简介:将初始体质量(0.42±0.05)g的杂交鲟(Acipenserschrenckii♀×A.baerii♂)仔鱼饲养在室内循环水养殖系统中,投喂添加0(G1)、0.25%(G2)、0.5%(G3)、0.75%(G4)和1.0%(G5)L-丙氨酰-L-谷氨酰胺(L-AG)的5种等氮饲料,每个处理3个重复,每个重复1500尾鱼,研究L-AG水平对杂交鲟体成分和十二指肠形态的影响。56d的养殖结果表明:饲料中添加0.25%和5.0%L-AG对全鱼粗蛋白含量影响不显著(P〉0.05),但添加0.75%和1.0%L-AG显著提高了全鱼粗蛋白含量(P〈0.05)。添加0.25%~1.0%L-AG对全鱼水分、粗脂肪和灰分含量影响不显著(P〉0.05)。与对照组相比,添加0.25%~1.0%L-AG对肠道绒毛高度、微绒毛高度和肌层厚度均未产生显著影响(P〉0.05)。结果表明:外源补充0.75%~1.0%L-AG可显著提高杂交鲟仔鱼粗蛋白含量,但添加0.25%~1.0%L-AG对十二指肠形态不产生显著影响。
简介:Defenceproteinsareakindofchemicaldefencecompounds.Theyplayakeyroleinplantrestrainingbioticandabioticharm.Toilluminateactivitiesofsomedefenseproteinsassociatedwithageorplantfamilyoflarch,thelarchneedleswerecollectedfromtwodifferentfamiliesofKoreanlarch,Larixolgensisandahybridlarch,L.kaempferi×L.gmelinii,respectively,andthentheactivitiesofdefenceproteinsinthoseweretestedusingaUVspectrophotometry.Theresultsshowedthattheactivitiesofprotectiveenzymesatthe16-/17-and19-year-agegroupswerehigherthanthoseattheotheragegroupsinthebothlarchspecies.Whiletheactivitiesofpolyphenoloxidase(PPO)atthe16-/17-year-agegroupandphenylalanineammonia-lyase(PAL)andproteaseinhibitorsatthe19-year-agegroupwerethehighestamongallagegroups.Then,comparedwithL.olgensis,thehybridlarchhadsignificanteffectsontheactivitiesofprotectiveenzymes.TheeffectsofplantfamilyontheactivitiesofPALandchymotrypsininhibitorweresignificantlydifferent,andthenthoseontheactivitiesofPPOwerenotsignificantlydifferent.TheeffectsofthetwofamiliesinL.olgensisontheactivitiesoftrypsininhibitor(TI)weresignificantlydifferent,whilethoseinthehybridlarchontheactivitiesofTIwerecontrary.Toconclusionsshowedthatthedifferentageandplantfamilysignificantlyaffectedtheactivitiesofdefenceproteinsintheneedlesoftwolarchspecies,andthenenhancedthelarchresistancetopests.Thesecouldplayakeyfunctioninforestrytreegeneticimprovementandmanagementinfuture.
简介:为探索以D-甘露糖与氨基酸的美拉德反应制备Amadori化合物的可行性问题,以D-甘露糖和L-色氨酸为原料合成了1-L-色氨酸-1-脱氧-D-果糖,利用IR、NMR和HR-MS对产物进行了结构表征,采用单因素试验和正交试验优化了合成工艺,利用在线裂解气相色谱/质谱联用(Py-GC/MS)法研究了产物的热裂解行为。结果表明:(1)最佳合成条件为:当L-色氨酸投料量为30mmol时,反应温度65℃、反应时间6.0h、物料比1:1(D-甘露糖与L-色氨酸的物质的量比)、催化剂用量0.5mmol及溶剂用量80mL,此条件下产率达到45.2%;(2)无论有氧或无氧条件下裂解,产物种类均随温度升高而增加,有氧条件裂解产物种类多于无氧条件;在600℃有氧条件下,1-L-色氨酸-1-脱氧-D-果糖裂解生成具有花香、烘烤香、坚果香、焦糖香等香韵的产物;(3)以D-甘露糖和L-色氨酸为原料合成1-L-色氨酸-1-脱氧-D-果糖的技术方法可行,产品收率较高。