• Applied Biological Chemistry
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• v.41 no.1
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• pp.95-98
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• 1998

Methanol extracts of 54 plant species in 32 families were tested for their antignawing activities against mice by wire-dipping method. The activity varied with plant species. Potent antignawing activity was observed in extracts from roots of Aucklandia lappa (Compositae), barks of Cinnamomum cassia (Lauraceae), fruits of Illicium verum (Magnoliaeceae), fruits of Piper nigrum (Piperaceae), rhizomes of Rheum officinale (Polygonaceae), and leaves of Pinus densiflora (Pinaceae). As naturally occurring rodent repellents, these plant-derived materials could be useful as a preventive agent against various kinds of damage caused by rodents.

• Journal of Welding and Joining
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• v.33 no.3
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• pp.62-67
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• 2015

A very large shell-structure built in shipyards like ship hulls or offshore structures are joined by welding through full process. As the welding contains a high thermal cycle at a local area, the welded structures should be distorted unavoidably. Because a distorted ship block should be revised to the designed value before the next stage, the ability to predict and to control the weld distortion is an accuracy level of the yard itself. Despite the ship block size, several present thermal distortion methodologies can deal those sizes, but it is a different story to deal full ship size model. Even a fully constructed ship hull not remaining any welding can have an accuracy issue like outfitting installation problems. Any present thermal distortion methodology cannot accept this size for its recommended element size and the number. The ordinary welding breadth at erection stage is about 20~40 mm. It can hardly be a good choice to make finite element model of these sizes considering human effort and computational environment. The finite element model for structure analysis of a ship hull is prepared at front-end engineering design stage which is the first process of the project. The element size of the model is as fine as the longitudinal space, and it is not proper to obtain a weld distortion at the erection stage. In this study, a methodology is suggested that a weldment can be shrunk at original place instead of using structural finite element model. We cut the original shell elements at erection weld-line and put truss elements between the edges of cut elements for weld shrinkage. Additional truss elements are used to facsimile transverse weld shrinkage which cannot be from the weld-line truss element shrink. They attach to weld-line truss element like twigs from barks. The capacity of developed elements is verified through an accuracy check of erection process of a container vessel at the apt. hull. It can be a useful tool for verifying a centering accuracy after renew and for block-separating planning considering accuracy.

• Advances in Traditional Medicine
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• v.4 no.3
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• pp.187-195
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• 2004

A number of plants from different geographical origins have been shown to possess antioxidant activity. Some of them have been developed as natural antioxidant formulations for food, cosmetic and other applications. Bangladeshi flora is a rich source of a range of plant species, many of which are medicinal plants, and have been used in the preparations of the Unani and Ayurvedic traditional medicines. There are no, or just a few, reports on any systematic screening of the extracts of Bangladeshi plants for free radical scavenging activity using DPPH assay available to date. As part of our on-going search for biological activity in Bangladeshi plants, Kadam (Anthocephalus chinensis), Goran (Ceriaps decandra), Swarnalata (Cuscuta reflexa), Gab (Diospyros peregrina), Sundari (Heritiera fomes), Dhundul (Xylocarpus granatum) and Possur (Xylocarpus mekongensis) have been selected for the assessment of their free radical scavenging activity, and studies on the contents of alkaloids, anthraqunones, flavonoids and tannins in these extracts. Most of these species have been used in traditional medicine in Bangladesh and other countries for the treatment of various illnesses ranging from common cold to cancer. All extracts, except the methanol extract of Cuscuta reflexa, displayed significant free radical scavenging activity in the DPPH assay $(RC_{50}$ values within the range of $2.75\;{\times}\;10^{-2}\;to\;4.7\;{\times}\;10^{-3}\;mg/mL)$. Among these extracts, the methanol extract of Xylocarpus granatum exhibited the most potent activity $(4.7\;{\times}\;10^{-3}\;mg/mL)$ and that of Cuscuta reflexa had the least activity $(1.64\;{\times}\;10^{-1}\;mg/mL)$. While none of these plants showed positive tests with Dragendorff's reagent, presence of low to moderate amounts of phenolic compounds, e.g. anthraquinones, flavonoids and tannins was evident in all of these plants, except for the methanolic extracts of C. reflexa and the barks of D. peregrina, which did not display any evidence for the presence of flavonoids and anthraquinones, respectively.

• Natural Product Sciences
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• v.26 no.2
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• pp.144-150
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• 2020

Phytochemical investigation of leaves, barks and roots of Nauclea vanderguchtii led to the isolation of sixteen compounds, which includes one citric acid derivative (2), one alkaloid (16), one peptide derivative (3), and twelve triterpenes (1, 4 - 13). These compounds were identified as rotundanonic acid (1), 2-hydroxy-1,2,3-propanetricarboxylic acid 2-methyl ester (2), asperphenamate (3), lupeol (4), stigmasterol (5), betulin (6), betulenic acid (7), stigmasterol 3-O-β-D-glucopyranoside (8), quinovic acid 3β-O-α-L-rhamnoside (9), α-amyrin (10), 3-oxoquinovic acid (11), ursolic acid (12), hederagenin (13), rotundic acid (14), clethric acid (15), and naucleficine (16) by the analysis of their NMR spectroscopic data including 2D NMR spectra and by comparison of their spectroscopic data reported in the literature. Compounds 1 and 3 were isolated for the first time in the genus Nauclea, and compound 2 was isolated for the first time from the Rubiaceae family. Complete NMR assignations for 1 have been published for the first time.

• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.9-16
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• 1995

Undiluted neoasozin solution (6.5% a.i.), an arsenic fungicide, was sprayed on 169 cankers of apple trees from early March to September in 1987 twice at intervals of one week without scraping off the affected barks. Among the treated cankers, 79.9% ceased to grow within 1∼7 weeks, 13.0% showed partial development, and 7.1% grew continuously to girdle the branches. The partially developed cankers, however, could also be cured by an additional spray after slightly piercing at the edge of cankers to facilitate the penetration of the chemical. When the canker growth was blocked, cankers were encircled by cracks developed at the marginal area of the cankers. If the cracks developed once, very few cankers grew beyond them. The above results suggest that the crack development may be the consequence of the host defense activity to wall off the pathogen. In addition to the curative efficacy, the neoasozin solution inhibited sporulation of the pathogenic fungus almost completely. However, the pathogen survived for more than three months in some cankers that externally appeared to be cured, suggesting that an indirect mode of action of the chemical against apple Valsa canker seems to be still more persuasive than the direct fungicidal effect. In the final examination conducted in the mid April of the next year, 72.7% of the cankers were completely cured by the two successive neoasozin treatments. Moreover the cure rate became 83.1% if that of partially developed cankers which were also completely cured by an additional treatment was also taken into account. Since 1989 when this method was widely applied in apple orchards in Korea, apple Valsa canker has been effectively controlled to reach a tolerable level.

• Natural Product Sciences
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• v.23 no.3
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• pp.151-156
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• 2017

A phytochemical study of Alphonsea cylindrica King (unreported) has led to the isolation of six alkaloids. The compounds were identified as kinabaline (1; azafluorenone alkaloid), muniranine (2), O-methylmoschatoline (3; oxoaporphine alkaloid), lysicamine (4), atherospermidine (5) and N-methylouregidione (6; 4, 5-dioxoaporphine alkaloid). The structures of the isolated compounds were determined based on the spectroscopic techniques and by comparison with data reported in the literature. Alkaloid 2 was isolated as a new derivative of azafluorenone while alkaloids 1, 3 - 6 were isolated for the first time from Alphonsea species. In addition, alkaloid 3 and 4 showed inhibition zone against Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus cereus in disc diffusion test. The minimum inhibition concentration (MIC) values of lysicamine (4) against S. aureus, B. cereus and P. aeruginosa were found to be smaller than O-methylmoschatoline (3). Therefore, the reported antibacterial activity showed the potential of this plant as natural antibacterial agent and supported the documented traditional use of Alphonsea sp. in the treatment of diarrhea and fever.

• Journal of the Korean Wood Science and Technology
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• v.26 no.1
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• pp.7-13
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• 1998

In order to reconstruct the traditional technology of Korean golden varnish(Hwangchil) made from the exudates of D. morbifera, this study in the second step was carried out to analyze the chemical composition and oil properties of the exudates for coatings and bark extractives made from the trees of D. morbifera more than 20 years old grown in Wando and Jejudo islands in the southwestern part of Korean peninsula according to the physiological seasons. The results obtained are as follows: 1. The exudates appeared to be a phytoalexin because it exudated after several days in tapping only in summer season. 2. Both the exudates and bark-extracts with acetone contained 50~60% unsaponifiables and 30~50% saponifiables 3. A major component of essential oil in bark-extractives was ${\beta}$-cubebene and reached to 60~80%, while that of exudates included only 34% ${\beta}$-cubebene and some other compounds such as ${\beta}$-cadinene of 12%, aromadendrene of 9%, ${\beta}$-selinene of 9%, CAS030021-74-0 of 10%, etc. in GC-MS spectrometer. 4. A mjor component of fatty oil fraction in bark-extractives was linoleic acid and reached to more than 60%, while the exudates had mostly other components such as terpenes and phenolics instead of fatty acids accordint to GC-MS spectrometer. 5. Iodine value of samples after oil refining had 214mg/g in the exudates and more than than 150mg/g in bark-extractives, so the latter belonged to a drying oil.. 6. Therefore, the exudates from D. morbifera for traditional Korean golden varnish seems to have beeen used to a good varnish because it has some specific compounds different from its bark-extractives or general varnishes.

• Korean Journal of Pharmacognosy
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• v.39 no.1
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• pp.68-73
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• 2008

The present study represents the screening of the protective effects of herbal methanolic extracts from Baekdu mountain against tacrine-induced cytotoxicity in HepG2 cells. Tacrine is an acetylcholinesterase inhibitor, and used for the treatment of Alzheimer's disease. However, administration of tacrine for the treatment of Alzheimer's disease results in a reversible hepatotoxicity in 30-50% of patients, consequently limiting clinical use. Therefore, studies for natural products with protective effect on the tacrine-induced hepatotoxicity would be valuable as providing potential therapeutic use. 109 plant sources were collected in Baekdu mountain, and extracted with methanol. These extracts had been screened the protective effects against tacrine-induced cytotoxicity in HepG2 cells at the 100 and 300 ${\mu}g/ml$. Of these, ten methanolic extracts, roots of Ampelosis japonica, aerial parts of Berberis amurensis, aerial parts of Sedum aizoon, aerial parts of Lespedeza tomentosa, aerial parts of Lespedeza juncea, aerial parts of Hypenricum ascyron, stem barks of Syringa reticulata, fruits of Gleditsia japonica, aerial parts of Chamaenerion angustifolium, branches of Ginkgo biloba, showed significant protective effects against tacrine-induced cytotoxicity in HepG2 cells.

• Journal of the Korean Wood Science and Technology
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• v.24 no.2
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• pp.46-54
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• 1996

This study was carried out to investigate the vacuum drying characteristics of 50mm- and 75mm- thick tree disks of some domestic softwoods for substituting the conventional hardwoods as the materials for wood crafts. Though the elapsed drying times from green to in-use moisture content(MC) were largely shortened by vacuum drying, the tree disks treated by EWS couldn't be dried to in-use MC, and so sapwood stains also were occurred severely. We suggest EWS treatment is undesirable for the species with very high sapwood portion or vacuum drying with hot water circulation heating system. Heart checks were slight, but sapwood checks, which have never been trouble in drying process of tree disks, were severe. For the reasonable explanation it is suggested MC differences between sapwood and heartwood were large and most of tree disks had already no barks before drying test. Ginkgo was vacuum-dried with very slight drying defects such as heart checks, sapwood checks. V-cracks and sapwood stains. In Korean red pine and pitch pine V-cracks were severely occurred. And it was found the special feature that most of these defected tree disks contained several V-cracks within one tree disk. It can be considered as the causes that the region of sapwood was defected by the several checks at the early drying stage because of the steep MC gradient along the radial direction, and then at the later drying stage the drying stresses due to differential shrinkage were concentrated on these brittle spots.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.545-551
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• 1994

Ethanol extract of barks, roots, stems, leaves and seeds of 49 species of plants were examined their growth inhibition by disk method on Listeria monocytogenes ATCC 19111, ATCC 19112, ATCC 19113, ATCC 19114 and ATCC 15313. The extracts exhibited comparatively strong growth inhibition were compared their activity with broth culture containing different concentration of the extracts. L. monocytogenes ATCC 19111 was inhibited by Siegesbeckia pubescens Makino and Morus alba Linne (Ma) extracts. L. monocytogenes ATCC 19112 and ATCC 19114 were inhibited by Ma extract. ATCC 19113 was inhibited by Sophora flavescens AITON and Ma extract. ATCC 15313 was inhibited by Foeniculum vulgare Gaertner, Prunella vulgaris Var lilacina Nakai and Ma extract. Ma extract showed comparatively good inhibition effect for 5 strains of L. monoytogenes. 500 ppm of Ma extract almost inhibited the growth of all L. monocytogenes tested.