Study On Extraction And Separation Of Active Ingredients For Biological Pesticide From Melia Toosendan Sied.Et Zuce

There are many insect-killed active substances in Melianceae plant, which can be made into pesticide. Those insect-killed active substances is promising to be developed as pesticide, owning to the advantages of effectively killing injurants instead of non-target critters, being easy to decompose without polluting environment and breaking ecology balance. To develop the inartificial ecotypic pesticides, the dissertation focuses on the research of extraction and separation of the active substances in the barks and the fruits of Melia toosendan Sied.Et Zucc which is unique to Chongqing.Different methods including poaching extraction, soxhlet extraction, microwave extraction and ultrasonicwave extraction were employed to extract toosendanin from the basts of Melia toosendan Sied.Et Zucc in the experiments. Some factors affecting toosendanin extraction rate were discussed in mass transfer theory, and the conditions to extract toosendanin were optimized. The studying results show that extraction rate by poaching extraction can reach to 3.2 mg·g-1, by soxhlet extraction to 3.87 mg·g-1, by ultrasonicwave extraction to 3.25 mg·g-1, and by microwave extraction to 3.82 mg·g-1. Purity of toosendanin can arrive at 81.02% by extracting with chloroform. The single-step balance extraction rate is 81.12%, and toosendan can be extracted completely by 5-step extraction. The analyzing results by RP-HPLC show that RSD to examine toosendanin is 0.55% and the recovery rate is 98.18－102.88％, which indicate that the precision is as high as the veracity. The extracts of fructus toosendan, the fruit of Melia toosendan Sied.Et Zucc, also has the capability in killing insects. The active ingredients in fructus toosendan had been separated and examined. In the process, 1000g fructus toosendan were crushed at first and then extracted respectively with petroleum ether, chloroform, ethyl acetate and ethanol. After condensing, 11.5g, 15.0g, 3.5g, 40.5g extracts were respectively obtained. And then various extraction substances were analyzed and examined. Firstly, the petroleum ether extract was examined by GC-MS. The result shows that there are over twenty ingredients in it, almost of which are hydrocarbon while a few are ketone, hydroxybenzene, and amine etc. Secondly, hydroxy value, ester and acid in the chloroform extract were examined. The results show that hydroxy value is 750.51mgKOH·g-1, saponification value is 35.14 mgKOH·g-1and acid value is 12.79%. It was also found that there exist lots of complex ingredients in the chloroform extract after being separated by thin-layer chromatography and by column chromatography. After separating many times, two kind of pure substances were obtained. Examining by UV, IR and HPLC, these two pure substances are unsaturated hydrocarbon and unsaturated ester.