• 한국응용곤충학회지
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• 제51권2호
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• pp.149-152
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• 2012

잎침지법을 이용하여 후추 열매 메탄올 추출물 및 분리된 화합물들의 배추좀나방(Plutellaxylostella) 유충에 대한 살충 활성을 검정하였다. 후추 열매 메탄올 추출물은 배추좀나방 유충에 대해 5.0과 2.5 mg/mL 농도에서 각각 100%와 97%의 살충 활성을 보였다. 후추 열매에서 유래된 화합물들의 배추좀나방에 대한 살충 활성을 조사한 결과, guineensine ($LC_{50}$=0.013 mg/mL)의 살충 활성이 가장 높았으며, 다음으로 retrofractamide A (0.020 mg/mL), pipercide (0.033 mg/mL) 그리고 pellitorine (0.046 mg/mL) 순이었다. Piperine의 반수치사농도는 0.5 mg/mL 이상이었다.

• BMB Reports
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• 제34권5호
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• pp.402-407
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• 2001

Based on the currently proposed toxicity model for the different Bacillus thuringiensis Cry $\delta$-endotoxins, their pore-forming activity involves the insertion of the ${\alpha}4-{\alpha}5$ helical hairpin into the membrane of the target midgut epithelial cell. In this study, a number of polar or charged residues in helix 4 within domain I of the 65-kDa dipteranactive Cry11A toxin, Lys-123, Tyr-125, Asn-128, Ser-130, Gln-135, Arg-136, Gln-139 and Glu-141, were initially substituted with alanine by using PCR-based directed mutagenesis. All mutant toxins were expressed as cytoplasmic inclusions in Escherichia coli upon induction with IPTG. Similar to the wild-type protoxin inclusion, the solubility of each mutant inclusion in the carbonate buffer, pH 9.0, was relatively low When E. coli cells, expressing each of the mutant proteins, were tested for toxicity against Aedes aegypti mosquito-larvae, toxicity was completely abolished for the alanine substitution of arginine at position 136. However, mutations at the other positions still retained a high level of larvicidal activity Interestingly, further analysis of this critical arginine residue by specific mutagenesis showed that conversions of arginine-136 to aspartate, glutamine, or even to the most conserved residue lysine, also abolished the wild-type activity The results of this study revealed an important determinant in toxin function for the positively charged side chain of arginine-136 in helix 4 of the Cry11A toxin.

• International Journal of Industrial Entomology and Biomaterials
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• 제21권1호
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• pp.133-137
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• 2010

The perilla leaf pyralid moth, Pyrausta panopealis Walker (Lepidoptera: Pyralidae), is a serious pest damaging to leaf perilla. In order to establish the life parameters of P. panopealis for eventual purpose of control, the developmental span of each stage was investigated under five temperature regimes ($20^{\circ}C{\sim}30^{\circ}C$). The larval period of P. panopealis was longest as 26.8 days at $20^{\circ}C$ and shortened as temperature goes up to $30^{\circ}C$ as 11.3 days. Survivorship of the larval P. panopealis was the highest at $27.5^{\circ}C$ as 82.5%, whereas that of other temperatures ranged from 40% ($20^{\circ}C$) to 60.0% ($30^{\circ}C$), indicating that the P. panopealis appears to favor somewhat higher temperature. In addition to larval period, the duration of egg, prepupal, and pupal period also were shortened sharply as temperature goes up, whereas the duration of adult stage shortened a maximum of only two days as temperature goes up. After the perilla leaf pyralid moths were successfully stabilized in indoor environment the larvicidal efficacy of ten on-the-market environmentfriendly agricultural materials (EFAMs) that were previously selected from the result of other moth species was tested. Seven of the ten tested showed more than 90% of mortality within 12 hrs and reached nearly up to 100% within 24 hrs, but the remaining three showed less than ~70%.

• 한국어병학회지
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• 제13권2호
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• pp.137-142
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• 2000

간흡충 탈낭유충에 대한 잉어, 붕어, 참붕어의 보체 살충능 및 식세포 chemiluminescent 반응 차이를 조사하였다. 낙동강에서 채집한 참붕어는 모두 간흡충 피낭유충에 중감염되어 있었으나, 진영의 저수지에서 채집한 참붕어 및 낙동강에서 채집한 붕어와 양식 잉어에서는 간흡충 피낭유충이 전혀 검출되지 않았다. 각 실험어의 신선혈청을 이용하여 간흡충 탈낭유충에 대한 살충능을 조사한 결과 간흡충 피낭유충에 중감염된 참붕어 혈청과 붕어의 혈청은 잉어의 혈청에 비해 높은 살충능을 나타낸 반면, 간흡충 피낭유충에 감염되지 않은 참붕어의 혈청은 가장 낮은 살충능을 나타냈다. 각 어종의 혈청을 $47^{\circ}C$에서 30분간 처리하여 보체를 불활화시킨 결과 모든 실험어종에서 혈청의 살충능이 완전히 사라졌다. 간흡충 탈낭유충 균질액의 상층액을 각 어종의 두신 식세포에 첨가하여 chemiluminescent(CL) 반응을 측정한 결과 참붕어와 잉어에서 CL반응이 zymosan만을 첨가했을때에 비해 유의적(P<0.05)으로 감소하였으며, 각 어종별 간흡충 탈낭유충 균질액의 상충액 첨가에 의한 CL반응 감소율은 참붕어의 경우 22.9%, 붕어 9.6%,잉어 12.4%로 나타났다.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2001년도 합동 춘계 학술발표회
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• pp.72-72
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• 2001

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2001년도 추계 합동 심포지엄 및 학술발표대회
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• pp.149-149
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• 2001

• BMB Reports
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• 제44권10호
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• pp.674-679
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• 2011

Bacillus sphaericus produces mosquito-larvicidal binary toxin composed of BinA and BinB. While BinB is expected to bind to a specific receptor on the cell membrane, BinA interacts to BinB or BinB receptor complex and translocates into the cytosol to exert its activity via unknown mechanism. To investigate functional roles of aromatic cluster in BinA, amino acids at positions Y213, Y214, Y215, W222 and W226 were substituted by leucine. All mutant proteins were highly produced and their secondary structures were not affected by these substitutions. All mutants are able to insert into lipid monolayers as observed by Langmuir-Blodgett trough and could permeabilize the liposomes in a similar manner as the wild type. However, mosquito-larvicidal activity was abolished for W222L and W226L mutants suggesting that tryptophan residues at both positions play an important role in the toxicity of BinA, possibly involved in the cytopathological process after toxin entry into the cells.

• 한국응용곤충학회지
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• 제33권4호
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• pp.225-229
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• 1994

배추좀나방과 담배거세미나방 유충에 대한 30종 한방 식물체 메탄올 조추출몰의 살충활성 및 섭식 저해활성을 잎침지법을 이용하여 5,000ppm으로 검정하였다. 황련의 추출물은배추좀나방에 대해 살충작용을 보였다. 길경, 사삼, 세신, 오배자 및 자초의 추출물은 배추좀나방 유충에 대해, 목통 및 속새의 추출물은 담배거세미나방 유충에 대한 강한 섭식저해활성을 보였으나, 오배자와 황련의 추출물은 이들 나비목 유충 모두에 강한 섭식저해활성을 나타내었다.

• Journal of the Korean Wood Science and Technology
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• 제44권4호
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• pp.494-504
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• 2016

Eucalyptus oils are widely used as spices, perfume industrial materials, food flavorings, and medicines. Several types of Eucalyptus oils also have insecticidal activity and as carminative. This study investigated the chemical composition, insecticidal (larvicidal and repellent) activity of E. urophylla oil against filarial mosquito Culex quinquefasciatus. E. urophylla oil was obtained from fresh leaves by water-steam distillation with oil yield 1.08%. E. urophylla oil in this study had no color (clear), has odor (typical eucalyptus), with specific gravity 0.941; refractive index 1.465; miscibility in 70% ethanol 1 : 3; and optical rotation (-) $5.83^{\circ}$. The major compounds of the oil were ${\alpha}$-pinene (11.73%), 1,8-cineole (49.86%), ${\beta}$-ocimene (6.25%), ${\gamma}$-terpinene (9.11%), and ${\alpha}$-terpinyl acetate (7.63%). The result showed the excellent insecticide activity against C. quinquefasciatus. The oil provided larvicidal activity with $LC_{50}$: 80.21 ppm and $LC_{90}$: 210.18 ppm, and repellent activity with $IC_{50}$: 0.82% and $IC_{90}$: 4.88%. The present study showed the effectiveness of E. urophylla as natural insecticide against C. quinquefasciatus, the mosquito vector of filariasis.

• BMB Reports
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• 제41권11호
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• pp.820-825
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• 2008

Bacillus thuringiensis Cyt2Aa toxin is a mosquito-larvicidal and cytolytic $\delta$-endotoxin, which is synthesized as a protoxin and forms crystalline inclusions within the cell. These inclusions are solubilized under alkaline conditions and are activated by proteases within the larval gut. In order to assess the functions of the N-and C-terminal regions of the protoxin, several N- and C-terminal truncated forms of Cyt2Aa were constructed. It was determined that amino acid removal at the N-terminal, which disrupts the $\beta$1 structure, might critically influence toxin production and inclusion formation. The deletion of 22 amino acids from the C-terminus reduced the production and solubility of the toxin. However, the removal of more than 22 amino acids from the C-terminus or the addition of a bulky group to this region could result in the inability of the protein to adopt the proper folding. These findings directly demonstrated the critical roles of N- and C-terminal amino acids on the production and folding of the B. thuringiensis cytolytic $\delta$-endotoxin.