Insecticidal Effect of Dermatoohagoides pteronyssinus using Ginkgo biloba Leaves Extracts

A Insecticidal effect of Ginkgo biloba leaves extract was conducted for Dermatophagoides pteronyssinus as a predominant species in korea. D. pteronyssinus has been cultured in constant temperature and humidity chamber at the 25$^{\circ}C$ and 75% of relative humidity. The mortality of mites was determined by counting the dead bodies for every hour within 48 hours with pin hall microscope after treated by Ginkgo biloba leaves extract spreaded on 0.1 g of mass cultured media. The sequence of mortality for D. pteronyssinus are as follows, bilobalide was 91.6%, 80$^{\circ}C$ water extract was 82.8%, second water fraction was 75%, ethyl acetate fraction from 80$^{\circ}C$ water fraction was 73%, first ethyl acetate fraction from 80$^{\circ}C$ water extract was 69.4%, putaltrin was 65%, distilled water was 58%, methanol extract was 57.8%, Ginkgolide-A was 57.1 %, ethyl acetate fraction of 80$^{\circ}C$ water extract was 55%, respectively. From the these results we conclude that the bilobalide is the most effective component in the Ginkgo biloba leaves extract having insecticidal effect on house dust mite.

은행잎 추출물의 집먼지 진드기 Dermatophagoides pteronyssinus에 대한 살충효과

본 연구에서는 은행잎에 존재하는 생리활성 물질이 추출용매와 추출조건에 따른 D. pteronyssinus에 대한 살충 실험을 통해 최적 추출 조건을 확립하였다. 은행잎 성분 중 bilobalide가 D. pteronyssinus에 살충효과가 있음을 검증하였으며, 다양한 은행잎 추출조건에 따른 살충실험을 한 결과 48시간 이후 약 68%$\sim$80%의 치사율을 보였다. 종합적으로 판단해 볼 때 경제성과 치사율을 고려하면 80$^{\circ}C$에서 온수추출물 (GLW80)이 가장 최적추출 조건이다.