• KSBB Journal
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• v.27 no.3
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• pp.157-160
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• 2012

When iron oxide magnetic nanoparticles were synthesized by co-precipitation method using aqueous ammonia as reducing agent, the synthesized particles were aggregated and thus precipitation occurred. Using Magnolia kobus leaf extract as reducing agent, spherical nanoparticles of 50~200 nm were synthesized with low yield. By using both Magnolia kobus leaf extract and aqueous ammonia as reducing and stabilizing agents, smaller nanoparticles of 40~120 nm could be synthesized with various shapes. The synthesized magnetic nanoparticles were characterized with field emission transmission electron microscopy (FE-TEM) and scanning electron microscopy (SEM). TEM and SEM images showed that the magnetic nanoparticles are a mixture of triangles, tetragons, rods and spherical structures.

• The Korean Journal of Mycology
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• v.50 no.2
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• pp.125-130
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• 2022

The powdery mildew found on Magnolia kobus was recorded as Microsphaera alni for the first time in Korea in 1975. After splitting M. alni into several distinct species, this mildew was regarded as Microsphaera magnifica, now Erysiphe magnifica. Since E. magnifica is known to be a North American species, the powdery mildew found on M. kobus in Korea was studied to clarify its identity. Based on morphological characteristics and sequencing results of the internal transcribed spacer and large subunit rDNA gene, the powdery mildew found on M. kobus in Korea was identified as Erysiphe magnoliicola.

• Journal of the Korean Wood Science and Technology
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• v.26 no.4
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• pp.61-70
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• 1998

Xylem, bark and flower buds of Magnolia kobus DC. var. borealis Sarg. were extracted with ethanol. And then the ethanol extracts were fractionated with diethyl ether. The lignans structure of the diethyl ether fractions were determined by spectroscopic methods. The results are summarized as follows : 1. Three compounds, aschantinn(X-I), yangambin(X-II), (-)syringaresinol(X-III), tetrahydrofurofuranoid lignans were isolated from the xylem. 2. Five compounds were isolated from the bark. These are all tetrahydrofurofuranoid lignans, aschantin(B-I), yangambin(B-II), medioresinol(B-III), (+)syringaresinol(B-IV), and tetrahydrofuranoid, kobusinol B(B-V). 3. Three tetrahydrofurofuranoid lignans, kobusin(F-I), aschantin(F-II), yangambin(F-III) were isolated from the flower buds. 4. Isolated lignans from the each tissue were two types of tetrahydrofurofuran type and tetrahydrofuran type. 5. The tetrahydrofurofuranoid lignans were five compounds such as kobusin, aschantin, yangambin, medioresinol, and syringaresinol, while the tetrahydrofuranoid lignans was kobusinol B. 6. Most of these lignans were substituted with the methylenedioxy or methoxyl groups.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1114-1118
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• 2006

(+)-Eudesmin [4,8-bis(3,4-dimethoxyphenyl)-3,7 -dioxabicyclo[3.3.0]octane] was isolated from the stem bark of Magnolia kobus DC. var. borealis Sarg. and found to have neuritogenic activity. $50\;{\mu}M$ (+)-eudesmin induced neurite outgrowth and enhanced nerve growth factor (NGF)-mediated neurite outgrowth from PC12 cells. At this concentration, (+)-eudesmin also enhanced NGF-induced neurite-bearing activity and this activity was partially blocked by various protein kinase inhibitors. These included PD98059, a mitogen-activated protein kinase (MAPK) kinase inhibitor. GF109203X, a protein kinase C (PKC) inhibitor and H89, a protein kinase A (PKA) inhibitor. These results suggest that (+)-eudesmin can induce neurite outgrowth from PC12 cells by stimulating up-stream MAPK, PKC and PKA pathways.

• Journal of the Korean Wood Science and Technology
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• v.27 no.1
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• pp.105-114
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• 1999

Antimicrobial activities of the organosoluble extracts, seperated fractions and isolated lignans from the leaves tissue of Magnolia kobus DC. var. borealis Sarg. were investigated. The results are summarized as follows : 1. The inhibitory components against the spore growing test were concentrated on light petroleum ether and diethyl ether soluble fractions. The light petroleum ether solubles of the leaves tissue had terpenes compound, so, that they caused growing inhibition. These appearance showed high values of Rf on TLC bioautography and GC analyses with monoterpenes. 2. In the lignans, syringaresinol(X III), medioresinol(VI), phillygenin(VIII), kobusinol A(X) showed relatively high inhibitory effects in the spore growing test, and these are all showed structural characteristic of the phenolic hydroxyl group of guaiacyl and syringyl skelecton. 3. The light petroleum ether soluble fraction showed the strongest inhibitory effect against the antimicrobial activity in the seperated fractions. 4. The inhibitory effects of the lignans against the bacteria showed not so pronounced independantly, but the extracts and separated fractions contained with these lignans showed something synergism.

• Journal of Life Science
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• v.30 no.3
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• pp.278-284
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• 2020

Magnolia kobus is known to exert various biological effects, such as antioxidant and hypnotic activity. In this study, we investigated the antimicrobial and anti-inflammatory activity of M. kobus essential oil extracted using steam distillation. Its antimicrobial activity was tested against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa by the paper disk diffusion and minimum inhibitory concentration (MIC) methods. Its anti-inflammatory activity was evaluated by measuring its inhibition ratio on the production of nitric oxide (NO) and PGE₂ in lipopolysaccharide (LPS)-induced RAW264.7 cells. Its composition was analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that M. kobus essential oil exhibited excellent antibacterial activity against S. aureus, with a clear zone of 18 mm and an MIC value of 0.25 mg/ml. Its clear zones against P. aeruginosa and E. coli were 14 mm and 17 mm, respectively, while its MIC values were 1 mg/ml and 0.5 mg/ml, respectively. The essential oil exhibited no cytotoxicity to the RAW264.7 cells at a concentration of 500 ㎍/ml while showing NO (37.7%) and PGE₂ inhibition (24.0%). Its three main fragrance ingredients identified were 3-carene (77.07%), β-elemene (6.92%), and caryphyllene (2.86%). The results suggest that M. kobus essential oil has potential as a cosmetic functional material with antimicrobial and anti-inflammatory effects.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.1087-1090
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• 2009

This study was carried out to research antimicrobial agents from medicinal plants, Glycyrrhiza uralensis, Dryopteris crassirhizoma, Dictamnus albus, Paeonia lactiflora, Angelica dahurica, Spirodela polyrhiza, Cimicifuga heracleifolia, Bupleurum falcatum, Magnolia kobus, Artemisia princeps, Arctium lappa, Aster tataricus, Hovenia dulcis, Citrus unshiu, Asparagus cochinchinensis, Gardenia jasminoides, Smilax china, Hovenia dulcis, Prunus sargentii, Scutellaria baicalensis. The ethanol extracts of 20 medicinal plants were tested for the antimicrobial activity against Agrobacterium tumefaciens. The extracts of Glycyrrhiza uralensis, Dryopteris crassirhizoma, Cimicifuga heracleifolia, Bupleurum falcatum showed antimicrobial activities against Agrobacterium tumefaciens.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.123-123
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• 2004

• Korean Chemical Engineering Research
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• v.48 no.1
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• pp.98-102
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• 2010

Magnolia kobus leaf extract was used for the synthesis of bimetallic Au core-Ag shell nanoparticles. Gold seeds and silver shells were formed by first treating aqueous solution of $HAuCl_4$ and then $AgNO_3$ with the plant leaf extract as reducing agent. UV-visible spectroscopy was monitored as a function of reaction time to follow the formation of bimetallic nanoparticles. The synthesized bimetallic nanoparticles were characterized with transmission electron microscopy(TEM), energy dispersive X-ray spectroscopy(EDS), and X-ray photoelectron spectroscopy(XPS). TEM images showed that the bimetallic nanoparticles are a mixture of plate(triangles, pentagons, and hexagons) and spherical structures. The atomic Ag contents of the bimetallic Au/Ag nanoparticles determined from EDS and XPS analysis were 34 and 65 wt%, respectively, suggesting the formation of bimetallic Au core-Ag shell nanostructure. This core-shell type nanostructure is expected to have potential for application in surface enhanced Raman spectroscopy and in the sensitive detection of biomolecules.

• Journal of Korean Society of Forest Science
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• v.26 no.1
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• pp.49-55
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• 1975

This study was carried out to find out the proper method of grafting of Magnolia grandiflora L. Magnolia kobus DC. was used as stocks and the modified veneer grafting method in which a flap was attached to the cut surface of scion was adopted. And also the environment of the grafting beds was controlled for giving optimum humidity (90-100%) and temperature ($20-25^{\circ}C$). The results are summarized as follows: 1. Two year-old seedlings of M. kobus were best as stocks for grafting of M. gantiflora. 2. The modified veneer grafting which brought the successful result of 43 to 89.5 percent found to be very efficient method. 3. The environmental control made of vinyl tunnel and screen (lath) was very effective to attain to the excellent result of 89 percent. 4. For scions, one to two year-old branches with well developed winter buds collected just before the time of grafting gave the best results. 5. The optimum season for grafting in Kwangju districts was 15 to 20, April.