下载

2下载券

加入VIP
  • 专属下载特权
  • 现金文档折扣购买
  • VIP免费专区
  • 千万文档免费下载

上传资料

关闭

关闭

关闭

封号提示

内容

首页 蔬果汁及葡萄酒中甲醇生成、减量

蔬果汁及葡萄酒中甲醇生成、减量.doc

蔬果汁及葡萄酒中甲醇生成、减量

陈松茂
2019-05-23 0人阅读 举报 0 0 0 暂无简介

简介:本文档为《蔬果汁及葡萄酒中甲醇生成、减量doc》,可适用于领域

蔬果汁及葡萄酒中甲醇生成、減量及其細胞毒性之研究Astudyontheformationandreduction,cytotoxicityofmethanolinfruitandvegetablejuicesandgrapewine研究生:侯智耀 Hou,ChihYao指導教授:陳裕鏞 Chen,YuYawn 王裕泰 Wang,YuhTai江啟銘 Jiang,ChiiMing 吳明昌 Wu,MingChang【摘要】本論文分成三個部分來探討蔬果中甲醇之生成、降低方法與毒性第一部分探討蔬果中甲醇之生成第二部分探討酚酸類降低葡萄酒甲醇含量之可行性第三部分探討甲醇之細胞毒性。第一部分:蔬果中甲醇生成之探討首先將種市售蔬果之鮮榨蔬果汁在不同存放溫度與時間條件下果膠酵素對蔬果汁中甲醇生成之影響。結果顯示蔬果榨汁後隨存放時間增加甲醇的生成亦有逐漸增加之趨勢其中以鮮榨的蕃茄汁(±mgmL)與貯藏後的蕃茄汁(℃下貯藏小時為±mgmL℃下貯藏小時為±mgmL)具有最高的甲醇含量。將鮮榨蔬果汁分別儲存於℃和℃下分鐘後分析其理化特性並將數值進行多元回歸分析結果顯示:在果汁中甲醇的釋放與PE活性和PAL活性呈現正相關而與總果膠含量呈現負相關在蔬菜汁中甲醇的釋放則與以PE活性、pH值和可滴定酸呈現正相關與PG活性呈現負相關。此外HMCLAIS果膠親和性膠體分離之晚崙西亞橙(VPE)為一耐酸型之PE在pH~仍具有~的活性因此添加到葡萄酒釀造模式系統中(pH約為~)經過天發酵後導致甲醇含量由±ppm增加至±ppm(VPEX)或±ppm(VPEX)。由於大部分水果果汁之pH介於~顯示此類耐酸型PE的活性愈高對於果汁中甲醇含量的影響愈大。第二部分:酚酸類降低葡萄酒甲醇含量之可行性研究在葡萄酒釀造模式系統之實驗發現添加香豆酸(coumaricacid)或没食子酸(gallicacid)到商業果膠酵素溶液中可以降低甲醇的生成感官品評結果顯示:添加香豆酸組之酒液整體接受度為最佳其次為没食子酸組。為了解酚酸類物質對於商業果膠酵素中PE的動力學表現本文以酚酸類混合商業果膠酵素或HMCLAIS管柱分離純化之PE探討其酵素動力學反應結果發現香豆酸與没食子酸對商業果膠酵素中PE及經過分離純化之PE酵素之抑制反應均為混合型非競爭性抑制(mixedtypenoncompetitiveinhibition)。第三部分:甲醇細胞毒性之探討首先分析Clone正常老鼠肝細胞株、HepGCA人類肝癌細胞株以及ARPE人類視網膜正常細胞株對於甲醇之毒性反應經過hrs反應Clone、HepGCA和ARPE的LD分別為mM、,mM和,mM。以倒立顯微鏡觀察細胞型態的變化發現當甲醇濃度超過,mM時細胞數量有減少的現象當濃度達,mM時細胞明顯減少且有死亡懸浮的狀況產生甚至有呈空泡的現象但在~,mM濃度下皆未觀察到凋亡小體。在~,mM甲醇濃度下隨甲醇濃度提高細胞內ATP含量有下降的趨勢然而LDHrelease則有增加之現象。以流式細胞儀分析發現:甲醇並不會導致細胞產生明顯的subG峰亦不會對細胞DNA的含量造成影響。以蛋白質體學分析甲醇對細胞之影響發現甲醇會引起HepGCA和ARPE細胞蛋白質點含量變化然因濃度效應因此後續探討甲醇細胞毒性之研究建議甲醇代謝產物之細胞毒性並分析鑑定蛋白質點以瞭解甲醇攝取後對體內細胞之毒殺影響。關鍵字:蔬果汁、葡萄酒、甲醇、果膠酯酶、細胞毒性【Abstract】Thepresentpaperdividesintothreepartstodiscusstheproduction,reductionandtoxicityofmethanolinfruitsandvegetablesInPartone,theproductionofmethanolinfruitsandvegetableswereinvestigatedInParttwo,thefeasibilityofusingphenolicacidstoreducemethanolcontentofwinewasstudiedAndinPartthree,thecytotoxicityofmethanolwasdiscussedPartOne:AstudyonmethanolproductionoffruitsandvegetablesThemethanolcontentsoffreshsqueezedjuicesfromfruitsandvegetablesweredeterminedThemethanollevelsabovemgL(thegivenlimitofalcoholicbeverages)weredetectedinfreshtomatojuices(squeezedandstored)andseveralotherstoredjuicesincludingpeashootjuices(afterminstorage),starfruitjuices(afterminstorage),papayajuices(afterminstorage),pineapplejuices(afterminstorage),Valencia(afterminstorage),andalfalfasproutjuices(afterandminstoragesfor℃and℃,respectively)Afteranalyzingwithmultipleregressions,methanolaccumulationwaspositivelyrelativetoenzymeactivitiesofPEandPAL,whilenegativelyrelativetoPGactivityandtotalpectincontentinfruitjuicesInvegetablejuices,methanolaccumulationwaspositivelyassociatedwithPEactivity,pHvalueandtitratableaciditywhilenegativelyassociatedwithPGactivityOneacidtolerantPE,VPE,wasisolatedfromValenciabyHMCLAISaffinitychromatographywithresidualactivityatpHIndayfermentationofwinemakingmodelsystem(pH),themethanolcontentofVPEXgroupandVPEXgroupincreasedfrom±to±ppmandto±ppmrespectivelywhileVPEwasaddedMostofpHvaluesinthejuicesfromfruitsareamongHence,theacidtolerantPEexertsmuchmorecontributioninmethanolaccumulationoffruitsPartTwo:AstudyonthefeasibilityofusingphenolicacidstoreducethemethanolcontentinwineInwinemakingmodelsystem,anobviousdiminishofmethanolcontentwasobservedwhileaddingphenolicacid(coumaricacidorgallicacid)tocommercialpectinenzymesFromthedataofsensoryanalysis,thewineofcumaricacidaddinggroupexhibitsthegreatestoverallacceptanceandthengallicacidaddinggroupTheenzymekineticsresultsshowedthatgallicacidandcoumaricacidexhibitmixedtypenoncompetitiveinhibitionagainstcommercialpecticenzymeandisolatedPEPartThree:AstudyoncytotoxicityofmethanolEffectofmethanoltoxicityonmurineprimaryhepaticcell,humanheptatomacellandhumanretinalpigmentepitheliumprimarycellwasinvestigatedTheresultsshowedthattheLDofmethanolonClone,HepGCA,ARPEwasmM,,mM,,mMseparatelyafterhrincubationTheresultsofmorphologychangesfrominvertedmicroscopeshowedthatcellnumberreducedwhilethemethanolcontentwashigherthat,mMasthemethanolcontentreached,mMthecellnumbersreducedsignificantlyandthesuspensionofsomedeathcellsappearedorevenvacuolephenomenonNeverthelesstherewasnotanyapoptoticbodyoccurredwhenthecontentwasintherangeof,mMWhenthecontentofmethanlwasintherangeof,mM,theATPcontentincelldroppedgraduallyasthemethanolcontentincreasedbutrelatively,theLDHreleasingrespondedtothemethanolcontentinanoppositewayByusingflowcytometry,wefoundthatnotonlymethanolwouldnotinducecellstoproducesignificantsubGpeakbutalsoitdidnothaveanyeffectonthecontentofcellDNAByusingproteomicanalysistoanalyzetheeffectofmethanoloncells,wefoundthatmethanolwouldcausechangesinthecontentofproteinspotofHepGCAandARPEcellsHowever,duetotheconcentrationeffectinthisstudy,thecytotoxicityofmethanolmetabolitesandtheireffectsonproteinspotsaresuggestedinthefuturestudiestounderstandtheeffectofmethanolintakeonthebodycells 

用户评价(0)

关闭

新课改视野下建构高中语文教学实验成果报告(32KB)

抱歉,积分不足下载失败,请稍后再试!

提示

试读已结束,如需要继续阅读或者下载,敬请购买!

评分:

/6

VIP

在线
客服

免费
邮箱

爱问共享资料服务号

扫描关注领取更多福利