Extraction And Research On Bioactivity Of Raw Toxin Of Ricious

The paper mainly study the deratization by ricin. It takes the white mouse' s activeness experiment as the indicator, study methods and technology of extraction of ricin from the caster bean. Finally, find out the optimum way of extraction, and using the crude extract of ricin, I study the killing efficacy to the white mouse, simulated the plateau rodents to deratization effect appraisal. At last, in the big area applied experiment, this rodenticide has obtained the quite satisfactory effect.Choose caster bean as the raw material, through selects the different extracting agents to soak, after study the bset method of withdrawing ricin by each kinds of t extracting agents , and contrast extracting efficacy under the bset condition, finally determin, the optimum method of extraction is: extracted with 0. 2mol/L PBS (caster bean:PBS, quality volume ratio is 1: 3 (g/ml)), After soak for 24 hours, obtained mixture 4000 rpm centrifugated 30min, degrease carefully, remove the sediment which the centrifugal remains, keep the clear liquid, and use (NH₄)₂SO₄ salted out in the liquid to 80% degree of saturation, After salting-out 24 hours, 10000 rpm centrifugaate 30min, dialysis and vacuum drying, the production rate of ricin (crude extract) is highest, simultaneously this withdraw method also give dual attention to the protein stability and economical efficiency of extraction method. So it precisely is the best craft route which we seeked.Using the ricin (crude extract) to study the white mouse activenessexperiment, finally indicated, the LD50 of ricin which injects to the mouse abdominal cavity is 7. 971 ug/kg , the main component of rodenticide is ricin. After the ricin causes the white mouse to be poisoned, there is not obviously abnormity responded , that is not easy to create the antifeedant phenomenon, that can enhance the killing mouse efficiency. The results shows that racin is a slowly and highly effective toxin since those treated white mouse generally died between 30h and 96h.In view of the host critical mouse—Ochotona curzoniae in the western-north Sichuan plateau, applicated experiment in the big area was taked, using racin as the main componet. the results show the average controlling rates are over 85%. The killing rate for Ochotona curzoniae is about 90% in the plot experiment. Through continuously observation in half month-long, we had not discovered secondary poisoning on natural enemy like hawk. The treated sheep also not obviously to be affected, after prohibition of grazing period, we has not discover the harm to the domestic animal. These all fully explained that, the ricin rodenticide has the safety control in the application.The above findings shows that, as one kind of new rodenticide, the ricin rodenticide has not secondary poisoning, safe and high efficacy. So, it' s a promising rodenticide to apply to wide areas.