Detoxification On Adsorption Of Deoxynivalenol In Feed

Deoxynivalenol(DON) is one of mycotoxins which has the high contamination rate in feed and raw materials in recent years, causing great harm to the health of human and animal, bringing great economic losses to the feed industry. Adding adsorbents in the feed is a convenient and efficient method of adsorpting mycotoxins, but the adsorption rate of traditional adsorbents to DON is very low, generally less than 30%. So looking for a adsorbent with effective adsorption to DON is around the corner. This research based on the experiment of the various adsorbents’ adsorption in vitro, selecting the adsorbent with high adsorption rate, studying on its adsorption mechanism, and through animal experiment to explorate the adsorption effect of the adsorbent to DON in vivo.Adsorbents selection: 40 mg adsorbent together with 400μL DON(100mg/L) in the 20 mL buffer system shock 2h, after incubation to detect the adsorption rate of the adsorbents, result shows that the adsorption rate of adsorbent d to DON in vitro is highest, at 82.36%, and the adsorption rate of the adsorbents to DON in vitro is as follows: adsorbent d > adsorbent c > adsorbent b > glucomannan, yeast cell wall in activation, attapulgite, humic sodium, adsorbent a > white carbon > vermiculite. Adsorbent a, adsorbent b, adsorbent c and adsorbent d are optional adsorption materials, they are adsorption properties of porous solid material, and belong to the same kind of material, but come from different sources. Therefore, choose the optional adsorbents with high adsorption rate, especially the adsorbent d for subsequent research. Four kinds of optional adsorbents go through the 20, 40, 60, 80, 100, 120, 140, 160, 140, 200 and more than 200 mesh standard screen respectively after smashing, and the adsorption experiment in vitro is carried out to explore the influence of adsorption rate on different diameter size, result shows that with the particle size of adsorbents from 20 mesh to more than 200 mesh, the adsorption rate increases gradually. The result of adding amount of the adsorbents on adsorption effect to DON shows that when adding amount of adsorbent d is 0.05% adding to 0.6%, its adsorption rate increases 53.15% to 90.57%. Further to explore the adsorption stability of adsorbent d to DON by desorption test. Results show that the desorption rate of adsorbent d was 8.32% after desorpting 4.5h, which shows the adsorbent d has good adsorption stability to DON in vitro. Through scanning electron microscopy(SEM) to observe the surface structure characteristics of the adsorbents, result shows that the adsorbent a has smooth surface and developed pores, distributting some fine scales; adsorbent b has smooth surface with big holes distribut uniformly; adsorbent c has rough surface with some middle holes; adsorbent d has slit pores distributting uniformly on surface.Mechanism of adsorbent d to DON: Through the isothermal adsorption experiment and infrared spectroscopy analysis to explore the adsorption mechanism of adsorbent d to DON. Result shows that the the regression curve of adsorbent d to DON in vitro is in line with the Langmuir equation, the regression equation is: c/Q = 0.0003 + 0.0005 c, R2 = 0.9112, the maximum adsorption quantity Qm is 2000mg/kg, and it ibelongs to monolayer adsorption. When the PH is 7.0, adsorbent d has significant absorption peak of hydrogen bond or the O-H stretching vibration absorption peak in the water(in the wavenumber of 3414 cm-1) before and after the reaction. The IR spectrogram of adsorbent d after reaction under PH 2.0 shifts up obviously, and has absorption peaks in the wavenumber of 1385 cm-1 and 535 cm-1, this shows that the adsorbent’s surface of the nonaqueous O-H in-plane bending vibration and Si-O-Al bending vibration has significantly strengthened, and the chemical changes have taken place in the surface functional groups.So the adsorption of adsorbent d to DON may be existence not only physical adsorption, but also hydrogen bonds adsorption and chemical adsorption.Animal experiment: animal test is carried out using mice as experimental object, to explore the detoxification effect of adsorbent d with high vitro adsorption rate in vivo. Seventy-two 3-week-old(male) Kun Ming mice were divided into six groups at random, with four replicates of three mice each, respectively feeding following the diet: Group Ⅰ-basal diet; Group Ⅱ- basal diet + 0.1% adsorbent d; Group Ⅲ- basal diet + 0.2% adsorbent d; Group Ⅳ- DON contaminated diet; Group Ⅴ- DON contaminated diet + 0.1% adsorbent d; Group Ⅵ- DON contaminated diet + 0.2% adsorbent d, feeding 28 d continuously, records feed intake of mice every day and its body weight every week. At the 28 th day, the mice were slaughtered, the growth performance, viscera index, complete blood count and serum biochemical indexes for analysis. The results show that Group Ⅳcompared with Group Ⅰ, the spleen index increase significantly(P < 0.05); Lymphocyte counts(LYM) and lymphocyte ratio(LY%) reduce significantly(P < 0.05), neutrophilic granulocyte ratio(NE%) increase significantly(P < 0.05); serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) increase significantly(P < 0.05). And the indicators level of Group Ⅴand Group Ⅵ with adsorbent d are back to the control group levels. It shows that the damage to the liver function and immune function in mice caused by DON can be relieved through adding adsorbent d.To sum up, different adsorbents vary greatly on adsorption rate to DON in vitro; the particle size and adding amount have an effect on adsorption rate, the adsorption rate increases with the decreases of the particle size and the increases of the adsorbents’ dosage. Adsorbent d with high adsorption rate to DON in vitro is selscted, which adsorption rate is 82.36%, and it may be related to its peculiar shape slit pore surface and the developed pore structure; the adsorption of adsorbent d to DON in vitro belongs to the monolayer adsorption, and the adsorption of adsorbent d may be existence the physical adsorption, hydrogen bonds adsorption and chemical adsorption. Adsorbents also have good detoxification effect in vivo, the damage to mice caused by DON can be relieved through adding adsorbentd.