 1:20, ethanol density 65%, ultrasonic wave radiation time 45rain; optimal process parameter of microwave assisted extraction is: microwave radiation temperature 60℃, fluid material ratio 1:20, ethanol density 75%, microwave radiation time 45min.
基金Project supported by the Higher Education Commission of Pakistan (No.Ac-I/GS/963)
文摘Three extraction methods, ultrasonic assisted extraction (USE), microwave assisted extraction (MSE), and conventional single extraction (CSE), in conjunction with the modified three-stage BCR sequential extraction procedure (SEP) were applied to examine the contents of Cd, Cu, Cr, Ni, Pb and Zn from lake sediment samples, to know whether these techniques can reduce extraction time and improve reproducibility. The SEP and developed alternative single extrac- tion methods were validated by the analysis of certified reference material BCR 601. By the use of optimized sonication and microwave conditions, steps 1, 2 and 3 of the BCR sequential extraction methods (excluding the hydrogen peroxide digestion in step 3, which was not performed with sonication and microwave) could be completed in 15-30 min and 60- 150 s, respectively. The recoveries of total extractable metal contents in BCR 601, obtained by three single extractions ranged from 93.3%-102%, 88.9%-104% and 81.2%-96.2% for CSE, USE and MSE, respectively. The precision of the single extraction methods was found in the range of 3.7%-9.4% for all metals (n = 6).