發(fā)布時間：2018-03-24 16:02

  本文選題：脫氧雪腐鐮刀菌烯醇　切入點：吸附劑　出處：《華中農(nóng)業(yè)大學(xué)》2016年碩士論文

【摘要】：脫氧雪腐鐮刀菌烯醇(Deoxynivalenol,DON)是近年來對飼料及飼料原料污染率最高的霉菌毒素之一,它不僅對人畜健康造成危害,還給飼料業(yè)帶來較大的經(jīng)濟損失。在飼料中添加吸附劑是現(xiàn)行方便、有效的脫毒方法,但傳統(tǒng)的吸附劑對DON的吸附效率都很低,一般均小于30%。因此,尋找一種對DON具有高效吸附率的吸附劑迫在眉睫。本研究通過對眾多吸附劑進行體外吸附試驗,篩選出對DON吸附率高的吸附劑,研究其可能的吸附機制,并通過動物試驗探究其在體內(nèi)對DON的脫毒效果。吸附劑的篩選:取40mg吸附劑和400μL DON標(biāo)準品(100 mg/L)于20mL緩沖體系中,恒溫震蕩孵育2h后,測定各吸附劑對DON的體外吸附率,結(jié)果表明,吸附劑d對DON的體外吸附率最高,為82.36%,各吸附劑對DON的體外吸附率大小依次為:吸附劑d吸附劑c吸附劑b葡聚糖、活化酵母細胞壁、凹凸土、腐植酸鈉、吸附劑a白炭黑蛭石。其中,吸附劑a、吸附劑b、吸附劑c和吸附劑d為一類多孔固體的自選吸附劑,它們屬于同一種物質(zhì)但不同制作來源。因此,選擇具有較高吸附率的自選吸附劑,尤其是吸附劑d進行后續(xù)研究。4種自選吸附劑粉碎后分別過20、40、60、80、100、120、140、160、180、200及200目以上標(biāo)準篩,進行體外吸附試驗探究粒徑大小對吸附劑的體外吸附率的影響,結(jié)果表明隨著吸附劑的粒徑從20目減小到200目以上時,吸附劑對DON的體外吸附率逐漸增大。吸附劑添加量對其吸附效果影響的試驗結(jié)果顯示,吸附劑d的添加量從0.05%增加到0.6%時,其吸附率從53.15%逐漸升高到90.57%。通過解吸試驗探究吸附劑d對DON的吸附穩(wěn)定性,結(jié)果顯示,吸附劑d解吸4.5h的累計解吸率為8.32%,說明吸附劑d對DON的體外吸附作用的穩(wěn)定性較好。利用掃描電子顯微鏡(SEM)觀察吸附劑表面的結(jié)構(gòu)特征,結(jié)果顯示吸附劑a表面光滑、孔隙不發(fā)達,其表面還散布有一些細屑;吸附劑b表面光滑,其上均勻分布著大孔;吸附劑c表面較粗糙,其上分布著一些中孔;吸附劑d的表面排布著均勻且規(guī)則的狹縫形孔隙。吸附劑d對DON的吸附機制:通過等溫吸附試驗及紅外光譜法分析探究吸附劑d對DON可能的吸附機制。結(jié)果表明,吸附劑d對DON的體外吸附的回歸曲線符合Langmuir方程,擬合回歸方程為:c/Q=0.0003+0.0005c,R2=0.9112,最大吸附量Qm為2000mg/kg,其屬于單分子層吸附。PH為7.0下,反應(yīng)前后的吸附劑d均出現(xiàn)強烈的氫鍵或水中的O-H伸縮振動的吸收峰(波數(shù)為3414cm-1處)。PH變?yōu)?.0反應(yīng)后,吸附劑d的IR圖明顯上移,且在1385cm-1和535cm-1處出現(xiàn)明顯的吸收峰,這說明吸附劑d表面非水的O-H面內(nèi)彎曲振動和Si-O-Al彎曲振動有明顯的加強,其表面官能團發(fā)生了化學(xué)變化。因此吸附劑d對DON的吸附除了物理吸附還存在氫鍵吸附與化學(xué)吸附。動物試驗:以小鼠為試驗對象進行動物試驗,探究體外吸附率高的吸附劑d在動物體內(nèi)的實際脫毒效果。將72只3周齡昆明小鼠(雄性)隨機分成6組,每組4個重復(fù),每個重復(fù)3只小鼠,分別飼喂如下日糧:組Ⅰ-基礎(chǔ)日糧;組Ⅱ-基礎(chǔ)日糧+0.1%吸附劑d;組Ⅲ-基礎(chǔ)日糧+0.2%吸附劑d;組Ⅳ-DON污染日糧;組Ⅴ-DON污染日糧+0.1%吸附劑d;組Ⅵ-DON污染日糧+0.2%吸附劑d。連續(xù)飼喂28 d,每天記錄小鼠的采食量,每周記錄其體增重。于試驗第28d屠宰取樣,并對小鼠的生長性能、臟器指數(shù)、全血細胞計數(shù)和血清生化指標(biāo)進行檢測分析。結(jié)果表明,組Ⅳ與組Ⅰ相比,脾臟指數(shù)顯著升高(P0.05);淋巴細胞數(shù)(LYM)和淋巴細胞比率(LY%)顯著降低(P0.05),中性粒細胞比率(NE%)顯著升高(P0.05);血清谷丙轉(zhuǎn)氨酶(ALT)和谷草轉(zhuǎn)氨酶(AST)顯著升高(P0.05)。而添加了吸附劑d的組Ⅴ與組Ⅵ小鼠的上述指標(biāo)均恢復(fù)到對照組水平。這說明,添加吸附劑d對DON造成的小鼠肝功能和免疫功能的損傷有較好的緩解作用。綜上所述,不同吸附劑對DON的體外吸附率差異較大;吸附劑的粒徑大小與添加量對其吸附率有影響,其吸附率隨著粒徑的減小而增大,隨著吸附劑添加量的增大而增大。篩選出了對DON體外吸附率較高的吸附劑d,其吸附率達82.36%,這可能與其表面特有的狹縫形孔隙及發(fā)達的孔隙結(jié)構(gòu)有關(guān);它對DON的吸附屬于單分子層吸附,其既存在物理性吸附,還存在氫鍵吸附與化學(xué)性吸附。吸附劑d在動物體內(nèi)對DON也有良好的脫毒效果,其對DON造成的小鼠毒性損傷有一定的緩解作用。
[Abstract]:Deoxynivalenol (Deoxynivalenol, DON) in recent years is one of the highest rates of mycotoxins in feeds and feed pollution, which not only cause harm to human and animal health, bring greater economic losses to the feed industry. Add in the feed the adsorbent is convenient, effective detoxification method, but the traditional adsorption the adsorption efficiency of DON is very low, generally less than 30%. so to find an efficient adsorbent for the rate of DON is imminent. In this study, through in vitro adsorption test on numerous adsorbents, screened DON adsorption rate, adsorption study the possible mechanism, and through animal test to explore the in vivo of DON detoxification effect. Selection of adsorbents: 40mg adsorbent and 400 L DON standard (100 mg/L) in the 20mL buffer system, temperature shock after 2H incubation in vitro, the adsorption of DON. The results show that the adsorption desorption rate, agent D on DON in vitro adsorption rate was the highest, was 82.36%, the adsorption rate of DON in vitro adsorbent size is as follows: D adsorbent adsorbent adsorbent C B dextran, activation of the yeast cell wall, attapulgite, sodium humate, adsorbent a silica in the vermiculite. A, adsorbent, adsorbent B, biosorbent C and D optional a kind of porous solid adsorbent, they belong to the same species but different production sources. Therefore, with optional adsorbent high adsorption rate, especially adsorption agent D for further study of.4 kind of optional adsorbent crushing after 20,40,60,80100120140160180200 and more than 200 mesh sieve effect standard, in vitro adsorption test to explore the particle size of the adsorbent in adsorption rate, the results showed that with the adsorbent particle size decreases from 20 mesh to 200 mesh above, the adsorption rate of DON adsorbent in vitro Increase the amount ofadsorbent. The experimental results show the influence on the adsorption effect, adsorption amount of agent D increased from 0.05% to 0.6%, the adsorption rate and adsorption stability, increased from 53.15% to 90.57%. on the adsorbent D DON through desorption experiment results showed that the cumulative desorption of adsorbent D desorption rate of 4.5H 8.32%, this shows that the stability of in vitro adsorption agent d to DON better. By using scanning electron microscopy (SEM) structures were observed on the surface of adsorbent, the results showed that the adsorption agent a smooth surface, pore developed, its surface is also interspersed with some fines; adsorbent B smooth surface, which are evenly distributed macroporous adsorbent; C rough surface, the distribution of some in the hole; the arrangement of agent D adsorbed on the surface of the slit shaped pore and uniform rules. The adsorption mechanism of the adsorption agent D on DON: by isothermal adsorption experiments and infrared spectroscopy analysis Study on adsorption mechanism of D adsorbent DON. The results showed that with the Langmuir equation of regression curve in vitro adsorption of D on DON, the regression equation is: c/Q=0.0003+0.0005c, R2=0.9112, Qm, the maximum adsorption capacity is 2000mg/kg, which belongs to the monolayer adsorption of.PH was 7, O-H stretching vibration absorption peak before and after adsorption reaction the agent D showed strong hydrogen bond or the water (wave number 3414cm-1) to 2.PH after the reaction, the adsorption was shifted to IR agent D, and appeared in the 1385cm-1 and 535cm-1 absorption peaks, indicating that the adsorbent D O-H table surface non water bend vibration and bending Si-O-Al the vibration significantly strengthened, chemical changes have occurred in the surface functional groups. So the adsorption on DON adsorbent D besides physical adsorption and chemical adsorption of hydrogen bonds also exist. Animal experiment: mice were used as experimental objects for animal experiment, inquiry body 澶栧惛闄勭巼楂樼殑鍚擱檮鍓俤鍦ㄥ姩鐗╀綋鍐呯殑瀹為檯鑴辨瘨鏁堟灉.灝，

本文編號：1659010