Studies On 10% Microemulsion And 15%Emulsion In Water Of Extracts From Periploca Sepium

In recent years, the active ingredients and insecticidal activities of root bark of Periploca sepium have been detailed studied by Pesticide Institute of Northwest A&F University. In order to directly develop and use this valuable insecticidal plant resources, the studies of processing to microemulsion (ME) and emulsion in water (EW) using its root bark methanol extract has been carried out in this thesis.By choosing the optimal organic solvents, co-surfactant, and surfactant system for ME and EW, periploca sepium 10% ME and 15%EW were successfully developed. ME constitute and ratio are 10% root bark extract, 5% DBS-ca (Pesticide Emulsifier (PE) 500#), 10% PE 400#, 18% Methyl alcohol, 15% Cyclohexanone, and 42% water. EW constitute and ratio are 15% root bark extract, 4% TX-5, 3% BY-140, 1% PE 400#, 27% Methyl alcohol, 8% Cyclohexanone, 42% water.ME technician indexes are as follows: extract content 10% (W/W), in which the main active ingredient periplocoside T content 0.08%; appearance homogeneous yellow transparent liquid; PH 5 to 7; transparent temperature range -5 to 70℃; miscible with water, no any precipitation and suspension; 54±2℃storage 14 days,main active ingredient periplocoside T decomposition rate less than 8%.Technical indexes accord with the requirements of commodity pesticide.EW technician indexes are as follows: extract content 15% (W/W), in which the main active ingredient periplocoside T content 0.12%; appearance milky white; Standard hard water diluted 200 times no precipitation ; 54±2℃storage 14 days, The technician indexes of 15% EW are as follows: appearance milky white; Standard hard water diluted 200 times, no precipitation; 54±2℃fourteen days storage, main active ingredient periplocoside T decomposition rate less than 5%; precipitation water less than 10%. Technical indexes accord with the requirements of commodity pesticide.PTLC-HPLC analytical method for periplocoside T has been established. For 10% ME, average recovery is 98.6~103.2%, standard deviation 0.0041,variation coefficient 2.15%; For15% EW, average recovery is 96.6~100.1%, standard deviation 0.0037,variation coefficient is 2.05%. Results meet the analysis requirements. The field test of 10% ME and 15% EW controling cabbage caterpillar had been carried out. The efficacy of 10% ME was 80% at diluted 200 times, and 95% at diluted 50 times. The efficacy of 15% EW was 80% at dilution 50 times, and 93% at diluted 100 times; Both have good application value.