• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.45-50
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• 2008

Lignans and neolignans are optically active plant secondary metabolites. Research on biosynthesis of lignans has already been advanced especially for the formation of (+) pinoresinol but information on the biosynthesis of 8-O-4'- neolignans is still limited. Moreover, the chemical structure(position of substituents on aromatic rings) and stereochemistry of 8-O-4' neolignans is not clear. Katayama and Kado discovered that incubation of cell-free extracts from E. ulmoides with coniferyl alcohol in the presence of hydrogen peroxide gave (+)-erythro- and (-)-threo- guaiacylglycerol 8-O-4'-(coniferyl alcohol) ether (GGCE)(diastereomeric ratio, 3:2) which is the first report on enzymatic formation of optically active -8-O-4' neolignans from an achiral monolignol. In this aspect, enzymatic formation of guaiacyl 8-O-4' neolignan is noteworthy to clarify its stereochemistry from incubation of coniferyl alcohol with enzyme prepared from Eucommia ulmoides. In this experiment, soluble and insoluble enzymes prepared from E. ulmoides were incubated with 30 mM coniferyl alcohol(CA) for 60 min. The enzyme catalyzed GGCE, dehydrodiconiferyl alcohol(DHCA), and pinoresinol identified by reversed phase HPLC. Consequently, diastereomeric compositions of GGCE were determined as erythro and threo isomer. Enantiomeric composition was determined by the chiral column HPLC. Both enzyme preparations enantioselectively formed (-)-erythro, (+)-erythro and (+)-threo, (-)-threo-GGCEs respectively.

• Journal of the Korean Wood Science and Technology
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• v.12 no.2
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• pp.27-34
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• 1984

In order to investigate the acidic chlorinated compounds in pulp bleaching spent liquor, the lignin model compounds, coniferyl alcohol(mp $74^{\circ}C$), ${\omega}$-(2-methoxyphenoxy)-acetoguaiacone(mp $93^{\circ}C$) and dehydrodiisoeugenol(mp $133^{\circ}C$), were synthesized and chlorinated by chlorine in glacial acetic acid. From the chlorinated products, the following chlorine-containing aromatic compounds were identified by TLC. In coniferyl alcohol the chlorine-substituted compounds at 4-, 5-and 4,5-position of aromatic nucleus were identified and in ${\beta}$-0-4 type the compounds substituted chlorine for alkyl group and/or hydrogen at land 1,4-position of aromatic nucleus expected to be formed by electrophilic displacement from ${\omega}$-(2-methoxyphenoxy)-acetoguaiacone were not identified but the chlorine-substituted compounds at 4-, 5-, 6- and 5,6-position of aromatic nucleus were identified.

• Korean Journal of Pharmacognosy
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• v.35 no.3 s.138
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• pp.259-263
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• 2004

Twelve constituents were isolated from the MeOH extract of the root of Brassica campestris L. ssp rapa. They were identified as linoleic acid methylester (1), palmitic acid (2), ${\beta}-sitosterol$ (3), 1-methoxyindole-3-acetonitrile (4), indole-3-acetonitrile (5), linolenic acid (6), goitrin (7),4-hydroxycinnamyl alcohol (8), coniferyl alcohol (9), p-coumaroylglucose (11) and feruloylglucose (12), on the basis of spectral data respectively.

• Journal of Korea Foresty Energy
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• v.23 no.1
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• pp.45-68
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• 2004

The word of lignin is derived from the Latin word 'ligum' meaning wood. Lignin is complex polymer consisting of coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol unit and has an amorphous, three dimensional network structure which is hard to be hydrolyzed by acid. Lignin is found in the cell wall of plants lignified. The mode of polymerization of these alcohols in the cell wall lead to a heterogeneous branched and cross-linked polymer in which phenyl propane units are linked by carbon-carbon and carbon-oxygen bonds. This polymerization of precursors, p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol to lignin is formed by enzymic dehydrolyzation. The reaction is initiated by an electron transfer which results in the formation of resonance-stabilized phenoxy radical. The combination of these radicals produces a variety of dimers, trimers and oligomers and so on. Lignin research has been divided into basic and practical application field. The basic studies contains biosynthesis, chemical structure, distribution in the cell wall and reactivity by reductants, oxidants and organic solvents. The application research will be approached the reaction of lignin in various pulp making involving pulp bleaching and its effect on pulp qualities. Lignin also will be studied for the production of fine chemicals, polymer products and the conservation into an energy source like petroleum oil because the amount of lignin produced in pulp making process is more than 51,000,000 tons per year in the world. Both basic and application research must lay emphasis on the development for the utilization of lignin and the pulping process. But these researches can not be completed without understanding lignin structure containing functional groups. Therefore, this paper was focused on the review of lignin formulation which has been studied since 1948 in chronological order. This review was based on monomers, dimers, trimers and tetramers of phenyl propane unit structures which were isolated and identified by different methods from various wood.ious wood.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.702-703
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• 2005

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.206-206
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• 2004

• Korean Journal of Pharmacognosy
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• v.38 no.4
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• pp.403-408
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• 2007

xBrassicoraphanus is an intergenic breed crossed between Brassica campetris L. ssp. pekinensis and Raphanus sativus L. that have been daily consumed. xBrassicoraphanus was known to have good tastes and biological activities. Nevertheless, its constituetnts were not elucidated yet. Thus, in the present study, to indirectly evaluate the biological activity of xBrassicoraphanus, 12 compounds were isolated from leaves and roots of xBrassicoraphanus. On the basis of spectroscopic evidences, the structures of these compounds isolated from leaves of xBrassicoraphanus. were identified as ${\beta}-sitosterol$, indole-3-acetonitrile, ferulic acid, methyl ferulate, linolenic acid methyl ester, linolenic acid and coniferyl alcohol, while the chemical structures of compounds isolated from the roots of were xBrassicoraphanus were characterized as ${\beta}-sitosterol$, indole-3-acetonitrile, ferulic acid, methyl ferulate, linolenic acid methyl ester, 1-methoxyindole-3-acetonitrile, goitrin, 4-hydroxycinnamyl alcohol, coniferyl alcohol, palmitic acid and daucosterol. These can be classified as three steroids, two indole cyanides, two cinnamic acid derivatives, one cinnamyl alcohol derivative, three fatty acid derivatives one isothiocyanate. These results suggest that the compounds isolated from xBrassicoraphanus were almost identical with known components of Brassica campetris L. ssp pekinensis or Raphanus sativus L. However, it is necessary to investigate more about the difference of amounts of constituents according to harvest time and variant species amounts.

• Korean Journal of Plant Resources
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• v.11
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• pp.89-109
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• 1998

Screening of new antioxidants form oriental medicines resulted in the isolation of a new antioxidative compound and eight known compounds from the stem bark of Kalopanax pictus. On the basis of various spectrosopic studies, the structure of the new compound was determined to be 4-rhamnose-3,5-dimethoxybenzoic acid methly ester. Other known compounds were identified as ferulic acid, 4,5,6,-trihydroxyflavanone, 2', 4',4' -trihydroxychalcone, caffeic acid, coniferyl alcohol, syringin, 1,3-di-O-caffeoylquinic acid. These compounds showed lipid peroxidation inhibitory acitivity in rat liver microsomes and free radical scavenging acitivity.

• Journal of Life Science
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• v.31 no.10
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• pp.944-953
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• 2021

Lignin is a complex phenylpropanoid polymer abundant in the cell walls of vascular plants. It is mainly presented in conducting and supporting tissues, assisting in water transport and mechanical strength. Lignification is also utilized as a defense mechanism against pathogen infection or wounding to protect plant tissues. The monolignol precursors of lignin are synthesized by cinnamyl alcohol dehydrogenase (CAD). CAD catalyzes cinnamaldehydes to cinnamyl alcohols, such as p-coumaryl, coniferyl, and sinapyl alcohols. CAD exists as a multigenic family in angiosperms, and CAD isoforms with different functions have been identified in different plant species. Multiple isoforms of CAD genes are differentially expressed during development and upon environmental cues. CAD enzymes having different functions have been found so far, showing that one of its isoforms may be involved in developmental lignification, whereas others may affect the composition of defensive lignins and other wall-bound phenolics. Substrate specificity appears differently depending on the CAD isoform, which contributes to revealing the biochemical properties of CAD proteins that regulate lignin synthesis. In this review, details regarding the expression and regulation of the CAD family in lignin biosynthesis are discussed. The isoforms of the CAD multigenic family have complex genetic regulation, and the signaling pathway and stress responses of plant development are closely linked. The synthesis of monolignol by CAD genes is likely to be regulated by development and environmental cues as well.

• Genomics & Informatics
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• v.16 no.4
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• pp.34.1-34.9
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• 2018

Cirsium japonicum belongs to the Asteraceae or Compositae family and is a medicinal plant in Asia that has a variety of effects, including tumour inhibition, improved immunity with flavones, and antidiabetic and hepatoprotective effects. Silymarin is synthesized by 4-coumaroyl-CoA via both the flavonoid and phenylpropanoid pathways to produce the immediate precursors taxifolin and coniferyl alcohol. Then, the oxidative radicalization of taxifolin and coniferyl alcohol produces silymarin. We identified the expression of genes related to the synthesis of silymarin in C. japonicum in three different tissues, namely, flowers, leaves, and roots, through RNA sequencing. We obtained 51,133 unigenes from transcriptome sequencing by de novo assembly using Trinity v2.1.1, TransDecoder v2.0.1, and CD-HIT v4.6 software. The differentially expressed gene analysis revealed that the expression of genes related to the flavonoid pathway was higher in the flowers, whereas the phenylpropanoid pathway was more highly expressed in the roots. In this study, we established a global transcriptome dataset for C. japonicum. The data shall not only be useful to focus more deeply on the genes related to product medicinal metabolite including flavolignan but also to study the functional genomics for genetic engineering of C. japonicum.