• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.24-29
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• 2001

This study was conducted to investigate insecticidal activities of Ginkgo biloba (L.) leaves-derived bilobalide and its hydrolysis and oxidation products against adults of Nilaparavata lugens Stal. To find out active insecticidal moiety of bilobalide, decomposed intermediates and derivatives of bilobalide were made by hydrolysis, oxidation, and acetylation. The structures of hydrolysis product by base and oxidation product by acid were identified as cyclopentenone analogues and trilactone sesquiterpene from dehydration of bilobalide, respectively. Insecticidal activities of the decomposed intermediates and the derivatives of bilobalide decreased in the order of bilobalide, monoacetate, ginkgolide C, oxidation product, diacetate, and hydrolysis product. Therefore, trilactone structure of bilobalide may be essential for its insecticidal activity.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.239-243
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• 2018

Essential oils of coriander (Coriandrum sativum L.) seeds were extracted by three extraction methods, steam distillation extraction (SDE), hexane extraction (HE) and supercritical extraction (SE), to compare their insecticidal activities against Sitophilus oryzae and S. zeamais. Although the essential oil extracted by HE and SE did not show insecticidal activities, the essential oil extracted by SDE showed the highest insecticidal activities against S. oryzae and S. zeamais. The chemical compositions of the essential oil extracted by SDE were analyzed by GC-MS. The most abundant compounds were linalool (59.92%), camphor (7.94%), linalool oxide (7.70%), p-cymene (7.44%), ${\alpha}-pinene$ (6.44%), limonene (3.29%) and geranyl acetate (3.19%). Camphor and linalool as major constituents showed the highest insecticidal activities against S. oryzae and S. zeamais whereas other constituents did not show insecticidal activities. As a result, the essential oil extracted by SDE, camphor and linalool showed a potential for development as insecticide against the storage pests.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.287-290
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• 2011

Environment friendly agricultural material products (EFAMs) in current market were evaluated for their insecticidal or acaricidal activities. EFAMs were evaluated against Tetranychus urticae, Plutella xylostella, Myzus persicae and Nilaparvata lugens in spray method. Several EFAMs indicated high control value in spray method. Hatchability of T. urticae was relatively high after EFAM treatment. some materials show high insecticidal activities against P. xylostella larvae but not against eggs. Few mete rials showed more than 80% insecticidal activities against M. persicae and N. lugen. The control value of more than half the materials for pest control was lower than 60%. EFAMs containing S. flavescens, neem oil and Rape showed higher control value.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.65-74
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• 2008

Methanol extracts of 35 plant species in 20 families were tested for their insecticidal activities and repellent effects against Nilaparvata lugens female adult by topical application and spray methods. The insecticidal activities and repellent effects of variousplant species and parts were different. The methanol extracts from stem of Garcinia xanthochymus, Senecio scandens and Phytolacca americana, seedcoat of Ginkgo biloba, and leaf+stem of Ailanthus altissima and Catalpa ovata showed potent insecticidal activities against N. lugens. Specially, the G. biloba extract exhibited higher than 90% mortality against N. lugens at a concentration of 4,000 ppm. Repellent effects of plant extracts obtained from whole plant of Daucus carota, fruit of Semecarpus anacardium, leaf+stem of C. ovata and Wisteria sinensis were active, and potent. Also, the plant extracts that are potent in insecticidal activity not necessarily have high repellent activity showing no significant corelation between the two activities.

• The Korean Journal of Pesticide Science
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• v.11 no.1
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• pp.52-58
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• 2007

ALA (5-aminolevulinic acid) has been proposed as a tetrapyrrole-dependent photodynamic herbicide and insecticide by the action of the protoporphyrinogen IX oxidase (Protox IX). The present study was conducted to determine growth responses of plant and insects to ALA, biodegradable biopesticidal substance. In the paddy condition experiment, plant height and shoot fresh weight of barnyardgrass (Echinochloa crus-galli) was more reduced by ALA than rice plants, even though both plant species show great phytotoxicity. Hairy crabgrass (Digitaria sanguinalis), a monocot weed, was more sensitive to ALA at 5mM under upland condition when ALA applied on the foliage, compared with soybean (Glycine max) as a dicot crop. ALA solutions were tested for their insecticidal and larvicidal activities against Spodaptera exigua (Hubner) and Tetranychus urticae Koch. by foliar application and leaf-dipping method. The result showed higher insecticidal activity of ALA at 10mM and its mixture with insecticide luferon against S. exigua. Strongest insecticidal activity against T. urticae was observed from the ALA solution at 10mM 72 days after application. This results show that ALA solution had potent herbicidal and insecticidal activities against agricultural pests even though their activities were lower than those of synthetic pesticides.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1073-1076
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• 2014

In attempt to lead compounds exhibiting both insecticidal and fungicidal activities, a series of O-benzyl oximeether derivatives were designed and synthesized by introducing ${\beta}$-methoxyacrylate pharmacophore into a scaffold. The insecticidal activity against Aphis fabae and the fungicidal activity against Erysiphe graminis were screened. The title compounds exhibited remarkable insecticidal and fungicidal activities. The most potent compound 6d was identified. Its insecticidal $LC_{50}$ against A. fabae is 6.4 mg/L, which is lower than that of chlorfenapyr (19.4 mg/L) and even close to the level of imidacloprid (4.8 mg/L). Its fungicidal $EC_{90}$ in preventive and curative treatment against E. graminis are 2.2 and 4.8 mg/L, respectively, which are lower than azoxystrobin (7.0 and 5.9 mg/L). These results indicate that compound 6d can be considered as a lead for further developing new O-benzyl oxime-ether typed candidates with both fungicidal and insecticidal activities.

• Korean Journal of Agricultural Science
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• v.41 no.3
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• pp.177-185
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• 2014

Aspiring to the new raw materials of insecticides is one of the plant extracts. The material structure of a variety of plant extracts have because the material to the defense of the plant itself, the case of insecticides, using plant extracts, safe, has low toxicity and has the advantage of highly distinctive and fall. Coltsfoot (Tussilago farfara L.) is belonging to the family Compositae, and distributed in all parts of China as medicinal plants and indigenous plants used. Coltsfoot is known that it is effect to respiratory disease and has an antiviral effect. However, the reported insecticidal activity of coltsfoot could be not found. Fortunately, I found insecticidal activities when I was screening the bioassay against several insects with a lot of plant extracts. Using the ethanol extract of the Tussilago farfara, there were insecticidal activities against Culex pipiens pallens and Tetranychus urticae. There were several fractions in ethanol extract of coltsfoot by using various organic solvents. Hexane fraction showed a higher insecticidal activity than any other fraction. It is confirmed that hexane fraction contained pyrethrin by using HPLC analysis. So, it might be suggested that extract of coltsfoot has an insecticidal activity and its effect due to a ingredient of pyrethrin.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.624-633
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• 2014

This study separated the crude extract (70% ethanol) of and its three fractions (hexane, chloroform and ethyl acetate extracts) on the basis of polarity indexes, and examined for their insecticidal activities against aphid (Uroleucon lactucicola). For crude extraction, the 70% ethanol extract showed the best extract yield (58.0%) and insecticidal activity (69.0%) among the various concentrations tested (water, 30% ethanol, 50% ethanol, 70% ethanol and 95% ethanol). The major chemical compounds of different fractions (hexane, chloroform and ethyl acetate extracts) were identified as eugenol by head space-GC-MS analysis. The hexane extract showed the highest eugenol content (43.7%) and insecticidal activity (80.0%). The insecticidal activity is accordingly believed to be attributable to the eugenol component. This may provide a useful starting point for the development of bio-pesticides.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.87-96
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• 2011

To study solar activated insecticide, three types of dihydroxyl phosphorus(V) triazatetrabenzocorrole derivatives ($P(OH)_2TBCs$) including H, 4'-methoxy phenoxy, 4'-tert butyl phenoxy substituents were synthesized. The results show that slightly red-shift with introducing substituents was observed and singlet oxygen was generated by the sunlight. Based on photochemical properties, solar activated insecticidal activity tests against Liriomyza trifolii (Burgess) were carried out. Overall insecticidal activities were 100~85.7% in the concentration of 500ppm, and especially in the case of compound $P(OH)_2TBC$ the insecticidal activities was 100%.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.492-497
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• 1994

Extracts of 43 species of plants were tested for their insecticidal and acaricidal activities against six species of insect pests and one mite species. The methanol extract of Ginkgo biloba leaves selectively was found to have potent insecticidal activity against Nilaparvata lugens (Stal), whereas steam distillate of Thujopsis dolabarata var. hondai sawdust showed potent insecticidal activities with a broad spectrum. The methanol extract of Pinus densiflora leaves and steam distillate of T. dolabrata var. hondai sawdust exhibited potent activities against Tetranychus urticae (Koch).