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Plant relative to traditional physical and chemical drugs snail snail control in terms of economically efficient, ecological environmental protection, utility continued and other significant advantages of using plants snail schistosomiasis has a very broad application prospects. To dig our snail plant resources, increase schistosomiasis plant prevention efforts, and select important economic species, the the traditional soil pesticides - Chinese tallow object its schistosomiasis, snail effective active ingredient extraction, separation and identification, as well as based on biochemical and ultrastructural angle snail control mechanism to carry out comprehensive and systematic analysis of research methods and basis for scientific evaluation and the rational use of snail control plants. The specific content and conclusions are as follows: 1, crude extract through four different solvents in different organs of the Chinese tallow tree roots, branches, leaves, and seeds schistosomiasis good snail found that the Chinese tallow different organs display Chinese tallow tree species is an excellent snail plant material. Comparisons of different organs, new leaf crude extract snail best, and the same time, for the previous year's deciduous, it still showed good control of schistosomiasis, Tallow Leaves steady snail characteristics; its optimum solvent is petroleum ether. The new leaf petroleum ether extracts Baptist kill the 3d, 4d, 5d LC50 were 20.327,7.125,5.724 mg / L, deciduous petroleum ether extract were 37.570,18.248,9.446 mg / L. The new leaf petroleum ether extract dip kill 5d the LC90 of 24.409 mg / L, deciduous petroleum ether extract 69.922mg / L. New leaf petroleum ether extract compared to deciduous petroleum ether extract showed better snail activity, but a new leaf and deciduous petroleum ether extract schistosomiasis reach the effective molluscicides standard of WHO regulations, that the crude the concentration is less than 100 mg / L should have a fungicidally effective spiro activity requirements. Application chromatography, thin layer chromatography separation and purification the new petroleum ether leaf extract results show that the best separation Florisil packed column eluting, and petroleum ether extract snail substance The separation is concentrated in a narrow area, i.e. in the experiment 496-526 collection tube (concentrated Postscript to A12). The separation of the A12 further found that a group of snail activity ,54-56 classified in the same concentration and environmental conditions under the most concentration of 30 mg / L dip Kill 3 days the snails the mortality rate of 100%; followed by 100-250 tubes, up to 90%; again for 41-50 tube, is 80%. Showed that these tubes contain snail active substance. 3, using the GC-MS method of the sample concentrate with snail activity of the less polar, and the lower boiling substances, separation and identification of the relevant compounds, OK 3,7,11,15 - tetramethyl -2 - en - 1 - cetyl alcohol, palmitic acid, 9,12,15 - 18-enoic acid methyl ester, 1,2 - phthalate, bis (2 - ethyl hexyl acrylate), 8,11,14 - ene - Twenty acid (8,11,14-Eicosatrienoic acid) may be main snail substances. 4, using the HPLC-TOFMS method were analyzed and identified on the four samples having a snail activity polarity, the higher boiling material, from the viewpoint of the common aspects of the compound, C44H58N2O3, C24H42N2O8, C25H44N6O13, C22H43NO and C20H36N4O5 several The component probability of occurrence is high, wherein C44H58N2O3 in four different samples were found to exist in the three samples, C24H42N2O8, C25H44N6O13, C22H43NO and C20H36N4O5 present in both samples. These ingredients may snail activity. 5, the biochemical mechanism of snail research shows that: ① glycogen, with the increase in the concentration of the treatment solution and treatment time, the snails body glycogen content significantly reduce. Concentration of 10 mg / L and 20 mg / L, 30 mg / L and 40 mg / L, 50mg / L A12-2 processing immersion kill snails 96 hours, muscle glycogen content were lower than the control 40.9%, 49.8%, 61.5%, 63.3% and 72.5%, respectively. Analysis: A12-2 impact the snails of liver function, the local hepatic necrosis, directly affect the synthesis of glycogen; certain enzymes in the process of activation or passivation glycogen metabolism, promote glycogen decomposition and inhibition of glycogen synthesis, resulting in glycogen content decreased; affect gastrointestinal function, causing reduced food intake, reduced cellular uptake of glucose and glycogen synthesis decline is the main reason. ② protein, the snails head foot and livers total protein content after 24h ~ 96h treatment showed decreasing trend to reduce → increased →. Treatment liquid when the onset of action, the the SNAIL total body protein content gradually decreased to 48h after rise up to 1.726 g / L and 1.997 g / L, respectively, which may be due to the SNAIL by A12-2 stimulation treatment in vivo metabolism, thereby generating the result of a large number of specific proteins in order to overcome such adversity stress. With time, the snails total body protein content and falling until more than a snail physiological threshold impact energy metabolism and the individual activity decreased gradually to death. ③ related enzymes, alkaline phosphatase, succinate dehydrogenase, aspartate aminotransferase activity in the A12-2 processing solution, with the processing time and the increase in concentration, showed a significant decrease → slow rise → trend significantly reduced. This change in the trend of the three enzymes and organisms are completely based on the normal and pathological stress reaction. And alanine aminotransferase single trend showed a continuous decrease with increasing time, treatment solution has a more direct inhibition of alanine aminotransferase. 6 snail ultrastructure Mechanism: ① the snails head, antennae and foot external structure, scanning electron microscopy, processing snail 24h, 72h after two concentration of 15mg / L, 30mg / L measured dip to kill time and concentration increased, the the snails head and tentacles by the surface of the folds is very obvious to the structures destroyed, flattened, and the emergence of the erosion was significant deformation and surface, severe ulcer loss. Foot began to swell, and was followed by erosion material, ulceration deformation, and can be seen etched holes, surface fluff off, and eventually severe deformation, fission ulcer hurt phenomenon significantly. ② of Oncomelania internal liver structure, transmission electron microscopy, after 15mg / L concentration of A12-2 treatment solution to deal with 24h after the snails were determined to show that the liver cells showed swelling of the nucleus nuclear membrane deformation, a large number of lysosomes, and the partial melting enzyme generally vacuoles. Some mitochondria showed swelling was long and narrow shape, small the part shown vacuoles cristae fuzzy lesions. Chaotically distributed and swelling of the rough endoplasmic reticulum. With the increase of processing time, a large number of middle and late lysosomal, as well as a large number of small vacuoles, nucleus swelling, nuclear material scattered distribution, has been deformed mitochondria, nuclear membrane disappears due to autolysis, had become the vacuoles phenomenon obvious. ③ After processing immersion kill snails, liver cell mitochondria a fuzzy crest of the lesions snails oxidative phosphorylation process greatly affected. Rough endoplasmic reticulum damage will cause the whole body of metabolic disorders. This and after treatment, the snails in vivo alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, succinate dehydrogenase and glycogen content changes coincide. SNAIL via the A12-2 after treatment, the cells within the liver cells, the destruction of the membrane structure, mean that the decline of liver function, hepatic qualitative damage, destruction of the cell structure and function, eventually lead SNAIL death. 7, the present study, the analysis identified tallow tree snail substance, 3,7,11,15 - tetramethyl -2 - en-1 - cetyl alcohol, C44H58N2O3 possible snail compounds, reveal the Chinese tallow snail mechanism that the the tallow tree snail substances snails soft tissue, liver cell structure and metabolism, enzyme activity has a serious injury or inhibition results fully demonstrated the Chinese tallow tree is a valuable excellent plant snail resources.
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