Extraction, Isolation, Purification And Insect Resistance Of Flavonoids From Stem And Leaf

Stellera L., Department of Thymelaeaceae chamaejasme species, has analgesic and insecticidal function. In recent years, there’s much study on Stellera chamaejasme,but it mainly focused on the chemical composition and activity of the root. The study on the stems of chamaejasme is little. For this situation, on the basis of previous studies, this experiment studied Stellera chamaejasme leaf and its extraction of flavonoids, isolation and insect studies were also carried out. The extraction process was optimized. The insect resistance of leaf and root extraction were studied as well as each separate phase of Stellera chamaejasme. And avermectin were mixed with ethyl acetate phase of the stems and leaves to determine its anti canola aphid activity,which provides a theoretical basis for deeper understanding and use of Stellera chamaejasme.The experiment focused on insect activity of botanical extracts on rapeseed aphids,in order to be able to carry out biological control of aphids, and reduce the use of chemical pesticides, which can offer new research directions for reasonable control of vegetable pest. Findings of this experiment are as follows :1. This study usded univariate experiment and quadrature experiment to optimize the total flavonoids extraction technology of Stellera chamaejasme stems.The optimum extracting solvent is ethanol. Cold soak method was used with ultrasound-assisted.Quadrature experiments were based on the univariate experiment. The optimal conditions of extraction processes are: solid-liquid ratio 1:25, 90% ethanol soaked,ultrasonic power 800 W, sonication 50 min, rotary evaporation under 70 ℃ for extraction. Finally11.01 percent of the leaf yield of flavonoids was obtained.2. In this study, Stellera chamaejasme shoot and root extracts were separated by column chromatography and two kinds of Flavonoid components were obtained,namely: ethyl acetate and n-butanol phase. Leaf dipping method and insect dipping method were used to research the insect-resistant of crude extract of stems and roots and stems and leaves with ethyl acetate and n-butanol phase and separation of root extracts of different phases. Experimental results show that the difference in insecticidal effect of stems and roots of crude extracts was not significant, the insecticidal effect of stems ethyl acetate phase is better than several other extracts separate phases.3. The experiment assayed anti-aphid activity of avermectin and leaf ethyl acetate phase which were subsequently measured after mixed.The results showed that theethyl acetate phase of stems and avermectin are anti-aphid activity, 0.01 mg / ml ethyl acetate phase of stems and avermectin in 30 h the corrected mortality were 60% and70%; The corrected mortality reached 97% after mixed, which has synergistic function compared with the previous. After the ethyl acetate phase were mixed with avermectin, the effect is significant. Both showed a synergistic effect.