Origanum essential oil [Origanum acutidens (Hand.-Mazz.)] showing insecticidal activity and repellency against red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae) adults was analysed by GC-MS. All constituents of the oil were identified, and the main components were carvacrol (67.2%), p-cymene (16.2%), γ-terpinene (5.5%), thymol (4.9%),and linalool(2.1%). In vapor phase fumigant assay, the origanum oil was more effective in closed condition (LD50 = 0.555 mg/cm3) than in open one (LD50 = 0.353 mg/cm3).This result suggests that the toxicity of the oil to red flour beetle is exerted largely by vapor phase. Based on 24-h LD50 values, the toxicity of caryophyllene oxide (0.00018 mg/cm3) was comparable with that of dichlorvos (0.00007mg/cm3) as a positive insecticide. In addition, thymol, camphene, α-pinene, p-cymene, and γ-terpinene gave good insecticidal activity (LD50 = 0.012 - 0.195 mg/cm3). In repellent test using 9 constituents of origanum oil, caryophyllene oxide showed 100% repellent activity at 0.0158 and 0.0032 mg/cm2. These results indicate that the origanum oil and its some components could be potential candidates as a fumigant and repellent for managing T. castaneum adults. Potential molecular target of repellents will be discussed.

The vapor phase repellency and toxicity of Zanthoxylum piperitum pericarp steam distillate (ZP-SD), Z. armatum seed oil (ZA-SO), and their 29 constituents to the adult female stable fly, Stomoxys calcitrans (Diptera: Muscidae), were examined using filter paper fumigation bioassay. Results were compared with those of the currently used repellent: DEET. Both of ZP-SD and ZA-SO exhibited vapor phase repellency and toxicity to female flies at 5 to 40 mg/filter paper (0.23 to 1.82 mg/cm3 air) during a 120-min exposure, whereas DEET exhibited neither repellency nor toxicity to the stable fly. At 5 mg/filter paper, vapor phase of ZP-SD and ZA-SO repelled 50 to 67% and 61 to 51% flies, respectively, to control area during 30 to 120 min. At 40 mg/filter paper, vapor phase of ZP-SD and ZA-SO caused 100% and 81% mortality, respectively, after 120 min of exposure. Among the tested volatile constituents, cuminaldehyde was the strongest repellent and toxic compound to the fly and was four times more toxic than ZP-SD and ZA-SO. Cuminaldehyde vapor phase repelled 62% flies to control area after 30 min at 2.5 mg/filter paper and caused 100% mortality after 120 min at 10 mg/filter paper. Based on the structure-activity relationships, the toxicity and repellency of constituents having aldehyde moiety were better than those of alcohol or ether one. Overall, ZP-SD, ZA-SO, and their bioactive constituents could be useful as potential vapor repellents to control stable fly population.

The repellency to female Stomoxys calcitrans (L.) of 21 essential oils alone or in combination with Calophyllum inophyllum nut oil (tamanu oil) was examined using a skin bioassay. Results were compared with those following treatment with the commonly used repellent DEET (N,N-diethyl-3-methylbenzamide). As judged by the protection time (PT) to first bite at 0.5 mg cm-2, patchouli (3.67 h) was the most effective essential oil, followed by clove bud, lovage root, clove leaf and thyme white essential oils (3.50-2.12 h). Thyme red, oregano and geranium essential oils exhibited moderate protection time (PT, 1.24-1.11 h). At 0.25 mg cm-2, effective protection time of clove bud, clove leaf and lovage root essential oils was about 1 h. The protection times of DEET were 4.47 and 2.17h at 0.5 and 0.25 mg cm-2 respectively. The remarkable increase in the protection time were produced by binary mixtures of five essential oils (clove bud, clove leaf, thyme white, patchouli and savory) and tamanu oil (0.25:2.0 mg cm-2) compared with those of either the constituted essential oil, tamanu oil or DEET alone, indicating the involvement in synergy. These essential oils, tamanu oil and binary mixtures did not cause any adverse effects on the human volunteers at 0.5 mg cm-2 except savory oil. Thus binary mixtures of essential oils and tamanu oil described merit further study as potential insect repellents for protection from humans and domestic animals from biting and nuisance caused by S. calcitrans.

The repellent constituents of essential oils from Zanthoxylum armatum (Rutaceae) seed and Zanthoxylum piperitum fruit against female Stomoxys calcitrans were analyzed by gas chromatography and gas chromatography-mass spectrometry. The repellency of two Zanthoxylum essential oils and 11 oil compounds against female S. calcitrans was examined using a skin bioassay. Results were compared with those of the most widely used repellent DEET. Both Z. armatum seed and Z. piperitum fruit oils provided complete and good protection from fly bites for 30 min at 0.4 and 0.2 mg/cm2, respectively. At 0.05 mg/cm2, both oils gave ca 70 and 40% repellency at 30 and 60 min post-treatment, respectively, whereas DEET provided 83 and 73% protection. Of test compounds, cuminaldehyde at 0.05 mg/cm2 gave 92 and 69% repellency at 10 and 30 min post-treatment, respectively, whereas 1,8-cineole, and citronellal provided approx. 76% repellency at 10 min. The Zanthoxylum oils and their constituents, particularly cuminaldehyde, merit further study as potential insect repellents for the protection from humans and domestic animals from biting and nuisance caused by S. calcitrans.

점박이응애(Tetranychus urticae)에 대한 3종 식물정유(caraway oil, hyssop oil, lime oil)의 기피활성을 조사하였다. 이들 중 caraway oil이 1,000 ppm의 농도에서 의 기피효과를 나타내었으며, GC와 GC-MS로 분석한 결과 carvone과 limonene이 주요한 성분이었다. 따라서 caraway oil의 주요한 화합물에 대한 기피활성을 검정결과 limonene의 1,000과 100 ppm에서 각각 와 의 기피효과를 나타내었다.

점박이응애(Tetranychus urticae)에 대한 34종 terpene의 훈증독성, 접촉독성 및 기피효과를 조사하였다. 훈증독성은 10/1(공기)의 농도에서 isosafrole, safrole이 모두 98.4%의 살비율을 나타내었다. 이 두 화합물의 LD값은 각각 2.6, 4.3/1이었다. 접촉독은 isosafrole만이 알에 대해서 60.2%의 살란활성을 보인 것 외에 대부분의 terpene에서 활성이 낮거나 없었다. 약제감수성 계통에 대한 기피반응을 조사한 결과 hexanoic acid와 limonene이 1,000ppm에서 각각 79.1%와 87.8%의 기피효과를 나타내었다. 한편 fenprothion저항성 계통과 pyridaben저항성계통에 대해서 hexanoic acid는 각각 77.8%과 83.3%의 기피효과를 나타내었다. 그러나 두저항성계통에 대한 limonene(1,000ppm)의 기피효과는 각각 17.8%와 10.0%로서 감수성계통에 대한 기피효과와 상반된 결과를 나타내었다.다.

본 연구는 표고원목재배시 골목을 가해하는 털두꺼비하늘소(Moechotypa diphysis) 성충에 대해서 25종 monoterpenoid의 훈증독성, 접촉독성 및 산란기피효과를 조사하였다. 훈증독성은 20(equation omitted)/954 ml (공기)의 농도에서 1, 8-cineole, fenchone, pulegone, (equation omitted)-terpinene이, 10(equation omitted)/954 ml (공기)의 농도에서는 pulegone과 (equation omitted)-terpinene이, 그리고 5(equation omitted)/954 m1 (공기)의 농도에서는 pulegone만이 100%의 살충률을 나타내었다. 접촉독성은 pulegone만이 70%의 살충률을 보인 것 외에 대부분의 monoterpenoid에서 활성이 낮거나 없었다. 후각계를 이용한 기피반응은 1 (equation omitted)에서 bornylacetate, carvacrol, 1, 8-cineole, menthol은 기피반응을 보였고, 반면 citronellol은 유인반응을 보였다. 실내에서 수행한 산란기피효과는 25개의 monoterpenoid중 1,000ppm의 농도에서 carveol, geraniol, perillyl alcohol이 각각 82.1%, 78.3%, 87.5%의 효과를 보였다. 이 3 화합물을 가지고 야외포장 적용시험을 수행한 결과 10,000ppm과 1,000ppm의 농도에서 3일째까지 geraniol이 가장 효과가 좋았으나 잔효성은 없는 것으로 나타났다.

본 연구에서는 표면 침투 및 코팅형 흡수방지재인 Polydimethylsiloxane(PDMS)을 고인성 섬유복합체(ECC)에 적용하여 적용성, 강도 평가 및 염화물이온 침투 저항성능에 대한 연구를 수행하였다. PDMS 적용 방법에 따른 침투깊이를 분석한 결과 모든 방법에서 KS F4930 의 기준을 만족하는 것을 확인하였다. 적용 방법 중, 침지 방법이 가장 우수한 침투깊이를 보였으나 현장적용성을 고려할 경우 스프레이 방법이 적용 가능한 것으로 확인되었다. ECC 배합에 따른 PDMS 침투깊이 실험 결과 배합강도가 감소할수록 침투깊이는 최대 70% 이상 증가하는 경향을 나타났다. 압축강도 시험 결과에서는 PDMS 침투 깊이가 큰 M4-A, M4-B 시험체의 압축강도는 PDMS를 적용하지 않은 M4 시험체와 비교하여 9.6%, 8.0% 압축강도가 감소하였다. 또한, 침투깊이가 작은 M1-A와 M1-B 시험체의 압축강도는 M1 시험체와 비교하여 4%, 2.2% 감소하여 PDMS 침투깊이가 클수록 강도감소율이 증가하였다. 염소이온침투 저항성능 평가 시험결과, PDMS의 침투깊이가 클수록 염소이온 침투 저항성능이 향상되는 것을 확인하였다.