• Journal of Plant Biology
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• 제30권1호
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• pp.11-20
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• 1987

Phenolic compounds, p-coumaric and p-hydroxybenzoic acids, known as inhibitors for development and growth of many pioneer species on early stage of succession were used for the test fo susceptibility in various herbs collected from abandoned agricultural fields in the vicinity of Amherst(U. S. A.). The percent inhibition was generally greater for p-coumaric acid than for p-hydroxybenzoic acid. Concentrations of 5$\times$10-5 and 5$\times$10-4M generally had no significant effects, but at 5$\times$10-3M was inhibitory to germination and growth of tested species. And the percent inhibition caused by the two phenolics was correlated (r=.843, p<.01). Also the indices of resistance for germination and elongation were significant (r=.695, p<.01) in this study. While Cirsium and Lepidium invading species of early stage of succession were sharply susceptible for toxic activity by phenolic acids.

• Applied Biological Chemistry
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• 제38권4호
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• pp.283-288
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• 1995

시판 농약류의 미생물에 대한 독성을 검정한 결과 제초제인 paraquat(1,1'-dimethyl-4,4'-bipyridylium dichloride)가 편성혐기성 세균을 제외한 세균류와 효모 및 곰팡이에 걸치는 광범위한 미생물의 증식을 저해하였다. Paraquat는 $1.0\;{\mu}M$(0.186ppm)의 농도에서도 공시균(Escherichia coli KCTC 1039)의 turbidometric growth를 지연시켰으나, 생균수 변화 및 well test 등의 결과로부터 공시균에 대한 paraquat의 생육저지 최소 농도는 1.0mM(186ppm)로 평가되었다. Paraquat 처리시 공시균의 생균수는 처리직후에 대조구의 약 50%로 급격히 감소되었으나, 이후 4시간 동안 1.0mM의 paraquat 존재하에서도 유의적으로 증가되었다. 그러나 처리 4시간 이후로는 생균수가 서서히 감소되었으며 계속된 배양에도 불구하고 재증식은 관찰되지 아니하였다.

• 생명과학회지
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• 제18권6호
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• pp.789-795
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• 2008

어류 질병 치료를 위한 probiont의 개발에 목적을 두고 어병균 Vibrio anguillarum NCMB1의 생육에 저해물질을 생산하는 Bacillus amyloliquefaciens H41균주를 분리하고 이 물질의 특성을 규명하기 위하여 정제를 시행하였다. 분리 균을 배양한 배양 상등액을 70% 염석, 투석하여 조 효소액으로 제작하고 조 효소액을 DEAE-sephadex, A-50 ion exchange chromatography, sephadex G-200 gel filtration column chromatography을 통하여 정제하고 SDS-PAGE 를 통하여 단일밴드를 확인하고 최종 회수율 2.9%을 얻을 수 있었으며 40.8배의 정제된 V. anguillarum NCMB1 생육저해물질을 얻을 수 있었다. 정제된 저해물질은 저해정도에 따라 단위를 설정하여 활성을 측정하였으며, 분자량은 48 kDa 로 확인되었으며 정제물질의 활성을 위한 최적 반응 pH와 온도는 pH 7.5와 $30^{\circ}C$로 확인되었다. 금속이온의 효과에 있어서는 $CoCl_2$, $HgCl_2$, $ZnSO_4$, $AgNo_3$에서는 완전히 저해되는 양상을 나타내었고 $MgSO_4$, $MnSO_4$에서 미미한 효소활성의 증가를 나타내었다. 그리고 염에 관한 안정성은 일반 해수의 농도인 3%의 농도에서도 활성을 나타내는 것으로 확인되었다. 정제된 저해물질을 현재 상업적으로 사용하고 있는 화학처리제나 항생제와 함께 효율성을 비교 해 보았을 때 저해물질은 약 78%의 저해 활성을 나타내는 것을 알 수 있었고 항생제보다는 효율성이 낮았으나 독성검사를 위해 정제물질을 살아있는 어류에 투여하였으나 어떤 해수어도 폐사하지 않는 것으로 보아 어류 자체엔 독성을 나타내지 않는 물질로 나타났다. 따라서 B. amyloliquefaciens H41 균주가 생산하는 정제 물질이 V. anguillarum 생육에 저해물질로 작용하는 것으로 밝혀졌으며 친환경적인 특성을 가진 물질로 밝혀졌다.

• 한국식품조리과학회지
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• 제25권3호
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• pp.379-386
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• 2009

The antimutagenic and cytotoxic activities of ethanol and water extracts from Rubus coreanum were investigated in this study. Their antimutagenic activities were measured by the Ames test and their cytotoxic activities were evaluated by the growth inhibition of cancer cells via the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay and the sulforhodamine B (SRB) assay. In the results, the inhibition rates of the ethanol and water extracts toward mutagenicity induced by 4-NQO were 95.0% and 93.6% at 5 mg/plate, respectively, while their inhibition rates against mutagenicity induced by sodium azide were 27.2% and 40.8%, respectively. According to MTT assay, the cytotoxicity values of the ethanol extract against Hep3B and HeLa cells were 67.2% and 68.5%, respectively, and the values for the water extract were 65.8% and 66.4%, respectively. In the SRB assay, the ethanol and water extracts inhibited over 60% of cancer cell growth. In conclusion, both the ethanol and water extracts of Rubus coreanum offer potentially good antimutagenic and anticancer effects.

• Archives of Pharmacal Research
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• 제22권2호
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• pp.143-150
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• 1999

melatonin (MLT), N-acetyl-5-methoxytryptamine, is mainly secreted by the pineal gland. The ultraviolet (UV), infrared (IR) and 1H-NMR spectra of irradiated and non-irradiated MLT were measured, and phototoxicity tests of MLT, anthracence (positive control) and sodium lauryl sulfate (SLS, negative control) were performed. The methods employed include both in vitro test such as MTS assay using the human fibroblast cell and yeast growth inhibition assay using Candida albicans and in vivo method using the skin of guinea pig. UV absorption spectra and 1H-NMR spectra of MLT were changed by UVA (365 nm, 15 J/$\textrm{cm}^2$), but IR spectra of MLT were not changed. The fifty percent inhibitory concentration (IC50) ratio (UV-/UV+) of MLT was 10. The inhibition zone of irradiated-paper disks treated with MLT was not observed. According to the results of histophathological examination, no pathologic lesion was observed in the non-irradiated group, but slight degeneration of keratinocytes in the epidermis, homorrhage and vasodilation in dermis were observed in the irradiated group. These results indicated that the molecular structure of MLT is altered by UVA to unidentified photoproducts and a moderate phototoxicity of MLT is predicted.

• 상하수도학회지
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• 제19권5호
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• pp.639-646
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• 2005

In this research, we tried to develop the application method to water management and treatment using toxicity test method. When we measure the toxicity of environmental samples, we have to decide whether we take some countermeasures to reduce the toxicity or not. The first issue is how to set these action levels in each bioassays. A new idea was attempted to authorize indirect approach of each bioassays through the response characteristics against mixture of chemicals in water quality standard. The significant response in the cell-growth-inhibition bioassay was detected for standards-mixture(STDs). For acute toxicity assay, STDs-based implicit correlation between risks to humans and bioassay data showed a rational approach to set action levels in practical management. A simple model was proposed to describe and predict the changes in the total toxicity based on the concentrations of toxic-controlling chemicals during the ozonation of landfill leachates. On the basis of this simple model, toxicity reduction was predicted for pre-aggregation treatment before ozonation and ozone concentration during the ozonation. The method proposed in this study would be useful in optimizing water treatment processes and their running conditions in terms of the toxicity reduction efficacy.

• 펄프종이기술
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• 제40권2호
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• pp.29-36
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• 2008

In order to give pulp surfaces anti-bacterial functionality and photo-catalytic deodorant ability, functional pulps was made using a surface modification method with Ag nano-colloidal solution and $TiO_2$ filler. Hygiene paper was made with the specially modified pulp, and anti-bacterial and deodorant tests were carried out. The Ag nano-colloidal solution was coated on the surface of the pulp using the high pressurized gas phase squirt through the spray nozzle mounted on the hybridization system. The surface modified functional pulp was hybridized with the optimum ratio of $TiO_2$(fine particle) to pulp(core particle) under the condition of $6,000{\sim}10,000$ rpm for $3{\sim}7$ minutes in the system. The anti-bacterial functionality of the hygiene paper was confirmed by the halo test in which the formation of the clear zone around the hygiene paper sample was observed. The inhibition growth test using MIC bioscreen C showed the inhibition growth effect of the bacteria as the reaction time was increased. The photo-catalytic effect measurement of the $TiO_2$ for 4 hours of the reaction showed $50{\sim}60%$ of decomposition rate, reaching over 60% for 5 hours of the reaction.

• 한국잡초학회지
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• 제6권2호
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• pp.168-173
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• 1986

본 연구는 생장억제제(生長抑制製)인 fluazifop-butyl의 제초작용기구(除草作用機構)를 구명하기 위하여 본제초제가 생장의 기본요소인 세포분열(細胞分裂)과 신장(伸長) 그리고 단백질합성(蛋白質合成)에 미치는 영향을 조사하였다. 본제초제를 귀리의 뿌리에 농도별로 처리한 후 0 에서 48 시간까지의 세포분열(細胞分裂)에 미치는 영향을 조사하였다. 또한 세포신장(細布伸長)에 미치는 제초제의 영향은 oat coleoptile straight growth test 방법으로 조사하였다. 단백질함량(蛋白質含量)에 미치는 제초제의 영향은 $^{14}C$-leucine을 뿌리에 흡수 시켜서 합성인제합성유제(合成柳制) 정도를 liquid scintillation counter로 측정했다. 16시간 처리 후 $1{\times}10^{-3}M$과 $1{\times}10^{-4}M$구에서 세포분열을 억제하였다. 18 시간 처리 후 모든 처리구에서 세포분열이 억제되었다. 24 시간 처리 후에는 $1{\times}10^{-3}M$은 100%, $1{\times}10^{-4}M$은 99% $1{\times}10^{-5}M$은 89% 의 세포분열을 억제시켰으나 저농도구인 $1{\times}10^{-6}M$은 같은 처 리 기간동안에 20%의 세포분열만을 억제시켰다. 농도와 처리시간이 증가함에 따라 억제효과(抑制效果)도 증가하였다. 억제효과가 가장 크게 나타난 기간은 처리후 0 에서 18 시간 이내에 나타났다. 본 제초제의 세포신장억제 효과는 $1{\times}10^{-7}M$ 이상의 고농도에서 유의성(有意性)을 나타냈으며 $1{\times}10^{-6}M$ 이상의 고농도에서는 50% 이상의 세포 신장억제를 보여 주었다. 단백질합성에 관한 조사에서는 8 시간 처리후에 60%의 단백질합성이 억제되었다. 이상의 결과를 종합하여 볼 때 fluazifopbutyl의 식물생장(植物生長) 억제기구(抑制機構)는 세포분열과 신장 그리고 단백질합성을 억제함으로써 기인된 것으로 시료된다.

• Journal of Microbiology and Biotechnology
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• 제13권4호
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• pp.544-551
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• 2003

Interactive effects of UV-B and Cd on growth, pigment, photosynthesis, and lipid peroxidation have been studied in Anabaena, Microcystis, and Nostoc; all the tested cyanobacteria showed differential sensitivity to different dosage of UV-B and Cd alone as well as in combination. Phycocyanin was severely affected by UV-B and Cd by all the strains; the degree of pigment bleaching was most pronounced in Anabaena followed by Microcystis and Nostoc. $UV-B_2+Cd_2$ produced nearly 83, 78, and 65% inhibition of phycocyanin in Anabaena, Microcystis, and Nostoc, respectively. The above treatment also significantly decreased the contents of Chl ${\alpha}$ and carotenoid. Presence of capsule in Microcystis protected the phycocyanin bleaching as compared to decapsulated cells. Laboratory-grown Microcystis revealed about 75 and 80% inhibition, following $UV-B_2+Cd_2$ treatment, respectively. in capsulated and decapsulated cells. Damage caused by Cd was more pronounced than UV-B. Inhibition of photosynthesis did occur in all the test strains, being maximum in Anabaena. PS II was the most sensitive component of the electron transport chain, showing 84, 80, and 70% inhibition in Anabaena, Microcystis, and Nostoc, respectively. As compared to control, significant lipid peroxidation (6.5-fold higher) was observed in Anabaena with $UV-B_2+Cd_2$, $^{14}C-uptake$ was more susceptible to Cd and Uv-B than oxygen-evolution. Approximately 84, 80, and 76% inhibition of $^{14}C-uptake$ was observed in Anabaena, Microcystis, and Nostoc, respectively. Similarly, $UV-B_2+Cd_2$ inhibited APT content of Anabaena by 87%. This ,study suggests that inhibition of carbon fixation was due to decreased ATP content of the test cyanobacteria by UV-B+Cd, where Anabaena was the most sensitive and Nostoc the most tolerant.

• 한국물환경학회지
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• 제20권3호
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• pp.197-205
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• 2004

Batch test methods have developed for a long time to measure kinetic and stoichiometric parameters which are required to perform steady state design and mathematical modelling of activated sludge processes. However, at various So/Xo ratios, abnormal behaviors of ordinary heterotrophic organism in batch tests have been reported in many researches. Thus, in this research, abnormal behaviors of heterotrophs in batch tests were investigated at various So/Xo conditions by measuring and interpreting oxygen utilization rate. As So/Xo ratio increased, the calculated values of maximum specific growth rates, ${\mu}_{H,max}$ and $K_{MP,max}$, increased. However, at a certain point of So/Xo (around 10mgCOD/mgMLAVSS), ${\mu}_{H,max}$ and $K_{MP,max}$ values started to decrease. According to this observation, three prominent behaviours of heterotrophs were identified at various So/Xo conditions. (1) At low So/Xo region (below 5 mgCOD/mgMLAVSS), the oxygen utilization rate of heterotrophs in batch tests were almost stable and consequently yielded lower maximum specific growth rate. (2) At high So/Xo region (up to 5~10 mgCOD/mgMLAVSS), oxygen utilization rate incresed sharply with time and indicated more upward curvature than the predicted OUR with conventional activated sludge model, which consists of single hetetrotrophs group. Thus, in this region, competition model of two organisms, fast-grower and slow-grower, seemed to be appropriate. (3) At extremely high So/Xo region (over 10mgCOD/mgMLAVSS), significant oxygen utilization rate was still observed even after depletion of readily biodegradable COD. This might be caused by retarded utilization of intermediates which were generated by self inhibition mechanism in the process of RBCOD uptake.