超声波辅助提取大枣多糖及其抗氧化活性的研究

摘要I超声波辅助提取大枣多糖及其抗氧化活性的研究摘要大枣多糖是活性多糖之一。近年来，许多学者围绕着大枣多糖的提取分离结构鉴定药理等方面也展开了研究。而大枣多糖的提取方法是首要问题，一种经济有效的提取方法是我们一直探索和研究的。为此，本课题研究了大枣多糖的提取工艺，为大枣多糖进一步的研究与开发奠定基础。超声波是频率大于20kHz的声波，具有波动与能量的双重属性。其振动产生并传递强大的能量给予媒质粒子极大的速度和加速度，加速度随着声波频率的增高而增大。超声波在某些物质中可以比一些电磁波穿透得更深，停留时间也较长，足以使物质中分子加速运动。所以近几年，超声波技术在功效物质的提取方面得到了广泛的重视。基于这个理论，采用了超声波辅助法提取大枣多糖，优化了大枣多糖的超声提取工艺。本试验通过探讨大枣多糖提取的工艺条件，采用单因素试验和L9(34)正交试验设计，研究了不同超声强度、超声时间、pH和料液比等单因素对大枣多糖提取率的影响并优化了提取工艺。采用水杨酸法检测羟基自由基(·OH)，改进的邻苯三酚自氧化法检测超氧自由基(O2-·)，研究了大枣多糖清除·OH和O2-·的效果。结果表明，最佳提取条件为：1:40的料液比，在超声功率144W，pH5.4，超声条件下提取20min。抗氧化活性试验表明大枣粗多糖对·OH具有较好的清除效果，对O2-·有部分清除作用。关键词：大枣多糖，超声波，提取，抗氧化活性ExtractionofJujubePolysaccharidebyUltrasoundMethodandItsAntioxidantResearch摘要IIABSTRACTJujubepolysaccharideisoneofactivepolysaccharide.Inrecentyears,manyscholarshavecarriedonmuchstudyaroundtheextractionandseparationofjujubepolysaccharideinadditionofidentifyingit’sstructureandpharmacology.Whilethemethodofextractjujubepolysaccharideistheprimaryproblem,wehavebeenexploringandstudyinganeconomicandeffectivemethodofextractjujubepolysaccharide.Sowestudytheextractionofjujubepolysaccharideandhopetofindthetheoriestoimproveitsresearchandapplication.Thefrequencyofultrasonicsoundwavesisgreaterthan20kHz,withfluctuationsinthedualpropertyandenergy.Theultrasonicsoundwavescangenerateandtransmitthevibrationenergyofthepowerfulmediaparticlestogivegreatspeedandacceleration,accelerationwiththehighersoundfrequencyincreases.Ultrasoundinsomesubstancescanpenetratedeeperthansomeelectromagneticwaves,andlongerresidencetime,sufficienttoacceleratethemovementofmolecularsubstances.Therefore,inrecentyears,theefficacyofultrasoundtechnologyintheextractionofmaterialhasbeenwidelyattention.Basedonthistheory,thepaperadopttheultrasonicextractjujubepolysaccharideandoptimizetheextraction.Inthispaper,theextractiontechnologyforjujubepolysaccharideandtheirantioxidantactivitieswerestudied.Theeffectofeachfactorsuchastheultrasoundpower,theultrasoundtime,thepHandtheratioofsolid-liquidontheextractionofpolysaccharideinjujubewereinvestigatedusingthemethodsofsinglefactortestandorthogonaldesigntestofL9(34).Thescavengingeffectofjujubepolysaccharideonhydroxylradicals(·OH)and(O2-·)radicalsweretestedbysalicylicacidmethodandimprovedpyrogallolauto-oxidationmethod.Theresultshowedthatthehighestextractionrateofjujubepolysaccharidecouldbeobtainedwitharatioofsolidtoliquidas1:40,144WandpH5.4for20mintoextract.Theanti-oxidationpropertyofexperimentalresultshowsthatjujubepolysaccharidehasobviousantioxidantfunctionto·OHandweaktoO2-·.摘要IIIKEYWORDS:jujubepolysaccharide,ultrasound,extract,antioxidantactivity目录IV目录第一章前言..............................................................................................11.1多糖概述...........................................11.2大枣多糖的研究进展................................11.2.1大枣多糖组成..................................11.2.2大枣多糖的提取方法............................11.2.3大枣多糖的生理活性............................21.3自由基理论........................................31.4常用的抗氧化活性的测定方法........................31.5研究目的和意义....................................41.6研究内容..........................................4第二章大枣多糖的提取..........................................................................52.1单因素试验.........................................52.1.1试验试剂和仪器................................52.1.1.1试验试剂..................................52.1.1.2试验仪器.................................52.1.2试验方法......................................62.1.2.1多糖测定方法与制作标准曲线................62.1.2.2超声波辅助提取大枣多糖工艺参数的确定......62.1.2.3数据处理.......................................72.1.3结果与分析....................................72.1.3.1苯酚-硫酸法测多糖含量的标准曲线...........72.1.3.2超声波辅助提取大枣多糖工艺参数的确定......82.2大枣多糖提取的正交试验...........................122.2.1正交试验设计.................................122.2.2正交试验结果及结果分析.......................12第三章大枣多糖抗氧化活性的研究....................................................143.1大枣多糖清除羟基自由基的测定.....................143.1.1试验试剂和仪器...............................143.1.1.1试验试剂................................143.1.1.2试验仪器................................143.1.2试验方法.....................................143.1.4结果与分析...................................15目录V3.2大枣多糖清除超氧自由基的测定.....................163.2.1试验试剂和仪器...............................163.2.1.1试验试剂................................163.2.1.2试验仪器................................173.2.2试验方法.....................................173.2.3结果与分析...................................17第四章结论与展望................................................................................194.1结论.............................................194.2结论工作展望.....................................19参考文献..................................................................................................20附录..........................................................................................................22致谢........................................................................................................23第一章前言1第一章前言1.1多糖概述多糖(Polysaccharide)又称多聚糖，由单糖聚合而成，是聚合度大于10的极性复杂的大分子，其分子量一般为数万甚至达数百万。多糖随着聚合度的增加，性质和单糖相差越来越