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1、超声波辅助萃取法,汇报人：张娜 小组成员：徐世鑫 宋茜 2015年10月16日,01,02,Contents,目,录,01,超声波辅助提取介绍,超声波辅助萃取法,定义：超声波萃取（UItrasound extraction，UE），亦称为超声波辅助萃取、超声波提取，是利用超声波辐射压强产生的强烈空化作用、扰动效应、高加速度、击碎和搅拌作用等多级效应，增大物质分子运动频率和速度，增加溶剂穿透力，从而加速目标成分进入溶剂，促进提取的进行。,超声波辅助萃取法,基本原理：超声波能量利用高频率的机械振动波在弹性介质中传播，同时加速介质质点的运动频率传递到提取液中引起提取液分子的高频运动，使被提取物质和提
2、取溶剂利用超声波的能量加速分离。此外，超声波产生的空化作用相当于微观的爆破作用不断地将被提取物轰击出原物料，使其充分分离加速浸取速率以达到高效提取的目的。,基本原理,空化效应,当声波通过液体时, 液体各处的声压会发生周期性的变化,相应地, 液体中的微泡核也会随超声频率发生周期性的振荡，形成我们常说的空化效应。微泡破裂和空穴瞬间闭合时，内部气体和蒸汽快速绝热压缩，产生极高的温度和压力，此时的瞬间高温高压能导致游离基和其他组分的形成。,机械效应,超声波在介质中的传播可以使介质质点在其传播空间内产生振动，从而强化介质的扩散、传播，这就是超声波的机械效应。超声波在传播过程中产生一种辐射压强，沿声波方向
3、传播，对物料有很强的破坏作用，可使细胞组织变形，植物组织蛋白变性；同时，它还可以给予介质和悬浮体以不同加速度，且介质分子的运动速度远大于悬浮体分子的运动速度。从而在两者间产生摩擦，这种摩擦力可使生物分子解聚，使细胞壁上的有效成分更快地溶解于溶剂之中。,热效应,超声波在介质的传播过程中，其声能不断的被介质的质点吸收，介质将所吸收的能量全部或大部分转变成热能，从而导致介质本身和药材组织温度的升高，增大了药物有效成分的溶解速度。由于这种吸收声能引起的药物组织内部温度的升高是瞬间的，因此可以使被提取的成分的生物活性保持不变。,其他次级效应,此外，超声波还能产生许多次级效应，如乳化、扩散、击碎、化学效应
4、等，这些作用也促进了植物体中有效成分的溶解，促使药物有效成分进入介质，并与介质充分混合，加快了提取过程的进行，并提高了药物有效成分的提取率。,LOREM IPSUM DOLOR,工艺简单，可提高生产速度，降低企业生产成本，增加经济效应,技术操作方便，萃取完全，能充分利用中药资源，能节约成本,不用或者少用萃取剂，减少萃取剂的污染,无需加热，不会改变所提及成分的化学结构，适用于低温成分萃取,萃取后在某种超声波作用下还可能出现新的物质，有利于发现新的物质,增加所萃取成分的产率，缩短萃取时间,超声波辅助萃取的优点,超声波萃取机,超声波萃取机由两部分组成：超声波萃取系统 和超声波驱动系统。萃取系统：主要
5、包括超声波换能器、超声波变幅杆、超声波工具头用于产生超声波振动，并将此振动能量向液体中发射。驱动系统：（超声波发生器）产生高频高功率电流，驱动超声波振动部件工作。,简单实验流程,新鲜番茄清洗去梗初步破碎超声波破碎提取冷却静置真空抽滤分液处理实验分析,02,文献学习,Literature Learning,Contents,highlight and innovation,Introduction,experimental method and statistical analysis,Experiment,discussion and conclusion,Conclusion,1, anti
6、oxidant epidemiology fat-soluble easily degraded,2,3,Introduction,solvent extractionSCFE time consuming low efficiency costiler price,conventional extraction,properties of ultrasound,properties of lycopene, Multistage effect Increase material molecular motion greater enetration higher throughput,mod
7、ified ultrasonication techniqueUltrasonic assisted extraction(UAE); Protection of the solute; Statistical technique:The response surface methodology (RSM); High-performance liquid chromatography(HPLC).,Experiment,Washed tomatoes were cut into pieces and pulps, homogenised,Homogenised tomatoes were f
8、reeze-dried,Freeze-dried tomato sampleand and mixture solvents (n-hexane, acetone, ethanol) was added into the conical flask,Ultrasonic assisted extraction (37 kHz),the flask was cooled to room temperatureand the mixture was filtered,ultrapure water was added to the filtrate and centrifuged,Experime
9、ntal design, a software (Version 9.2, SAS Institute Inc., Cary, NC, USA) central composite rotatable design (CCRD),Analysis of experimental data:UAE,48min,The interactions between the independent variables on the relative yield of lycopene from tomato are shown in Figs.,80.0(v/w),Analysis of experim
10、ental data:Non-UAE,Figs. show the interactions between the independent variables on the relative yield of lycopene from tomato in the absence of sonication.,where X1 = extraction time (min), X2 = extraction temperature () and X3 = solvent:freeze-dried tomato sample (v/w).,93.35% of the variability i
11、n the response could be explained by the model.,The fit model analysis,the validityof the model since there is a non-significan (p = 0.2698) lack of fit.,HPLC analysis,High-performance liquid chromatography (HPLC) chromatogram of tomato extract using isocratic mobile phases of methanol/MTBE/ethyl ac
12、etate (30:60:10, v/v/v) at 501 nm with flow rate of 1.2 mL/min.,Conclusion, The improved UAE with the aid of RSM provides a rapid mean of estimating the relative lycopene yield during its extraction from tomatoes. From the ridge max analysis, the optimised conditions were 45.6 min (total extraction
13、time), 47.6 (extraction temperature) and 74.4:1 v/w (ratio of solvent to freeze-dried tomato sample). The average relative lycopene yield obtained was 99%. The all-trans lycopene extracted was 5.11 0.27 mg/g dry weight with slight isomerisation (3.19 0.81%) taking place.In addition, comparison study between sonicated and nonsonicated sample runs indicated that ultrasound enhances the extraction yield of lycopene from tomato by 26% on the average of 6 replications at the coded level (0, 0, 0).,谢谢聆听,THANK YOU FOR YOUR ATTENTION,
