Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were 77.0±4.3% and 81.5±1.3% at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group (67.8±4.3%) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.

To determine their acute toxicities on the earthworm (Eisenia fetida), six toxic chemicals were evaluated, according to the OECD guideline 207: sulfuric acid, methanol, methylethylketone, nitric acid, formic acid, and toluene. Sulfuric acid exhibited the maximum toxicity. The LC50 values of sulfuric acid, nitric acid, formic acid, and toluene were 20.5, 49.1, 55.5, and 534.5 μg cm-2, respectively. Toluene showed 26-fold lower toxicity than sulfuric acid. In this study, methanol and methylethylketone did not exhibit any toxicity to the earthworm. Further evaluation revealed that nitric acid, formic acid, and toluene exerted a change in the body weight of the chemically treated earthworms, whereas the other chemicals were ineffective. These results can be used for environmental risk assessment, when the chemicals are accidently discharged into the environment.

The effects of some essential oils and Sopophora extract on Frankliniella occidentalis adults, Myzus persicae adults, Plutella xylostella larvae, and Spodoptera exigua larvae were investigated. Insecticidal and phytotoxicity activities of emulsion in water formulations containing the active essential oils as active ingredients under laboratory and pot conditions were also tested. Based on these results, NRS-13 and NRS-24 formulations were selected to further assess as follows; the GC and GC-MS analysis on the active essential oils, the quantity analysis of the major components contained in the formulations, their insecticidal activities under pot and field conditions, and their oral, dermal, skin and eye irritation, and fish toxicities. Thus, the NRS-13 (BaechooSaferTM) and NRS-24 (JindiOutTM) formulations could be considered as insecticides for pest control.

Essential oils (EOs) extracted from plants possess various biological activities and have been considered as natural insecticides due to their potent insecticidal activities. In regard to develop natural insecticides, EOs are formulated as an emulsifiable concentrate and their acute toxicity against to fishes were determined in a static condition using Cyprinus carpio. Coriander EO was used as an active ingredient mixed with ethanol for solvent and various surface active agents. The tested EOs were obtained from a commercial market, and three different extractions were also undertaken to produce EO using steam distillation, solvent extraction, and supercritical fluid extraction. Among the emulsifiable concentrate including a commercial coriander EO, surface active agents such as Tween 80, sodium dodecyl benzene sulfonate (SDBS), and mixture of SDBS and Nonidet showed acute toxicity to the fish. With the three different EO extraction, coriander EO obtained from supercritical fluids with Triton X-100 exhibited acute toxicity to C. carpio. Taken together, Tetgitol and Nondet are considered as surface active agents for the emulsifiable formulation of coriander EO.

Toxicity assessment of heavy metals (As, Cr and Pb) has been investigated by using the rate of survival and population growth(r) of marine rotifer, Brachionus plicatilis. The survival rate was determined after 24 hours of exposure to As, Cr and Pb. As and Cr reduced survival rate in dose-dependent manner and a significant reduction were occurred at concentration of greater than 30 and 150 mg L-1, but Pb had no effect on survival rate. The r was determined after 72 hours of exposure to As, Cr and Pb. As, Cr and Pb reduced r in dose-dependent manner and a significant reduction were occurred at concentration of greater than 5, 25 and 50 mg L-1. The toxicity of heavy metals were ranked As>Cr>Pb, with EC50 values of 12.98, 82.34 and 110.14 mg L-1, respectively. The no-observed-effect-concentration (NOEC) of r in As, Cr and Pb exposure were 1, 12.5 and 50 mg L-1, respectively. The lowest-observed-effect-concentration (LOEC) of r in As, Cr and Pb exposure were 5, 25, and 50 mg L-1, respectively. From the results, the concentration of As, Cr and Pb (greater than 5, 25 and 50 mg L-1, respectively) have toxic effect on the r of B. plicatilis in natural ecosystems. These results (including NOEC and EC50) might be useful for the mixing toxicity assessment and toxic guide line of heavy metals in marine ecosystems.

For several decades, lactic acid bacterium (Lactobacillus graminis: LAB) has been generally recognized as safe. To develop the pan-environmental bio-control agent, algicidal activity of the live LAB cell and its culture filtrate (CF) was examined against Microcystis aeruginosa. LAB cells perfectly lysed M. aeruginosa within 3 days, while the CF had a less effect than the live cells, approximately 78% inhibition of algal growth during a same culture period. The concentration of microcystin in alone culture of M. aeruginosa was 7.1 μg L-1, but gradually increased and leach 158.5 μg L-1 on 10 days. However, LAB cells clearly decreased the microcystin by 10.3 μg L-1 in the same period, approximately 93.5%. CF of LAB showed a strong algicidal activity over 75% between pH 2-7, 91.3% by the treatment of proteinase K, 87.8% by below 3 kDa in particle size, and 75.3% by heat treatment, respectively. Of five solvents, fractions of CF passed through solvents diethyl ether and ethyl acetate showed an obvious algicidal activity in the algal-lawn test. Among 5 fractions purified by silica-gel TLC plate, two spots showed a most strong removal activity on M. aeruginosa. Another analysis of GC indicate that CF contained six representative fatty acids. Even though most of these substance have been known as an anti-algal substance against M. aeruginosa, oleic acid is the most effective. These results suggested that the culture filtrate or specific substances, like a fatty acids, in comparison with live L. graminis can be a successful and eco-friendly agent to control Microcystis bloom.

국내에 서식하는 두꺼비의 배아를 이용하여 화학물질의 독성평가에 대한 가능성을 파악하기 위해 FETAX(Frog Embryo Teratogenesis Assay-Xenopus) 기법에 따라 두꺼비(Bufo gargarizans)의 배아를 배양하면서 Zn과 Benomyl의 효과를 probit 분석법으로 조사하였다. 그 결과, Zn과 Benomyl의 농도에 의존하여 유생의 체장 길이는 감소하고 치사율 과 기형율은 증가하였으며 Zn과 Benomyl의 teratogenic concentration(EC50)은 각각 2.3, 1.0㎎/ℓ을 나타내었고 embryo lethal concentrations(LC50)은 10.3, 6.9㎎/ℓ을 나타내었다. Teratogenic index(TI=LC50/EC50)는 Zn의 경우 4.4, Benomyl의 경우 6.7을 나타내어 Zn과 Benomyl은 두꺼비 배아 발달에 최기형성 물질로 작용함을 알 수 있었다. 이상의 결과들로 보아 Zn과 Benomyl 모두 낮은 농도에서 두꺼비 배아발달에 민감하게 반응하였다. 이는 다량의 배아 확보가 가능하며 배양이 용이하고 치사율, 기형율, 성장률, 기형양상 등을 기존의 연구들과 비교하였을 때 유사한 결과를 나타내어 두꺼비 배아를 활용한 시험기법은 화학물질 및 환경오염물질의 독성검정에 활용할 수 있을 것으로 판단된다.

전 세계적으로 원자력 발전소는 442기가 가동 중이며, 62기가 충원될 예정이다. 원자력 발전소의 증가에 따라 방사성 폐기물 유출에 대한 위험성도 증가하였다. 이러한 이유 때문 에, 방사성 폐기물의 처리는 인간, 동물, 식물을 포함하는 자 연 생태계를 보전하는 관점에서 중요하다. 또한, 방사성 폐 기물 유출은 그 지역뿐만 아니라 전 세계적으로 심각한 문 제를 야기한다. 본 연구는 입체 배양세포에 방사성 핵종원 소 (세슘, 스트론튬, 코발트)를 처리하였고 이에 대한 영향력 을 확인하였다. 입체 배양 구조체는 아가로오스 하이드로겔 을 이용하여 제작했으며 암세포 및 정상세포 (HeLa, HepG2, COS-7)를 사용하여 입체 배양을 실시 하였다. 입체 형태로 세포를 배양한 후 세슘, 스트론튬, 코발트 농도 변화에 따라 세포 생존능력을 분석하였다. 이때 입체 배양세포에서 생존 능력이 단층 배양세포 보다 최대 42% 우수한 것을 확인하였 다. 입체 배양구조체는 세포가 형태 및 생리학적으로 in vivo 환경인 조직과 비슷하게 배양을 가능하게 하였다. 따라서, 입체 배양구조체는 기존의 단층 배양 한계점인 in vivo 환경 에 적용시킬 수 없다는 한계를 극복하였다. 본 입체 배양 기 술이 중금속 독성평가 및 단시간 내에 다수의 물질 분석을 수행하는 고속 대량 스크리닝 기술에 활용될 것으로 기대한 다.

This study tested a hypothesis that the bacterial immunosuppresants enhance BtI susceptibility of two mosquitoes, the forest mosquito (Aedes albopictus) and the house mosquito (Culex pipiens pallens). Three symbiotic bacteria Xenorhabdus nematophila (Xn), X. hominickii (Xh), and Photorhabdus temperata subsp. temperata (Ptt) were isolated from their symbiotic nematodes and cultured in nutrient broth to allow them to produce the secondary metabolites. BtI gave significant toxicities to A. albopictus and C. pipiens pallens larvae: 50% of lethal concentration to be 2.9 × 105 spores/mL and 2.2 × 105 spores/mL at 16 h after treatment, respectively. Addition of each bacteria-cultured broth significantly enhanced BtI toxicity to the mosquito larvae by lowering LC50 values of BtI to A. albopictus larvae (1.5 × 105 to Xn, 1.7 × 105 to Xh, and 1.9 × 105 to Ptt, respectively) and to C. pipiens pallens larvae (1.2 × 105 to Xn, 1.3 × 105 to Xh, and 1.5 × 105 to Ptt, respectively). Based on these results, we developed a new mosquitocidal Bt formulation called ‘Dip-Kill’, which consisted of 80% Xn-cultured broth, 10% BtI (1010 spores/mL), and 10% preservative. Only 400 ppm of Dip-Kill showed 100% mortality to fourth instar larvae of A. albopictus and C. pipiens pallens 16 h after treatment.

Oriental fruit moth Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is an important pest for stone fruits like apple, peach, pear etc. Growers usually depend on chemical insecticides to control this pest, but it causes problems like resistance, pest resurgence, and health hazard. Although various plant extracts have been known to be potential against other lepidopterans, their effectiveness against oriental fruit moth has rarely been studied. So, we evaluated toxicity of 28 methanolic plant extracts known from previous literatures in the laboratory condition. Residual toxicity against 1st instar larvae (<5 h old) were examined using glass scintillation vial method at the concentration of 2 mg/ml. Among the tested botanicals Nicotiana tabacum L. was most effective and showed 92% mortality within 20 h and LT50 value was 12.9 h followed by Allium sativum L., Zanthoxylum piperitum (L.), and Sapindus mukorossi Gaerten. which showed 88, 70, and 65% mortality within 20 h, respectively. Rhododendron micranthum Turcz., Humulus japonicus Seibold & Zucc., Nerium indicum Mill., and other extracts showed least effectiveness on 1st instar larvae of oriental fruit moth. Hence, we suggest N. tabacum, A. sativum, Z. piperitum, and S, mukorossi as botanicals to be used against oriental fruit moth.

Arsenic is an environmental pollutant and is known to induce toxicity. Arsenic acts on cells through a variety of mechanisms, influencing numerous signal transduction pathways. It induces a variety of cellular effects such as apoptosis, growth inhibition, promotion or inhibition of differentiation and angiogenesis. Arsenic has been associated with cancers of the skin, bladder, lung, kidney, and liver as well as with noncancerous conditions, diabetes and hepatopathy. However, arsenic trioxide (ATO) was reported to induce remission in patients with acute promyelocytic leukemia (APL). The anticancer efficiency of ATO was not restricted to APL; however, it has been extended to many solid tumors, including liver, cervical, prostate, lung, esophagus, and bladder tumors. Therefore, in this study, a number of previous studies are summarized that demonstrate arsenic-induced toxicity, including carcinogenesis and anticancer activity in vitro and in vivo. The arsenic metabolism that is involved in arsenic-induced toxicity is also discussed.

The attachment of 2-aminobenzamide to carboxylated multi-wall carbon nanotubes (MWCNTs)- COOH was achieved through the formation of amide bonds. Then, the functionalized MWCNTs, MWCNT-amide, were treated by phosphoryl chloride to produce MWCNT-quin. The products were characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, thermogravimetric analysis, derivative thermogravimetric, steady-state fluorescence spectroscopy, and solubility testing. MWCNT-quin showed photo-electronic properties, which is due to the attachment of the 4-hydroxyquinazoline groups to them as proved by steady-state fluorescence spectroscopy. This suggests intramolecular interactions between the tubes and the attached 4-hydroxyquinazoline. The toxicity of the samples was evaluated in human embryonic kidney HEK293 and human breast cancer SKBR3 cell lines, and the viable cell numbers were measured by 3-(4,5-dimethyl- 2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) after the cells were cultured for 24 h. Cellular investigations showed that the modified MWCNTs, particularly MWCNT- quin, have considerably significant toxic impact on SKBR3 as compared to HEK293 at the concentration of 5 μg/mL.

This study was conducted to determine the toxicity to adult Myzus persicae (Sulzer) and Aphis gossypii Glover of 88 plant essential oils and six experimental spray formulations containing bitter orange or marjoram oil was examined using the vapor-phase mortality and spray bioassays. Results were compared with those of two conventional insecticides deltamethrin and dichlorvos. As judged by 24 h LC50 values, bitter orange oil (0.0212 and 0.0192 mg/cm3) was the most active material, followed by marjoram, celeryseed, and cypress oils (0.0239-0.0508 and 0.0209-0.0542 mg/cm3). These essential oils were significantly less toxic than dichlorvos, respectively. These essential oils were consistently more toxic to adult M. persicae in closed versus open containers, indicating that toxicity was achieved mainly through the action of vapor. Bitter orange oil and marjoram oil applied as 1% spray provided complete mortality toward two aphid species adults. Reasonable aphid control in greenhouses can be achieved by a spray formulation containing the 1% oil as potential contact-action fumigant.

Due to its rapid development of resistance to nearly all arrays of acaricide, Tetranychus urticae is extremely hard to control using conventional acaricides. As an alternative control measure of acaricide-resistant mites, RNA interference (RNAi)-based methods have recently been suggested. A double-stranded RNA (dsRNA) delivery method using multi-unit chambers was established and employed to screen the RNAi toxicity of 42 T. urticae genes. Among them, the dsRNA treatment of coatomer I (COPI) genes, such as coatomer subunit epsilon (COPE) and beta 2 (COPB2), resulted in high mortality [median lethal time (LT50) = 89.7 and 120.3h, respectively]. The transcript level of the COPE gene was significantly (F3,9 = 16.2, P =0.001) reduced by up to 24% following dsRNA treatment, suggesting that the toxicity was likely mediated by the RNAi of the target gene. As a toxicity enhancement strategy, the recombinant dsRNA was generated by reciprocally recombining half-divided fragments of COPE and COPB2. The two recombinant dsRNAs exhibited higher toxicity than the respective single dsRNA treatments as determined using LT50 values (79.2 and 81.5h, respectively). This finding indicates that the recombination of different genes can enhance RNAi toxicity and be utilized to generate synthetic dsRNA with improved RNAi efficacy.

Toxicity test of contaminate soil is very complex because of differential bioavailability in the soil. Therefore, bioavailability of metals in soil is a major factor influencing estimates of toxicity. In this study, the two major test was conducted. First, the toxicity of arsenic for the Collembola, Paronychiurus kimi, was assessed by determining the effects of increasing arsenic concentration on survival, reproduction and body concentration of As in five forested soils with different available phosphate and oxide-metal concentration. Second, the sequential extraction procedure (SEP) for arsenic by choosing extraction reagents commonly used for sequential extraction of metals was tested. The EC50 based on total As concentration in soil was estimated respectively. The available phosphate and oxide-metal concentration in soil influenced on As fraction in soil. Especially, As in soil which is non specifically and specifically sorbed (fraction 1, 2) has strong correlation with available phosphate and oxide-metal concentration (p<0.05). The toxicity is more higher in the soil with high available phosphate and low oxide-metal concentration. In addition, the high arsenic concentration in fraction which is amorphous and poor-crystalline hydrous oxide of Fe and Al (fraction 3) had effect to the toxicity. As a result, the toxicity of As is related with As concentration in fraction 1, 2 and 3 and the soil properties and the arsenic fractionation in soil have a influence on the bioavailability and toxicity.