• Journal of Applied Biological Chemistry
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• v.42 no.2
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• pp.57-61
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• 1999

Seven numerically dominant 2-methyl-4-chlorophenoxyacetic acid (MCPA)-degrading bacteria were isolated from agricultural soils. The isolates utilized the herbicide MCPA as a sole carbon source, producing significant biomass in MCPA mineral medium. They exhibited diverse herbicide degradation capabilities, but most of them grew very slowly in mineral medium containing herbicide. The chromosomal DNA patterns of the isolates obtained by polymerase chain reaction amplification of repetitive extragenic palindromic sequences were distinct from each other. One isolate, SH3, which was identified as Sphingomonas species by fatty acid methyl ester analysis, was able to degrade 5 different phenoxyacetic acid herbicides within 4 days. This strain contains two plasmids, and the smaller one has a crucial role in herbicide degradation. MCPA treated into agricultural soils without indigenous MCPA-degraders persisted for a long time, but the application of the isolate SH3 resulted in rapid decline of MCPA concentration in the soil.

• Applied Biological Chemistry
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• v.44 no.3
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• pp.162-166
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• 2001

Effects of light, methyl jasmonate(MJ), 6-benzylaminopurine(BA), thidiazouron(TDZ), and 2,4-dichlorophenoxyacetic acid(2,4-D) on the contents of ecdysteroids (${\beta}$-ecdysone+polypodine B) in Polypodium vulgare L. and Achyranthes japonica Nakai were studied. When the plants of P. vulgare were cultured under light control, the ecdysteroids contents in both leaves and rhizomes decreased with increasing light intensity. The ecdysteroids contents in A. japonica were also lower when cultured under light than under dark. Among the tested plant growth regulators, MJ, BA, and TDZ increased the ecdysteroids contents in both P. vulgare and A. japonica.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.53-53
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• 2023

Abeliophyllum distichum, one of the Korean endemic plant, is a significant pharmaceutical plant resource. A. distichum with phenylethanoid glycoside can use to regulate the development of cancer, DNA damage with radicals, and the generation of inflammatory mediators. In this study, we investigated whether the biomass, content of phenylethanoid glycoside, and growth rate of callus derived from A. distichum (cultivar Okhwang1, CAD) change in the absence or presence of plant hormones (2,4-Dichlorophenoxyacetic acid; 2, 4-D and 1-Naphthaleneacetic acid; NAA). The results showed that the best biomass, the growth rate of callus, and the contents of phenylethanoid glycoside were cultivated on Murashige and Skoog (MS) growth medium fortified with 1 ppm 2,4-D + 2 ppm NAA after 4 weeks. In a further study, CAD was cultivated on MS growth medium fortified with an elicitor (Methyl Jasmonate, MeJA). The results showed that CAD turned to brown color and fragile form with the elicitor. HPLC-PDA analysis revealed that the contents of phenylethanoid glycoside in the elicitor-treated group were higher than in the elicitor-non-treated group. These results are consistent with the findings of Arano-Varela H et al.,'s study which is that acteoside production can increase after the treatment of MeJA. Therefore, this study can be used to develop an effective and sustainable production of useful substances as an alternative to plant cultivation.

• Journal of Microbiology
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• v.41 no.1
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• pp.7-15
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• 2003

Nine dichlorprop-degrading bacteria and three pairs of bacteria showing syntrophic metabolism of the herbicide were isolated from soils, and their genetic and phenotypic characteristics were investigated. Analysis of 16S rDNA sequences indicated that the isolates were related to members of the genera, Sphingomonas, Herbaspirillum, and Bradyrhizobium. Twelve different chromosomal DNA patterns were obtained by polymerase-chain-reaction (PCR) amplification of repetitive extragenic palindromic (REP) sequences from the 15 isolates. The isolates were able to utilize the herbicide dichlorprop as a sole source of carbon and energy and their dichlorprop derogative pathways were induced by the presence of dichlorprop. Most of the isolates and syntrophic pairs were able to degrade both (R)- and (S)-dichlorprop, but strain DP522 exhibited enantioselective degradation of (S)-dichlorprop. The isolates degraded 2,4-dichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid , and mecoprop, in addition to dichlorprop. Oxygen uptake experiments indicated that most of the isolates degraded dichlorprop through 2,4-dichlorophenol.

• BMB Reports
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• v.32 no.1
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• pp.51-59
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• 1999

The Korean radish cationic peroxidase (KRCP) promoter, comprising nucleotides -471 to +704 relative to the transcriptional initiation site, was fused to the GUS gene and transformed to tobacco BY-2 cells. We examined how auxin (2,4-dichlorophenoxyacetic acid, 2,4-D), cytokinin (6-benzylaminopurine, BAP), gibberellic acid ($GA_3$), abscisic acid (ABA), methyl jasmonate (MeJA), and phosphatidic acid (PA) affect the GUS expression in the presence or absence of 2,4-D in a modified LS medium. Exogenous 2,4-D or BAP greatly decreased the GUS expression regulated by the KRCP promoter in a modified LS medium containing 0.2 mg/l 2,4-D. $GA_3$ increased the GUS expression and ABA completely reduced the inductive effect of $GA_3$. The GUS expression was also increased dose-dependently by plant defense regulators, MeJA and PA. In contrast to the above results, auxin deprivation from the modified LS medium increased the GUS expression after treatment with exogenous 2,4-D whereas BAP still greatly decreased the GUS expression dose-dependently. $GA_3$ or MeJA slightly decreased the GUS expression. The data suggest that auxin deprivation changes the sensitivity of the suspension cells to exogenous chemicals and that the regulation of the KRCP promoter by 2,4-D, $GA_3$, and MeJA is dependent on auxin, whereas the regulation by BAP is not. This study will be valuable for understanding the function and expression mode of the Korean radish cationic peroxidase in Korean radish.

• Journal of the Korean Chemical Society
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• v.59 no.3
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• pp.225-232
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• 2015

A liquid chromatography-electrospray ionization-tandem mass spectrometry method (LC-ESI-MS/MS) was used for determining seven pesticides (2,4-dichlorophenoxyacetic acid, methomyl, aldicarb, 2-methyl- 4-chlorophenoxy- acetic acid, molinate, carbaryl and carbofuran) and two synthetic materials (quinoline and bisphenol-A) in surface water. The analytes were extracted using solid-phase extraction (SPE). The eluate was concentrated by nitrogen gas. 100 microliters of 30% (v/v) methanol aqueous solution were used to dissolve the residue and an aliquot of the reconstituted solution was directly injected into LC-ESI-MS/MS after the filtration using 0.2 μm polytetrafluoroethylene (PTFE) syringe filter. Under the established condition, the calibration curves of the analytes were linear with correlation coefficients of above 0.997. The quantification limit was 0.002~0.011 μg/L and the relative standard deviations were less than 16.4%. In addition, accuracy was in the range of 84~107% and the recoveries were values between 56.2 and 98.6%. In this study, the developed method was applied to the analysis of real surface water samples.

• Korean Journal of Weed Science
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• v.10 no.4
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• pp.277-284
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• 1990

The response of rice (Oryza sativa L.) cultivars to mixtures of 2, 4-D(2, 4-dichlorophenoxyacetic acid) and other herbicides was investigated to determine if there was an interaction between them. When 2, 4-D was applied, shoot growth of Taipei 309 was more affected than that of IR28 at all concentrations used. In contrast, when thiobencarb (S-[(4-chlorophenyl)methyl]diethylcarbamothioate), butachlor [N-(buthoxymethyl) -2-chloro-N-(2, 6-diethylphenyl) acetamide], and glyphosate [N-(phosphonomethyl)glycine] were applied, the shoot growth of Taipei 309 was less affected than that of IR28 at all herbicide concentrations. Combination of 2, 4-D and the lowest thiobencarb concentration was antagonistic for shoot length for both cultivars, but at higher concentrations, it was synergistic. Synergism for shoot fresh weight between 2, 4-D and thiobencarb was observed with IR28 at all concentrations but, for Taipei 309, synergism was observed only at lower 2, 4-D concentrations. Mixing 2. 4-D with butachlor resulted in greater inhibition in shoot length and fresh weight of IR28 than Taipei 309 at all concentrations indicating a synergistic interaction. With combinations of 2, 4-D and glyphosate, an antagonistic interaction for shoot length was observed for both cultivars. A synergistic interaction for shoot fresh weight was observed with IR28 when combinations of the highest concentration of glyphosate and 2, 4-D were applied but there was an antagonistic interaction with Taipei 309.