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1、摘要本文重要研究了壳聚糖与芳氧丙酸类除草剂2，4滴丙酸(DCPP)的互相作 用手性差别，并通过壳聚糖分子(CS)及其纳米微粒(NP)在淡水绿藻液中对 2，4滴丙酸毒性及降解的影响，初步揭示了壳聚糖对2,4滴丙酸的手性辨认作用 及其环境生态行为影响。此外，还研究了脂肪酶与2,4滴丙酸互相作用的手性差 异，阐明了脂肪酶对除草剂2，4滴丙酸的手性辨认作用及其机理。重要涉及如下 内容：(1)研究了荧光标记壳聚糖分子及其纳米微粒与2，4滴丙酸的互相作用差 异。成果表白，壳聚糖分子及其纳米微粒与2，4滴丙酸不同对映体之间均可形成 一种结合位点，其结合能力存在手性差别，结合伙用大小均依次为(Js)DCPP(
2、胸-DCPP(R)-DCPP，即壳聚糖分子及纳米微粒对除草剂具有手性辨认，且整体上，壳聚糖纳米微粒对DCPP的结合伙用不小于壳聚糖分子的结合伙用。DCPP 与壳聚糖之间重要以疏水作用力为主，同步也存在静电作用。(2)研究了壳聚糖分子及其纳米微粒在三种淡水绿藻中对除草剂2，4滴丙酸 及其对映体毒性的手性辨认作用成果表白，壳聚糖分子及其纳米微粒在三种绿 藻液中对除草剂2，4滴丙酸均产生了手性辨认作用，且对不同藻类其手性辨认不 同：对一般核小球藻来说其克制作用依次为(R)DCPPCS($DCPPCS(R$DCPP-CS及氓)-DCPP-NP(回一DCPP-NP(脚-DCPP-NP；对斜生桐藻来说其克
3、制作用依次为(JS)DCPPCS职回-DCPP-CS似)-DCPP-CS及(s3DCPP-NP(R$一DCPP-NP俾)一DCPPoNP；对蛋白核小球藻来说其克制作用依次为 (Rs)-DCPPCS一DCPP-CS僻)DCPP-CS及CRs)一DCPP-NP一DCPP-NP (R)一DCPP-NP。壳聚糖分子及其纳米微粒在培养周期内对不同藻类克制作用强度存在差别。 CS、NP对藻类的克制作用顺序均为蛋白核小球藻一般核小球藻斜生栅藻。 此外， 同一种藻类对壳聚糖分子及其纳米微粒的反映也不同样。整体上，对普 通核小球藻来说，在72h内CS的克制作用不不小于NP，而96h后CS的作用则强于 NP；对斜
4、生棚藻来说，cs作用弱于NP；而对蛋白核小球藻来说，CS作用强于 NP。V低浓度壳聚糖分子及其纳米微粒与除草剂2，4滴丙酸作用前后对一般核小 球藻生长均起到增进作用，而高浓度则体现出较强的克制作用，且其克制作用存 在差别，克制作用大小依次为：NPCS)DCPPNP职)DCPPCS 俾)DCPP，且随培养时间的延长其克制作用增强，到96h时毒性减轻。(3)研究了壳聚糖分子在蛋白核小球藻液中对除草剂2,4滴丙酸及其对映体 降解的手性辨认作用。成果表白，壳聚糖分子存在条件下，2，4滴丙酸及其对映 体在蛋白核小球藻液中的残留量浮现了明显增长的现象，即壳聚糖分子减少了除 草剂的降解率。同步，2，4滴丙酸
5、不同对映体与壳聚糖结合后在藻液中的降解存 在手性差别，其降解速率大小依次为：僻)DCPPCS。DCPPCS(RD DCPPCS。这与2，4滴丙酸手性对映体自身在藻液中的降解速度顺序不同，除草剂自身的降解率大小依次为(脚DCPP僻)DCPP($DCPP。手性除草剂2，4滴丙酸在藻液中的半衰期长短不同，其半衰期大小依次为： (回-DCPP俾)一DCPP(兄$DCPP，加入壳聚糖分子溶液后除草剂在蛋白核小球 藻液中的半衰期大小顺序发生了变化，其顺序为：(R)DCPPCS(固DCPPCS职DDCPP(s3DCPP；并 由两者作用过程的热力学参数得知其作用力类型重要为疏水作用，且这种作用可 能是其存在手
6、性差别的重要因素；同步根据同步荧光光谱测定成果可以推测除草 剂与脂肪酶的结合位置更接近于蛋白质分子上的色氨酸残基，它对DCPP-与脂肪 酶之间的手性选择作用也许作出了一定的奉献。且俾S1)DCPP在高浓度时，对 脂肪酶的激活作用十分明显，而(尺)DCPP在低浓度对脂肪酶的克制作用较 强核心词：2,4滴丙酸；壳聚糖分子(cs)；壳聚糖纳米微粒(NP)；手性辨认；毒性；降解；互相作用AbstractThis paper mainly studied the chiral interactons of chitosan and chiral Aryloxycarboxylic herbicide d
7、ichorprop(DCPP)，and the toxicity and degradation changes of DCPP with chitosan moleculars(CS)and chitosan nanoparticles(NP) in three freshwater green algae，preliminarily revealing the chiral recognition and environmental effects of CS and NP on DCPPIn addition，we researched the chiral interactions o
8、f lipase and DCPP，showing the chiral recognition and mechanisms between themThis paper Can be mainly devided into four parts：(1)The enantioselective interactions of fluorescence labeled chitosan molecularS (FCS)and fluorescence labeled chitosan nanoparticles(FNP)with DCPP were studied The results sh
9、owed chitosan and DCPP Can form one binding site，and the chiral selectivity was existed with interaction orders of(回一DCPP僻印-DCPP(R)一DCPEAnd also，the interactions of FNP was stronger than FCS with DCPPFurthermore，themain force between them was the hydrophobic force，and the electrostatic force was als
10、o existed(2)The enantioselective ecotoxicity of陋)-，(印-jS)-DCPP with CS and NP in three algae Was investigatedWe can conclude that CS and NP showed chiral recognition on DCPP in three freshwater green algae，and the chiral recognition Was different witll different algaeFor Chlorella vulgaris the order
11、s of inhibition rateswere (R)一DCPP-CS($一DCPPCS(R固一DCPPCSand 僻)-DCPP姗-DCPP-NPDCPP-NP；for Scenedesmus obliqURN theorders were(S)-DCPP-CS似印一DCPPCS饵)一DCPPCS and(S)-DCPP-NP(尼$一DCPP-NP(R)一DCPP-NP；and for Chlorella pyrenoidosa the orders were(R$一DCPPCS-DCPPCS僻)一DCPPCS and(Rs)DCPP-NP-DCPP-NP(R)一DCPP-NPCS an
12、d NP had different inhibition rates on different kinds of algae，and the order Was Chlorella pyrenoidosaChlorella vulgarisScenedesmus obliquus WhatS more，the same kind of algae showed different responses with CS and NPThe inbihition of CS on Chlorella vulgaris Was weaker than NP in the initial 72h an
13、dVIIstronger than NP after 96hFor Scenedesmus obliquus,CS showed weaker inhibition than NP,but for Chlorella pyrenoidosa CS showed stronger inhibition than NECS and NP with DCPP call promote the growth of Chlorella vulgaris at low concentrations，while inhibite at hi曲concentrationsAnd the inhibition
14、WaS different with the order of NPCS俾)-DCPP-NP)-DCPPCS职)-DCPP Furthermore，the inhibition was increased with the increasing incubation time，but decreased at the time of 96 h(3)The enantioselective degradation of俾)一，一，僻回一DCPP诹th CS in ChlorelIa pyrenoidosa was investigatedThe results showed that the residual ratios of DCPP witll CS compared wil DCPP itself were increased in Chlorella pyrenoidosa ThatS to say，the degradation rates of herbicide were reduced witll CS。Moreover，the chiral selectivity of CS on DCPP and its enantio
