• Journal of the Korean Wood Science and Technology
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• 제45권6호
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• pp.720-727
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• 2017

Antioxidants are known to affect the feeding habits of termites and a good source is pine bark which contains high levels of antioxidants which can be extracted with neutral solvents. In this study procyanidins (PCs)-rich MeOH-extract and a hot-water extract (HWE) were prepared from Pinus radiata bark. HWE was further separated into crude PCs (CPCs), polymeric PCs (PPCs), and low-molecular-weight PCs (LMWPCs) fractions. The MeOH extract and these fractions were examined for termite (Reticulitermes flavipes Kollar) antifeedant activities using a no-choice test. Catechin was used as a positive control. The LMWPCs was found to be the most effective deterrent to termite feeding. The comparative efficiency of the compounds tested were LMWPCs > PPCs > CPCs > MeOH extract, with the latter being more dependent on molecular weight than on its antioxidant activity.

• Molecules and Cells
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• 제39권4호
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• pp.310-315
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• 2016

Coumarin is a phenolic compound that mainly affects the liver due to its metabolization into a toxic compound. The deterrent and ovicidal activities of coumarin in insect models such as Drosophila melanogaster have been reported. Here we explore the molecular mechanisms by which these insects protect themselves and their eggs from this toxic plant metabolite. Coumarin was fatal to the flies in a dosage-dependent manner. However, coumarin feeding could be inhibited through activation of the aversive gustatory receptor neurons (GRNs), but not the olfactory receptor neurons. Furthermore, three gustatory receptors, GR33a, GR66a, and GR93a, functioned together in coumarin detection by the proboscis. However, GR33a, but not GR66a and GR93a, was required to avoid coumarin during oviposition, with a choice of the same substrates provided as in binary food choice assay. Taken together, these findings suggest that anti-feeding activity and oviposition to avoid coumarin occur via separate mechanisms.

• 한국응용곤충학회지
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• 제28권3호
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• pp.113-119
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• 1989

금잔화, 들깨풀, 수국등 10종의 야생식물잎의 추출물이 담배나방(Heliothis assulta) 유충의 발육과 성충의 산란에 미치는 영향을 조사하였다. 그 결과 유충이 높았으며 대부분 1영과 2영 기간중 먹지않기 때문이다. 여기서 살아남은 유충들도 발육기간 및 탈피횟수는 증가하는 경향을 보였다. 이중 갈매나무와 때죽나무의 추출물은 성충의 산란도 상당히 억제하였다.