• Korean Journal of Medicinal Crop Science
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• v.10 no.3
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• pp.162-166
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• 2002

(Z)-ocimene+limonene, $(E)-{\beta}-ocimene$ and citronellal showed seasonal variation in the leaves of Z. schinifolium. Especially estragole was detected at fruiting stage regardless of collection sites. Common variation components in the leaves of Z. piperitum at all collection sites were (Z)-3-hexenol, ${\alpha}-pinene$, limonene and citronellal. The compositions with monthly variation in Z. schinifolium at arboretum were ${\alpha}-pinene$, myrcene, (Z)-3-hexenyl acetate, ${\alpha}-phellandrene$, (Z)-ocimene+limonene, ${\beta}-phellandrene$, linalool, geranyl acetate while in Z. piperitum were hexanal, (Z)-3-hexenol, (E)-2-hexenal, hexanol, ${\alpha}-pinene$, (Z)-ocimene, limonene, citronellal, geranyl acetate, ${\beta}-caryophyllene$. Estragole was not detected in Z. schinifolium leaves at arboretum due to too young tree to bearing fruit on it.

• Korean Journal of Medicinal Crop Science
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• v.11 no.1
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• pp.40-45
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• 2003

Volatile components in the leaves and fruits of Z. schinjfolium and Z. piperitum were analyzed by Headspace SPME(Solid phase Microextraction). Fifty two and 48 components in the leaves and fruits, repectively, were identified in Z. schinifolium. (E)-2-hexenal, ${\alpha}-pinene$, (Z)-ocimene+limonene, estragole, germacrene-d were detected at common components in the leaves and estragole in the fruits of Z. schinjfolium. Regardless of collection sites hexanal, (Z)-3-hexenol, (E)-2-hexenal, n-hexanol were appeared in the leaves while undecanone in the fruits. Thirty and 27 components in the leaves and fruits, respectively, were identified in Z. piperitum. ${\alpha}-pinene,\;{\beta}-phellandrene$, 1,8-cineole, citronellal and myrcene, (Z)-ocimene+limonene, ${\beta}-phellandrene$ were appeared as common components in the leaves and fruits collected from Baeck-yang-sa and Nae-jang-sa. (Z)-3-hexenol, (E)-2-hexenal, ${\alpha}-pinene\;myrcene\;and\;{\beta}-phellandrene$, citronellal, geranyl acetate were major components in the leaves and fruits from Tong-do-sa.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.284-293
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• 2019

This study investigated the volatile flavor composition of essential oils from Ligularia fischeri and Ligularia fischeri var. spiciformis. The essential oils obtained from the plants were analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). 99.63% volatile flavor compounds were identified in the essential oil from the L. fischeri. The major compounds were (E)-3-hexenol (30.73%), longiverbenone (13.23%), viridiflorol (12.39%), ${\gamma}$-muurolene (7.32%), limonene (6.12%), and caryophyllene (${\beta}-4.24%$). 99.76% volatile flavor compounds were identified in the essential oil from the L. fischeri var. spiciformis. The major compounds were ledol (42.81%), (E)-15-heptadecenoic acid (33.91%), ${\beta}$-bisabolol (3.23%), viridiflorol (3.08%), and cis-${\alpha}$-farnesene (2.60%). Although the two plants are very similar, the chemical composition of the essential oils was significantly different in quality and quantity. In the case of L. fischeri., it has high contents of monoterpene and sesquiterpene. (E)-3-hexenol, longiverbenone, ${\alpha}$-phellandrene, and ${\alpha}$-myrcene were regarded as the characteristic odorants of L. fischeri, but they were not identified in L. fischeri var. spiciformis. Ledo, (E)-15-heptadecenoic acid, and ${\beta}$-bisabolol were regarded as the characteristic odorants of L. fischeri var. spiciformis, but they were not identified in L. fischeri. The ratio of limonene, ${\gamma}$-muurolene and viridiflorol can be used as an indicator to distinguish between these two plants.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.246-254
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• 2007

Fresh tea leaves grown in Jeju Island and Jeonnam Province of South Korea were plucked and processed. Volatile compounds (VCs) were analyzed and identified with SPME-GC/GC-MS/GC-O. The VCs of green teas were classified into two major categories based on their aroma characteristics: the Greenish (Group I), and Floral (Group II) odorants. It was found that the VCs were decreased significantly in fresh tea leaves as they were plucked at the later stages of cultivation. The ratio of VCs responsible for Group I and Group II compounds was well-balanced in tea leaves plucked in May, but the balances were changed when the fresh leaves were processed. The major VCs of fresh tea leaves in Jeju and Jeonnam were n-hexanal, E-2-hexenal, Z-3-hexenal, myrcene, benzyl alcohol, linalool, and phenyl alcohol. Also, Jeju and Jeonnam tea leaves had different aroma composition. n-Heptanol, ${\beta}-pinene$, benzaldehyde, and ethyl salicylate were found in Jeju fresh tea leaves, and Z-3-hexenol, E-2-hexenol, and methyl n-heptanoate were detected in Jeju dry tea leaves. On the other hand, Z-linalool oxide and myrcene were found in Jeonnam dry tea leaves. The SPME-GC method showed high reproducibility (RSD, 7.4%) with no-artifact formation. In this study, optimum plucking period of tea leaves could be determined for production of high quality green tea with a well-balanced aroma and characteristic VCs in green tea according to growing areas.

• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.140-143
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• 2013

We investigated optimal condition for synthesis of (E)-2-hexenyl (E)-2-hexenoate (1) and (E)-2-hexenyl (Z)-3-hexenoate (2), the pheromone components of Riptortus pedestris, by Steglich esterification. The reaction with 1.1-1.5 equivalent of dicyclohexylcarbodiimide (DCC), 1.5-2.0 equivalent of (E)-2-hexenol, and 0.1 equivalent 4-dimethylaminopyrinde (DMAP) to (E)-2-hexenoic acid in toluene or (Z)-3-hexenoic acid in dichloromethane led 1 and 2 in 76-78% and 87-91% yield, respectively.