Study on the Extraction of Active Ingredients from Walnut Leaves and Their Mosquito Repellent Activities
In order to screen walnut leaf extracts with strong potency and mosquito repellent effects,ultrasound-assisted hydrodistillation was applied to extract'J.regia Wen185''C.cathayensis''J.nigra'and'J.regia Shisheng'leaf volatile oil.With the extraction rate of volatile oil from walnut leaves as the index,orthogonal experiments were conducted on the basis of single-factor experiments to derive the best extraction conditions of volatile oil from walnut leaves,and combined with the mosquito repellent test,the best repellent content of 4 walnut leaf extracts were screened with the repellent rate as the index.It was shown that the best extraction conditions for the extraction of volatile oil from'J.nigra'leaves by ultrasound-assisted water distillation were 8 h,10 min of ultrasound time,and 1:10(g·mL-1)solid-liquid ratio.Under these conditions,the extraction rate of volatile oil of walnut leaves was 0.475％.Using anhydrous ethanol as the solvent,the mosquito repellent rate of the solutions of four kinds of walnut leaf volatile oil extract solutions were measured under dilution of 10％,20％,30％and 40％.The mosquito repellent effect time of'J.nigra'leaf volatile oil extract solution could reach 20 min at 30％content,and when the repellent rate was 85.18％,the repellent effect was the best.Vaporized oil extract solution of'J.nigra'leaves had good mosquito repellent effect and had the potential to be developed as a plant-derived repellent,which was worthy of further promotion and application.
walnut leavesoptimal extraction conditionsactive ingredientsrepellent effect on mosquito
国家科技期刊平台
NSTL
万方数据
