• Korean journal of applied entomology
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• v.27 no.3
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• pp.138-143
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• 1988

A key to subfamilies, tribes, and genera of Korean bark and ambrosia beetles including unrecorded genus Scolytogenes is provided with general and antennal pictures for identification.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1090-1099
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• 2015

Among the four different parts of mulberry (Morus alba L.) tree, ethanol extract of Morus root bark showed the highest ${\alpha}$-glucosidase inhibitory activity ($IC_{50}=12.01{\mu}g/mL$). Bioassay-guided fractionation of the ethanolic extract of root bark by Diaion HP-20, silica gel, ODS-A, and Sephadex LH-20 column chromatographies led to the isolation of four compounds, including Compound (Comp.) 1 ($IC_{50}=5.22{\mu}g/mL$), Comp. 2 ($IC_{50}=1.78{\mu}g/mL$), Comp. 3 ($IC_{50}=2.94{\mu}g/mL$), and Comp. 4 ($IC_{50}=1.54{\mu}g/mL$) with strong ${\alpha}$-glucosidase inhibitory activities. Their chemical structures were elucidated as morusin (Comp. 1), kuwanon H (Comp. 2), chalcomoracin A (Comp. 3), and chalcomoracin B (Comp. 4) by UV and NMR spectral analyses. These results suggest that prenylflavonoid and mulberrofuran of Morus root bark may be useful as potential therapeutic agents for diabetes.

• Journal of Forest and Environmental Science
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• v.37 no.1
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• pp.52-61
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• 2021

Decay fungi can decompose plant debris to recycle carbon in the ecosystem. Still, they can also be fungal pathogens, which can damage living trees and/or wood material and cause a large amount of timber loss. We isolated and identified basidiomycetous fungi from the decayed bark of Mongolian oak wrapped with sticky roll traps. The degrading enzyme activities were then tested for all fungal isolates. The decay ability of selected isolates was assessed based on the weight loss of wood discs after inoculating with culture suspension of decay fungi under the different humidity levels. A total of 46 basidiomycetous fungal isolates belonged to 12 species, and 10 genera were obtained from Jong Myo (16 isolates), Chang Kyung palace (7 isolates), Cheong Gye (10 isolates), and Gun Po (13 isolates). Gymnopus luxurians was the most dominant fungus in the present study, and this species distributed in all survey sites with 9 isolates in Jong Myo, followed by 3 isolates in Chang Kyung palace, while Cheong Gye and Gun Po had only 1 isolate each. Among 46 isolates, 44 isolates secreted at least one enzyme, while 25 isolates produced both cellulase and phenol oxidase enzymes, and 2 isolates produced neither. The assessment of decay ability by artificial inoculation indicated that the weight loss of wood discs was significantly influenced by humidity conditions when inoculated with bark decay fungi. The percent weight losses by G. luxurians inoculation in RH of 90-100% and RH of 65-75% were 4.61% and 2.45%, respectively. The weight loss caused by Abortiporus biennis were 6.67% and 0.46% in RH of 90-100% and RH of 45-55%, respectively. The humidity reduction approach should be applied for further studies to control the growth and spread of bark decay fungi on the trunks wrapped with sticky roll traps.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.89-94
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• 1996

Three sesquiterpene ortho-naphthoquinones were isolated from the methanolic extract of root bark of Ulmus davidiana Planch whose stem and root bark have been used as an oriental medicine for the treatment of edema, mastitis, gastric cancer and inflammation. The structures of these compounds were established on the basis of spectral data obtained from UV-vis, IR, HR-EIMS and NMR spectrometry, including the pulse field gradient (PFG)-HMQC and HMBC techniques. Their structures were determined as 2,3-dihydro-3,6,9-trimethylnaphtho(1,8-b,c)pyran-7,8-dione, 3,6,9-trimethylnaphtho(1,8-b,c)pyran-7,8-dione and 2,3-dihydro-4-hedroxy-3,6, 9-trimethylnaphtho(1,8-b,c)pyran-7,8-dione, which were identified as mansonones E. F and H, respectively. These compounds have originally been isolated from Mansonia altissima Chev, but have never been isolated from Ulmus davidiana Planch. Especially, mansonone H was isolated for the first time from Ulmaceae. The mismatched carbon chemical shifts of mansonones E and F in the reported literature were corrected by the aid of the PFG-HMBC spectral data.

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.327-339
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• 2014

This research includes the identification and cultivation of aerial algae from 33 sites located in Mt. Gwanggyo of Gyeonggi-do, Korea, from March 2011 to August 2012. The ecological factors of aerial algae were analyzed and a total of 29 taxa were identified in 4 phyla, 5 classes, 11 orders, 15 families, 19 genera, 28 species and 1 variety; 12 taxa of cyanophytes, 8 taxa of chrysophytes, and 9 taxa of chlorophytes were found. As for newly recorded cyanophytes of Korea, Komvophoron jovis, Microcoleus steenstrupii, and Nostoc edaphicum appeared. Komvophoron jovis, previously known to grow on rocks and boulders, appeared in soil. Microcoleus steenstrupii, reported to appear in desert soils, appeared on the wet surface of the soil after rain. Nostoc edaphicum, in symbiosis with fungi, appeared on tree bark as the lichen. Thus, there are a total of 99 reported taxa of Korean aerial algae, including 3 species that were discovered in this study.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.48-51
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• 2000

Citrus tristeza virus (CTV) was identified form CTV-infected early satsuma mandarin (Citus unshiu) and yuzu (C.junos) by RT-PCR. The total RNAs were isolated from citrus bark and seaf tissues infected with CTV and reverse transcription was followed with primers designed for amplifying CTV coat protein gene. DNA fragments 738 bp were amplified by RT-PCR and these products were colned for sequence analysis. Based on the sequence analysis, this PCR product has 97% sequence homology to CTV (T-385) CP gene isolated from USA. RT-PCR assay for CTV detection was more sensitivity than ELISA assay which was done with anti-CTV CP antibody. This is the frist report about CTV identification in Cheju island Korea.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.119-122
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• 1995

Neural network has found wide applications in the system identification, modeling, and realization based on its function approximation capability. THe system governe dby nonlinear dynamics is hard to be identified by the neural network because there exist following difficulties. FIrst, the training samples obtained by the stae trajectory are apt to be nonuniform over the region of interest. Second, the system may becomje unstable while attempting to obtain the samples. This paper deals with these problems in discrete-time system and suggest effective solutions which provide stability and uniform sampliing by the virtue of robust control theory and heuristic algorithms.

• Journal of the Korean Wood Science and Technology
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• v.39 no.3
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• pp.213-220
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• 2011

The objective of this study is to conduct the species identification and tree-ring dating for the wood elements of Daesungjeon (main hall) in Jipyeong Hyanggyo, a Confucian shrine in Jije-myeon, Yangpyeong-gun, Gyeonggi-do, Korea. Major wood species for Daesung Hall was Pinus densiflora (88%) belonging to hard pine. The other species was P. koraiensis belonging to soft pine. One large beam and one collar beam with bark were dated to A.D. 1718 and 1720, suggesting either a large-scale repair or moving in 1720s as the record of an historical document 'Hakgyodeongrok'.

• Journal of Plant Biotechnology
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• v.49 no.2
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• pp.139-144
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• 2022

The genus Prunus (family: Rosaceae) consists of over 400 plant species and exhibits vast biodiversity worldwide. Given the wide distribution of this genus, its taxonomic classification is important. Anatomical characteristics are conserved and stable and can therefore be used as an important tool for the taxonomic characterization of plants. Therefore, this study aimed to assess and document the anatomical characteristics of the leaf, stem, and seed of P. africana using micrographs and photographs for possible use in the identification, quality control, and phylogenetic analysis of the species. The anatomical sections of a young stem revealed a cortex consisting of isodiametric parenchyma cells, druse crystals, primary vascular bundles, and pith. The mature stem bark majorly consisted of the rhytidome, with the periderm densely arranged in multiple layers; a cluster of stone cells; and sclerenchyma. The leaf sections were hypostomatic, with stomata sizes ranging from 18.90-(22.34)-26.90 × 15.41-(18.40)-21.22 ㎛. The leaf sections showed the presence of characteristic druse crystals, vascular bundles, and mesophyll layers. The pericarp contained the epicarp, mesocarp, and endocarp, with their thickness being approximately 350-400, 300-350, and 30-50 ㎛, respectively. In addition, it contained a seed testa with a thickness of approximately 50-60 ㎛. The morphological and anatomical characteristics observed in P. africana leaves, stems, and seeds in this study could serve as useful data for the taxonomic identification of this species.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1059-1065
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• 2003

Antimicrobial activity of Mokdan bark (Paeonia suffruticosa $A_{NDR}$) was investigated. Methanol extract of dried Mokdan was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as L. monocytogenes, and E. coli at 500 $\mu\textrm{g}$/disc. Ethylacetate fraction was further fractionated into 3 fractions by silica gel column and thin layer chromatography (TLC). The results showed that ethylacetate fractions No. 1 and 2 had the highest antimicrobial activity. They were mixed again, reseparated, and 3 fractions were obtained. Among them, No. 1 had the highest inhibitory effect on the microorganisms, No. 1 fraction was identified as isobutyl isopentanoate by HPLC, and GC-MS.