Extraction Analysis And Study On The Repellent Effect Of The Active Components In Four Species Of Plants Repellents

It is of great value to develop and use safe botanical repellents because of its advantages of small side-effects and less chance to produce pest resistance. In this experiment, with four plants of Mongolia Artemisia,tomatoes, Pelargonium vanilla and Pelargonium graveolens, human repellent test is used for studying therepellent effect of extract and the relationship of concentrations of ethanol tincture of ingredients and repellenteffect. The results are as follows:1. With respectively95%ethanol, acetone, toluene and petroleum, ultrasonic extraction method was usedto extract the selected plants in order to confirm the optimum extraction agent. The results showed that: thebest extraction agent of Mongolian Artemisia, the tomatoes and Pelargonium was95%ethanol, the extractionrates were12.50%,11.80%and10.60%respectively; the best extraction solvent of Pelargonium vanilla wasacetone, the extraction rate was10.80%.2. The results of human repellent effect test of crude extract showed that: the repellent effect ofMongolian Artemisia extract was the best, the time of effective protection was up to120minutes and theeffective protection rate was84.21%.3. Column chromatography was used to separate the crude extract, and the results showed the elutedfraction of Mongolian Artemisia, tomatoes and Pelargonium crude mainly existed in the eluent of petroleum,with the rate of ether: ethanol=5:3and petroleum ether: ethanol=5:5.4. The results of repellent effect test of the eluting component indicate the repellent effect ofconcentration of Mongolian Artemisia crude extract fraction with the fate of petroleum ether: ethanol=5:3elution was the best, the effective protection time was120minutes and the effective protection rate was83.11%.5. The eluent effective ingredient of Mongolian Artemisia, tomato and Pelargonium crude was confirmedby GC-MS. The results showed the three plants eluent all contained C10H16, which showed that the substancemay be effective repellent composition.6. The results of sifting of repellent effect of preparations showed that: the crude extract of MongolianArtemisia got with eluent of petroleum ether: ethanol=5:3, and the crude extract of Tomato fraction got withthe eluent of petroleum ether: ethanol=5:5, respectively combined with Wind medicated oil with the volumeratio=1:1, and combined the mixtures with Wind medicated oil with the volume ratio=1:1:1, to make the7%concentration and15%concentration of ethanol tincture, the repellent effect was the best in2hours.7. Compared with the effect of chemical insect repellent, the results of the test showed that: the crudeextract of Mongolian Artemisia got with eluent of petroleum ether: ethanol=5:3, and the crude extract ofTomato fraction got with the eluent of petroleum ether: ethanol=5:5, respectively combined with Windmedicated oil with the volume ratio=1:1, and combined the mixtures with Wind medicated oil with the volumeratio=1:1:1, to make the15%concentration of ethanol tincture, the effect were as same as the of chemicalinsect repellent, and the effective protection rates were83.00%,80.00%and85.00%respectively in8hours.