Components analysis of exocarp and kernel extracts of Ginkgo biloba L. seeds: investigation into the repellent effects against Tetranychus urticae Koch.

Environmental friendly pesticides with a natural origin can be used as an alternative to chemicals in plant pests control programs. From this perspective, the extract of Ginkgo biloba L. plant is important. In this study which was conducted in 2010, the ethereal extract of exocarp and kernel of G. biloba seed was analyzed using a Gas Chromatograph Mass Spectroscope. The components included ginkgolide A, B and C, bilobalide, catechin, compferol, bilobtine, quercetin and isoginkgotine. Ginkgolide A, with an abundance of 28.7 and 18.7 percent in the kernel and exocarp, respectively, was the prevalent metabolitye among the components. Catechin was only observed in the exocarp extract while quercetin was only found in the kernel extract. The repellent effects of extracts on Tetranychus urticae Koch was tested using a Y-tube olfactometer, which is an enclosed bioassay to resolve responses to test and control volatiles. Both extracts showed significant repellency for the pest, and there were no statistical differences between the extracts. The significance of this similarity is the possible utilization of waste products  from drug facilities to produce compounds with repellent effects.