• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.47-54
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• 1996

To search herbicidal compounds in Pulsatilla koreana Nakai, methanol extract of P. koreana roots was purified by sequences of XAD-7 column chromatography, silica gel adsorption column chromatography, silica gel flash column chromatography, preparative layer chromatography and preparative high performance liquid chromatography(Prep, HPLC).The final Prep. HPLC gave two herbicidally-active fractions. These fractions treatment at 100ppm inhibited the root length of Echinochloa crus-galli seedlings by 48% and 60% as compared with the control, respectively. Components in the two active fractions were analyzed by GC-MS Spectrometry. These compounds, which were isolated from P. koreana roots, were identified as several fatty esters, hydrocarbons, squalene, evidonol, and a diazepin analogue.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.90-94
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• 1995

Post emergence herbicidal activities$(pI_{50})$ of X-substituted phenylvinylsulfone derivatives(S) in-vivo against rice(Oryza sativa L.), Barnyard grass(Echinochloa crus-galli) and Pickerelweed(Monochoria vaginalis Presl) were measured by the pot test under paddy conditions. The (S) showed herbicidal symptom rapidly with lower activity(average $pI_{50}=2.0$) as proherbicide, which was excellent tolerance to rice. The structure activity relationships(SAR) were analyzed using such a physicochemical parameters as hydrophobic$({\pi})$ and molecular orbital(MO) quantity by the multiple regression technique, and discussed with quantum pharmacology. The herbicidal activities were related to the hydrophobic$({\pi})$ effect of X-substituent and orbital(HOMO & LUMO) energy. In case of Pickerelweed, the effect was rationalized by parabolic function of ${\pi}$ constant, where the optimal value of ${\pi}$ was 1.10. An increase in hydrophobicity and negative orbital energy by the electron attracting X-substituent may contribute to the herbicidal activity. Based on results proposed from SAR analysis, the mode of herbicidal action could be assumed.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.69-71
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• 2000

The herbicidal activities ($pI_{50}$) with alkoxy (RO-) groups on the azomethine nitrogen atom in 5-(2,3-dihydro-2,2-dimethylbenzothiophene-7-yl)-2-(1-(alkoxyimino)butyl)-3-hydroxy-2-cyclohexene-1-one derivatives against various weeds were measured in the flooded and in the paddy conditions. Particularly, i-propoxy subsutuent, 5 of them showed excellent herbicidal activity at a rate of 4kg/ha with pre-emergence against barnyard grass (Echinochloa crus-galli) with good selectivity on rice plant (Oryza sativa). The results of the structure-activity relationships (SAR) analyses are shown that the alkyl subsituents with higher hydrophobicity (logp>0) and electron donating (${\sigma}^*<0$) group as a new substrate rather than alkoxy substituents seems to be contribute to the herbicidal activity with pre-emergence.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.9-17
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• 2008

QSARs (Quantitative structure-activity relationships) between a series of new cyclohexanedione derivatives (5-benzofuryl-2-[1-(alkoxyimino)-alkyl]-3-hydroxycyclohex-2-en-1-ones) and their herbicidal activity against Rice plant (Oryza sativa L.) and Barnyard grass (Echinochloa crus-galli.) were discussed quantitatively using 2D-QSAR and holographic (H) QSAR methods. Generally, the HQSAR models have better predictability and fitness than the 2D-QSAR models. The herbicidal activities against Barnyard grass with 2D-QSAR II model were dependent upon Balaban indice (BI) of molecule and hydrophobicity of $R_1$ and $R_3$ group. And also, the $R_3=ethyl$ group, according to the information of the optimized HQSAR IV model, was more contribute to the herbicidal activities against Rice plant, while the 5-(cyclohex-3-enyl)-2,3-dihydrobenzofuran ring part was not contribute to the herbicidal activities against two plants.

• Applied Chemistry for Engineering
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• v.19 no.2
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• pp.151-156
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• 2008

The annals of Joseon Dynasty is the most valuable resource containing the record of Korean history and has been known as one of the UNESCO's Memory of the World Register. There was a period that the annals of Joseon Dynasty was used with beeswax to control pests. It is considered as the prior reason of damage on the annals of Joseon Dynasty. Therefore, in this study we analysed the spectrum of traditional paper inside and outside of Korea, beeswax and accelerated artificial aging paper to restore the waxed volume in the annals of Joseon Dynasty by using FT-IR. As a result of FT-IR analysis, spectrum did not showed its big difference in all paper used in this study. However, there was a different spectrum in paper which was made with not Broussonetia kazinoki, but Echinochloa crus-galli var. frumentacea and Dioscorea batatas. Among traditional papers in various countries, spectrum of Korean paper showed the most similarity from the annals of Joseon Dynasty. In comparison between accelerated artificial aging paper and waxed volume, we could identify the change of spectrum affected by the damage.

• Journal of Life Science
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• v.24 no.11
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• pp.1157-1167
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• 2014

In order to compare the anti-inflammatory effects of five selected cereal grains-proso millet, hwanggeumchal sorghum, foxtail millet, barnyard millet, and adlay-the inhibitory activities of 80% ethanol (EtOH) extracts obtained from the individual grains on lipopolysaccharide (LPS)-induced nitric oxide (NO) generation were investigated in RAW264.7 cells. The EtOH extract of barnyard millet (Echinochloa crus-galli var. frumentacea) grains exhibited more potent anti-inflammatory activity than that of the other grains. When the EtOH extract of barnyard millet grains was sequentially fractionated with n-hexane, methylene chloride (MC), ethyl acetate (EtOAc), and n-butanol, the majority of the anti-inflammatory activity was detected in the MC fraction, followed by the EtOAc fraction. Pretreatment with the MC fraction caused downregulation of the expression levels of iNOS- and COX-2-specific transcripts and proteins, as well as proinflammatory cytokine gene transcripts (IL-$1{\beta}$, IL-6, and TNF-${\alpha}$) in LPS-stimulated RAW264.7 cells. Additionally, the MC fraction could suppress not only the LPS-induced nuclear translocation of cytosolic NF-kB, but also the LPS-induced activation of MAPKs, such as ERK, JNK, and p38MAPK. Further analysis of the MC fraction by HPLC identified kaempferol, biochanin A, and formononetin as the major phenolic components. Both kaempferol and biochanin A, but not formononetin, could exert anti-inflammatory effect at the same concentrations as those of the MC fraction. Consequently, these results indicate that kaempferol and biochanin A are among the most effective anti-inflammatory phenolic components in barnyard millet grains. This finding suggests that barnyard millet grains and the MC extract enriched in kaempferol and biochanin A could be beneficial functional food sources that have an anti-inflammatory effect.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.282-291
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• 1996

This experiment was conducted to investigate the phytotoxicity of several herbicides for rice and weed control with herbicides application times and seeding times in flooded direct-seeded rice field. The phytotoxicity of herbieides(bensulfuron methyl+dimepiperate, bensulfuron methyl+mefenacet+dymron, bensulfuron methyl+quinclorac, pyrazosulfuron-ethyl+molinate, pyrazosulfuron-ethyl+thiobencarb, pyrazosulfuron-ethyl+cyhalofop, imazosulfuron+molinate, imazosul-furon+cyhalofop) for rice in different seeding dates was the most high at 7 days after seeding(DAS) Followed by 12 and 17 DAS. In particular, the bensulfuron methyl+mefenacet+dymron showed very high phytotoxicity to rice plants. Weed species occurred in direct-seeding field seeded on May 1 were 10 species (grasses ; 1, broad-leaves ; 6, sedges ; 3) and Echinochloa crus-galli was the most dominant weed among them. Whereas weed species occurred rice field seeded on May 22 were 7 species(grasses ; 1, broad-leaves : 3, ridges ; 3) and Echirochloa crus-galli was the most dominant weed among them. The weed control for annual weeds(Echinochloa crus-galli, Aneilema keisak, and so on) and perennial weeds(Cyperus serotinus, Scipurus juncoides) was remarkably effective at the application of 7 and 12 DAS, but it of Eleocharis kuroguwai was effective at the application of 17 DAS on two seeding times. The yields were decreased significantly at the plot affected severely by herbicides applied at 7 DAS and the plots showed low efficacy at herbicides application of 17 DAS.

• Korean Journal of Weed Science
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• v.15 no.3
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• pp.183-187
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• 1995

The germination characteristics of Diplachne fusca (L.) P. Beauv. seeds were investigated under different seed storage conditions to find out reliable system for maintaining the seeds with high and uniform germination rate and thus for possible use of the seeds in herbicide screening with a continuous seed supply. When the seeds were stored under wet-low temperature($4^{\circ}C$) condition, the germination rate was 88% after 4-week-storage. The germination rate slightly declined after the storage for longer than 3 months. Dry seeds stored at room temperature exhibited very low germination rate. The wet-low temperature treatment was effective for inducing the germination of the seeds which had been stored under dry-room temperature condition for 4 months. The germination rate was 70% after 2-week- storage under the wet-low temperature condition. The germination rate was much higher under an alternate temperature condition than under a continuous temperature condition. The optimum temperature was 35/$25^{\circ}C$(14/10hrs). The seeds had a capability to germinate under NaCl-treated condition even at a concentration of 1.0%, whereas the germination of Echinochloa crus-galli seeds was completely inhibited by 0.5% NaCl. This result indicates that D. fusca has an advantage over E. crus-galli to survive in reclaimed 1and from the sea.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.287-294
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• 1991

The relationships between the quantitative structure of benzotriazoles and their post-emergence growth inhibiting activity$(pI_{50})$ against Oryzae sativa L. and Echinochloa crus-galli were investigated using a generalized quantitative structure activity relationships (QSAR). According to the QSAR analysis, the free radical parameter $(E_R)$ is a very important factor and the growth inhibiting activity values showed parabolic relation to $E_R$ parameter of para-substituents(X). The activity of (3) was superior to those of (4) and (3b) is selected as the most highly effective compound. The optimal values of $E_R$ parameter of the growth inhibiting activity aganist E.crus-galli are $E_R(3)=0.52\;and\;E_R(4)=0.15$, respectively. From the result of molecular design, the substituents(X) of electron withdrawing properties and $E_R$ parameter of optimal value(0.52) were most desirable for high activity of the benzotriazoles. And in view of this, benzotriazoles may also be effective in blocking the photosynthetic electron transfer.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.238-242
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• 2006

The herbicidal activities against the pre-emergence of rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-gall) with changing substituents $(R_1-R_4)$ of new 5-benzofuryl-2-[1-(alkoxyimino) alkyl]-3-hydroxycyclohex-2-en-1-one derivatives as substrate molecules were studied quantitatively using comparative molecular field analyses (CoMFA). The optimized CoMFA models (rice plant: A5 & barnyard grass: B3) were derived from atom based fit alignment and a combination of CoMFA fields. The two models for herbicidal activity against two plants showed the best predictability and fitness ($q^2$>0.6 & ${r^2}_{ncv.}$>0.94) for the herbicidal activities. Also, CoMFA-HINT contour maps showed that the selective herbicidal activity between rice plant and barnyard grass depends on the hydrophobicity of $R_2\;and\;R_3$ groups in molecule. Therefore, it is expected that the herbicidal activity against barnyard grass will be improved by the introduction of the steric bulk small and hydrophobic group.