The Extraction Process And Bioassay Of Insecticidal And Antibacterial Activity Of Substances From Ambrosia Rtemisiifolia L.

This selection selected ragweed (Ambrosia rtemisiifolia L.)for the study,it is alien invasive plant that widely distributed in our country. Through the extraction process, bioassay test, safety tests and stability tests,discusses and demonstrates the development potential of the ragweed as botanical insecticide antimicrobial pesticide formulations, and lay the groundwork for industrial processes and production of formulation.The extraction of ragweed's antibacterial activity of insecticidal substances shows that, through comparing 5 different methods of the extracting rate of ragweed bold property, and contrasting the effects of insecticide extract dilution, analying the significance of insecticidal test, selected the ultrasonic extraction as the most economical and practical extracting method. Compared and optimized the factors of the selected Ultrasonic extraction, Finalized Ultrasonic extraction as the conducting method of ragweed's antibacterial activity of insecticidal substances, Using 200ml of 90% Anhydrous ethanol,40min as the best extraction by Ultrasonic extraction.Biological test on ragweed's antibacterial activity of insecticidal substances shows that,Taking the method of constant spray to do the indoor Toxicity Measurement for neustrias, Lethal concentration LC50 is 4174.539mg/L, correlation coefficient is 0.9908,closely related. Taking the method of impregnation to do the indoor Toxicity Measuremen for pine moth, lethal concentration LC50 was 6643.69 mg·L-1,the correlation coefficient is 0.9712,closely related.Making mycelial growth inhibition test on three kinds of forest pathogens, lethal concentration EC50 on Mongolica Shoot bacteria was 4742.811 mg·L-1,the correlation coefficient r is 0.9861,lethal concentration EC50 on Poplar Skin bacteria is 1629.046 mg·L-1,the correlation coefficient r is 0.9901.the statistical test on efficacy of the forest cover cage of ragweed dilution on pine moth, the control efficacy of 10-fold dilution made to leaf pine forest is 67.42%,20 times of the control efficacy is 61.8%,40 times of the control efficacy is 43.82%,80 times of the control efficacy is 31.46%,the control effect of 160 times is poor, only accounts for 6.74%,comparing with the indoor Toxicity Measurement,significantly less effective, to achieve the laboratory level,we must increase the concentration.The Safety study of ragweed's antibacterial activity of insecticidal substances shows that, lethal concentration LC50 of dilution of ragweed extracts on the red carp was 970.25 mg/L, the correlation coefficient r is 0.9936,closely related.Under China's current pesticide toxicity grading criteria, Ragweed extracts is the low toxicity level, lethal dose LD50 of dilution of ragweed extracts on the mouse was 7748.822mg·kg-1,according to pesticide toxicity grading criteria, which is Micro-toxic, therefore,it is harmless for the ecological environment,aquatic life and mammals,it can be developed as a botanical pesticide use.Formulation of ragweed's antibacterial activity of insecticidal substances shows that, dilution of ragweed bold property changes with storage time,efficacy also changes, the efficacy changed little within 9 months, the efficacy decreased significantly more than nine months. Heating the drug through electric constant temperature drying oven, analized the influences of different temperature on the ragweed's stability of biologically active substances, inferred that ragweed had a high thermal sensitivity of bioactive substances, its efficacy will be decreased significantly when the temperature exceeds 40℃. Through the light stability test, ragweed bold material has a certain photosensitivity and poor light stability, therefore, the operation should be avoided exposed in the bright light,and preserved in brown bottles, It should be dark in the extraction process, we should select the approach of drying in the shade in the process of drying raw materials.