• The Plant Pathology Journal
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• v.23 no.2
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• pp.97-102
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• 2007

A total of 39 essential oils were tested for antifungal activities as volatile compounds against five phytopathogenic fungi at a dose of 1 ${\mu}l$ per plate. Five essential oils showed inhibitory activities against mycelial growth of at least one phytopathogenic fungus. Origanum vulgare essential oil inhibited mycelial growth of all of the five fungi tested. Both Cuminum cyminum and Eucalyptus citriodora oils displayed in vitro antifungal activities against four phytopathogenic fungi except for Colletotrichum gloeosporioides. The essential oil of Thymus vulgaris suppressed the mycelial growth of C. gloeosporioides, Fusarium oxysporum and Rhizoctonia solani and that of Cymbopogon citratus was active to only F. oxysporum. The chemical compositions of the five active essential oils were determined by gas chromatography-mass spectrometry. This study suggests that both E. citriodora and C. cyminum oils have a potential as antifungal preservatives for the control of storage diseases of various crops.

• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.148-154
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• 2007

Volatile components of the essential oils of Satsuma mandarin (C. unshiu), Dangyuza (C. grandis), Yuza (C. junos), Byungkyul (C. playtymamma), Jinkyul (C. sunki), and Hakyul (C. natsudaidai) grown in Jeju Island were isolated from the fruit peels by hydro distillation and determined by GC-MS. GC-MS analysis identified 58 compounds, with main components being d-limonene $(64.01{\sim}79.34%),\;{\beta}-myrcene\;(3.01{\sim}26.53%),\;{\gamma}-terpinene\;(0.11{\sim}12.88%),\;{\beta}-pinene\;(0.78{\sim}4.74%),\;and\;{\alpha}-pinene\;(1.01{\sim}2.55%)$. Differences in compositions and contents of the essential oils were observed among citrus varieties. Effects of citrus oils on growth inhibitions of Escherchia coli, Staphyllococcus epidermidis, and Candida albicans were investigated using disc diffusion assay and minimal inhibitory concentration (MIC) assay. The essential oils inhibited growths of the test organisms, exhibiting higher levels of activity against Gram-positive S. epidermidis (MIC values $0.04{\sim}0.17mg/mL$), whereas Gram-negative E. coli was moderately resistant (MIC values $1.66{\sim}20.30mg/mL$). MIC of citrus essential oils ranged from $0.82{\sim}23.69mg/mL$ against C. albicans. The essential oils obtained from C. sunki, C. grandis, and C. playtymamma showed the highest antimicrobial activities against S. epidermidis and C. albicans, indicating their potential as natural antimicrobial agents.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.36-43
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• 2006

Using fluidized bed type fast pyrolysis system (capacity 400 g/h) bio-oils were produced from beech (Fagus sylvatica) and softwood mixture (spruce and larch, 50:50). The pyrolysis was performed for 1~2 s at the temperature of $470{\pm}5^{\circ}C$. Pyrolysis products consisted of liquid form of bio-oil, char and gases. In beech wood bio-oil was formed to ca. 60% based on dry biomass weight and the yield of bio-oil was 49% in soft wood mixture. The moisture contents in both bio-oils were ranged between 17% and 22% and the bio-oil's density was measured to $1.2kg/{\ell}$. Bio-oils were composed of 45% carbon, 47% oxygen, 7% hydrogen and lower than 1% nitrogen,which was very similar to those of original biomass. In comparison with oils from fossil resources, oxygen content was very high in bio-oils, while no sulfur was found. More than 90 low molecular weight components, classified to aromatic and non aromatic compounds, were identified in bio-oils by gas chromatographic analysis, which amounted to 31~33% based on the dry weight of bio-oils.

• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.164-169
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• 2007

Three coniferous essential oils were extracted from Abies koreana, Cryptomeria japonica, and Torreya nucifera by hydrodistillation. The chemical composition of each oil was analyzed by GCMS, and their antimicrobial activities were tested against two bacteria and one yeast strains. Fortyseven compounds were identified from A. koreana oil, 39 from C. japonica, and 59 from T. nucifera. Main components of the essential oils were limonene (23.5%), bornyl acetate (17.9%), ${\alpha}-pinene$ (11.1%), and camphene (10.2%) in A. koreana, kaurene (26.3%), ${\gamma}-eudesmol$ (19.0%), elemol (6.9%), and sabinene (5.1%) in C. japonica, limonene (13.5%), ${\delta}-cadinene$ (10.5%), ${\alpha}-bisabolol$ (10.2%), and ${\alpha}-copaene$ (7.7%) in T. nucifera. Among the three coniferous trees tested, the essential oils of A. koreana exhibited higher and broader antimicrobial activity against the tested organisms than those of C. japonica and T. nucifera.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.631-634
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• 2004

The oils of Acorus gramineus, Cinnamomum sieboldii, Eugenia aromatica, and Inula helenium were tested for their acaricidal activity against Dermatophagoides farinae and D. pteronyssinus. Responses varied according to dose and mite species. As compared to the oils, the oil most toxic to D. farinae and D. pteronyssinus was E. aromatica, followed by C. sieboldii, A. gramineus, and I. helenium. On the basis of $LD_{50}$ values of the oils in A. gramineus, C. sieboldii, and E. aromatica, the compound most toxic against D. farinae and D. pteronyssinus was eugenol congeners (isoeugenol>eugenol>acetyleugenol) followed by benzyl benzoate, salicylaldehyde, safro1, DEET, cinnamyl alcohol, and 3-carene. As a naturally occurring acaricide, these oils and eugenol congeners could be useful as new acaricidal agents against Dermatophagoides spp.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.367-371
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• 2004

Bio-degradable hydraulic oil using polyolester base oil is formulated for the applications of heavy duty hydraulic machineries. It has proved quality and market price competitiveness by assessment of reliability test in vehicle manufacturer and specific vehicle related institute. Contribution of bio-degradable oil keep the working environment clean and increase export competitiveness in European market. Leakage or waste of mineral types of hydraulic oils in heavy duty machineries causes pollution of river, ocean, underground water. Drinkable-water pollution is serious problem in Europe. In some European countries, using bio-degradable hydraulic oils become an obligation in heavy duty machineries. New product of bio-degradable oils satisfy the European regulations(OECD 302B) and shows excellent performance in compare with European products.

• Natural Product Sciences
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• v.26 no.1
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• pp.97-107
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• 2020

Isolation of oils from leaves of Juniperus phoenicea and Juniperus oxycedrus was obtained by steam distillation extraction method. The compositions of essential oils (EOs) were studied by means of GC-MS and GC-FID, using the internal standard method and relative response factors. Around ninety eight compounds were determined in total, representing 98.25 g/100 g of EO of J. phoenicea and 98.48 g/100 g of EO of J. oxycedrus, respectively. The volatile leaf oils were dominated by the terpenic hydrocarbon fractions (79.87 g/100 g) and (61.27 g/100 g) characterized by high contents of α-pinene (64.6 g/100 g) and (54.0 g/100 g) in J. phoenicea and J. oxycedrus, respectively, as the main component. Also, the enantiomeric distribution of α-pinene, sabinene, camphene, δ-3-carene, β-pinene, limonene, linalool, terpinen-4-ol, bornyl acetate, and borneol in both oils is presented for the first time.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.113-114
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• 2016

In this study, various fats and oils were soaked in low-strength mortar to experiment what kind of fats and oils had the worst effect on low-strength mortar; it went as follows. For rate of change in length of fat and oil soaking, there was an increase in the order of pig fat, bio-diesel, grape seed oil, and water; in the case of olive oil it was destroyed within 56 days. For rate of change in mass, there was an increase in the order of bio-diesel, water, pig fat, grape seed oil, and olive oil. For relative motion elastic coefficient, there was a decrease in the order of olive oil, grape seed oil, and water. On the whole, pig fat, bio-diesel, and olive oil were shown to have the worst effect on low-strength mortar.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1568-1572
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• 2007

To develop a natural fungicide against Botrytis cinerea and Colletotrichum gloeosporioides, a total of 25 essential oils were tested for their fumigant activity against post-harvest pathogens. The vaporous phases of oils were treated to each fungus on potato dextrose agar medium in half-plate separated Petri plates at $10\;{\mu}g$ per plate. The essential oil of Illicium verum strongly inhibited the mycelial growth of both B. cinerea and C. gloeosporioides by over 90%. On the other hand, the essential oil of Schizonepeta tenuifolia showed inhibitory activity against mycelial growth of only B. cinerea by over 90%. Gas chromatography-mass spectrometry and bioassay indicated trans-anethole in I. verum and menthone in S. tenuifolia as a major antifungal constituent. The essential oils of I. verum and S. tenuifolia and their major constituents could be used to manage post-harvest diseases caused by B. cinerea and C. gloeosporioides.

• Journal of the Korean Wood Science and Technology
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• v.47 no.3
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• pp.344-359
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• 2019

Effects of various types of zeolite on the catalytic performance of hydrodeoxygenation (HDO) of bio-oil obtained from waste larch wood pyrolysis were investigated herein. Bifunctional catalysts were prepared via wet impregnation. The catalysts were characterized through XRD, BET, and SEM. Experimental results demonstrated that HDO enhanced the fuel properties of waste wood bio-oil, such as higher heating values (HHV) (20.4-28.3 MJ/kg) than bio-oil (13.7 MJ/kg). Water content (from 19.3 in bio-oil to 3.1-16.6 wt% in heavy oils), the total acid number (from 150 in bio-oil to 28-77 mg KOH/g oil in heavy oils), and viscosity (from 103 in bio-oil to $40-69mm^2/s$ in heavy oils) also improved post HDO. In our experiments, depending on the zeolite support, NiFe/HBeta exhibited a high Si/Al ratio of 38 with a high specific surface area ($545.1m^2/g$), and, based on the yield of heavy oil (18.3-18.9 wt%) and HHV (22.4-25.2 MJ/kg), its performance was not significantly affected by temperature and solvent concentration variations. In contrast, NiFe/zeolite Y, which had a low Si/Al ratio of 5.2, exhibited the highest improved quality for heavy oil at high temperature, with an HHV of 28.3 MJ/kg at $350^{\circ}C$ with 25 wt% of solvent.