• 한국어병학회지
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• 제13권1호
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• pp.1-6
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• 2000

항균성세균을 이용하여 어류질병을 control 하기 위한 기초 연구로서 Vivrio anguillarum에 대하여 항균력을 갖는 세균(Probiotic strain=Probiont)을 분리하여 in vitro상에서 항균력을 조사하였다. 분리된 항균성 균주는 Pseudomonas aeruginosa JYMB1-3로 명명되었으며, 본 균주는 Edwardsiella tarda와 Streptococcus sp.에 대하여 동시에 항균력을 나타내었으나 Vibrio종에 대하여 특이적으로 높은 항균력을 갖고 있었다. 한편 항비브리오성 물질은 세균내에서 생산되어 균체외로 분비되는 것으로 보이며 약 $10^7$ cells의 P. aeruginosa JYMB1-3가 24시간 동안 증식하면서 생산한 항균성 물질은 Chloramphenicol $2.5{\mu}g$정도에 해당하는 vibriostatic activity를 보였다.

• 한국응용곤충학회지
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• 제31권4호
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• pp.475-479
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• 1992

곤충탈피호르몬의 비스테로이드계 길항제인 RH 5849는 엽침적법으로 처리했을 때 담배거세미나방(Spodoptera litura)의 전 유충 발육단계에 걸쳐서 거의 비슷한 $LC_{50}$ 값을 보여주었다(18.1~26.5 ppm). 4령 유충에서 섭식저해율은 처리농도에 따라 비례하였고, 4.2ppm 으로 엽침적처리된 양배추 엽편을 먹은 3령 유충의 체중증가는 처리 후 48시간 이후부터 정체되었다. 양배추와 담배의 전 식물체에 대한 RH 5849의 침투성 약효발현이 관찰되었는데, 약 20ppm(mg/kg soil)이하의 $LC_{50}$ 값이 양배추에서는 15일, 담배에서는 30일 가량 지속되었다.

• 한국식품과학회지
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• 제44권5호
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• pp.634-637
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• 2012

딸기병해는 생육기 동안 과실의 생산량감소 및 품질저하를 가져오고 있으며, 약제방제의 어려움 등으로 인해 친환경적인 병해 방제법의 개발이 요구된다. 실내에서 자외선(UV-C, 264 nm)조사에 의한 딸기병원균의 균사생장 억제효과를 구명하기 위하여 5종의 딸기병원균을 자외선을 조사하면서 $25^{\circ}C$ 항온실에서 배양한 후 균총의 직경을 측정하였다. 5종의 딸기병원균을 PDA 상에서 배양하면서 자외선을 조사하면, 하루 1시간 조사에 의해서도 생장이 억제되었고 9-12시간을 조사한 균의 생육은 현저하게 억제되었으며 역병균은 생육이 완전하게 억제되었다. 자외선광원과 병원균의 거리에서는 40-50 cm의 거리에서 자외선을 조사한 배양기에서 병원균생장의 억제효과가 크게 나타났다. 배지에 접종한 후 바로 자외선을 처리한 병원균은 모두 2일간 배양한 후 자외선을 접종한 배양기에서보다 생육이 억제되었다. 딸기 탄저병균(C. gloeosprioides)과 시들음병균(F. oxysporum)은 V8A에서 자외선에 의한 균의 생장억제효과가 큰 것으로 나타났다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.401-411
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• 2006

The cationic chitosan is prepared in this paper. This kind of cationic chitosan is a good retention aid for bleached hardwood pulp, the filler retention increased by 33.0% when the cationic chitosan (DS=1.27) dosage was 0.05%. Because many of the materials used in papermaking process are excellent microbiological nutrients, these nutrients will result in the growth of bacteria; uncontrolled growth of bacteria and fungi in the papermaking process adversely affects machine runnability. According to the standard methods of microbe growth inhibition test, cell counting was conducted after proper cultivated time. This paper explored the factors that affecting the cationic chitosan's antibacterial effect.

• Journal of Plant Biology
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• 제32권1호
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• pp.41-49
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• 1989

Phenolic compounds such as gallic acid, ferulic acid, p-hydroxybenzoic acid, vanillic acid, salicylic acid, tannic acid, and hydroquinone were identified from the aqueous extracts and volatile substances of tomato plant by paper chromatography, high performance liquid chromatography and gas chromatography. The seed germination and seedling growth of the experimental species, lettuce and egg plant, were severely inhibited in 5$\times$10-3M of phenolic reagents identical to those identified from tomato plant. Germination and growth rate of test species in 5$\times$10-4M and 5$\times$10-5M were higher than that of 5$\times$10-3M. Therefore, 5$\times$10-3M of phenolic compounds would be assumed to be threshold concentration for allelopathic effects.

• 한방재활의학과학회지
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• 제30권1호
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• pp.31-45
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• 2020

Objectives In this study, we investigated the antimicrobial activity of a 70% ethanol extract of Maneung-hwan (MEH), which is prescribed by practitioners of oriental medicine for use against methicillin-resistant Staphylococcus aureus (MRSA). Methods The antibacterial activity of MEH against MRSA strains was evaluated using the disc diffusion method, broth microdilution method (minimal inhibitory concentration, MIC), checkerboard dilution test, and time-kill test. The mechanism of action of MEH was investigated by bacteriolysis using detergents or ATPase inhibitors Additionally, mRNA and protein expression were investigated by quantitative reverse transcription-polymerase chain reaction and western blot assay, respectively. Results The MIC of MEH was 25~1,600 ㎍/mL against all the tested bacterial strains. We showed that MEH extract exerts strong antibacterial activity. In the checkerboard dilution test, the fractional inhibitory concentration index of MEH in combination with antibiotics indicated synergism or partial synergism against S. aureus. The time-kill study indicated that the growth of the tested bacteria was considerably inhibited after a 24-h treatment with MEH and selected antibiotics. To measure the cell membrane permeability, MEH (3.9 ㎍/mL) was combined with Triton X-100 (TX) at various concentrations N,N-dicyclohexylcarbodimide (DCCD) was also tested as an ATPase inhibitor. TX and DCCD cooperation against S. aureus exhibited synergistic action. Accordingly, the antimicrobial activity of MEH in the context of cell membrane rupture and ATPase inhibition was assessed. Additionally, the expression of genes and proteins associated with resistance was reduced after exposing MRSA to MEH. Conclusions These results suggest that MEH possesses antibacterial activity and acts as a potential natural antibiotic against MRSA.

• 생약학회지
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• 제21권2호
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• pp.142-147
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• 1990

Yew cortex, twigs and leaves(Florida yew, Taxus floridana Nutt et Champ; Pacific, yew Taxus brevifolia Nutt(Taxaceae)) were extracted with MeOH and $CHCI_3$, respectively, and then the chloroform extract was fractionated by silica column chromatography. As biologically active substances, taxol derivatives were identified and several biological activity tests were followed. The results showed that it bad no antimosquito activity and inhibited the growth of root meristem of cress seeds. The chloroform ext. of Florida yew showed 91%, inhibition rate at 400 ppm and the taxol fractions of Pacific yew did 91% at 200 ppm, 94% at 100 ppm. In the antitumor activity tests in vitro against a cultured cell line of L1210 mouse leukemia, Pacific yew showed 99% inhibition rate at 1.0 ppm and Florida yew did 97% at 10 ppm.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.423-430
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• 2002

The effects of UV-B and commercial grade pesticides (butachlor and carbofuran), individually and in combination, were studied on a variety of physiological processes of rice field cyanobacterium Anabaena doliolum. Butachlor was found to be $2-12\%$ more toxic than carbofuran and $4-24\%$ than UV-B on the growth, photosynthesis, lipid peroxidation, membrane permeability, and nitrogenase activity of the test cyanobacterium. Of the three photosynthesis inhibitors, the butachlor-induced inhibition of whole chain was approximately 3 and $21\%$ higher than carbofuran and UV-B, respectively. Although the interaction of the stress factors caused a significant inhibition (P<0.01), it was still less than the additive effect on the parameters investigated, except for PSI.

• Archives of Pharmacal Research
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• 제27권9호
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• pp.915-918
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• 2004

By bioassay-guided separation, an already known saponin, Pulsatilla saponin D was isolated from the root of Pulsatilla koreana Nakai as a antitumor component when evaluated by in vivo antitumor activity as well as in vitro cytotoxic activity test. It showed potent inhibition rate of tumor growth (IR, 82％) at the dose of 6.4 mg/kg on the BDF1 mice bearing LLC cells.

• 약학회지
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• 제28권2호
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• pp.89-95
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• 1984

Microorganisms having beta-latamase inhibitory activity were selected from soil samples collected from 63 spots throughout the country. Screening procedures consist of two steps. Those are growth inhibition test of penicillinase-producing Staphylococcus aureus by double-layered agar plate containing penicillin G as a substrate, and that of penicillin sensitive Staphylococcus aureus ATCC 6538 in the similiar condition including penicillinase. Finally, a strain was selected from a soil sample of Pa-ju, Kyeong-gi Do. This strain was classified as a Streptomyces sp. by ISP(International Streptomycete Project) and Bergey's manual.