• Journal of the Korean Chemical Society
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• v.65 no.6
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• pp.484-488
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• 2021

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.169-172
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• 2006

Sex pheromone blends of large black chafer, Holotrichia parallela (Motschulasky), which consist of a major component L-isoleucine methyl ester (LIME) and a minor component (R)-(-)-linalool, showed different attractiveness depending on the mixing ratios of the two components in potato fields in South Korea. The best ratio for H. parallela attraction was 2.5:1 of LIME and (R)-(-)-linalool. The attraction ability of pheromone traps bated with 2.5:1 ratio did not drop up to 14m, but significantly decreased at 21m from H parallela release point. Korean population of H. parallela showed almost same periodical activity to sex pheromone with that reported in Japan, which showing a circabidian periodicity of 48h cycle.

• Journal of Apiculture
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• v.34 no.3
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• pp.189-195
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• 2019

Plants release a large variety of volatile organic compounds (VOCs) into the surrounding atmosphere. Floral volatile compounds (FVCs) emitted from many plants is the critical factors for pollinator attraction and defense for adaptation in environments. Recent studies indicate that the chemical components contributing to FVCs play an important role in the honeybee attractiveness to flowers. Olfactory signals are rapidly learned, indicating that foraging behavior results from the association of plant chemicals acting as chemosensory cues for the bees. Solid phase microextraction(SPME)-GC/MS method was applied to analyze the chemical composition of FVCs according to the different species of Robinia spp. The abundant compounds identified in R. pseudoacacia were (Z)-β-ocimene (34.86%) and linalool (35.47%). Those of the tetraploid R. pseudoacacia were (Z)-β-ocimene (35.42%) and α-Farnesene (33.94%). The volatiles of R. margarettae 'Pink Cascade' comprised an abundance of (Z)-β-ocimene (42.73%), (E)-4,8-Dimethylnona-1,3,7-triene (37.23%). Differences in FVCs of the different species of Robinia spp. are discussed in light of biochemical constraints on volatile chemical synthesis and of the role of flower scent in ecology of pollination.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.98-104
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• 2009

The objective of this study was to characterize quality changes of PET-packaged green tea beverage during 4-week storage at $60^{\circ}C$. Changes in oxygen transmission of the PET bottle package and cap removal torque were also examined. MXD6 blend PET bottle showed stability in the gas barrier. Its cap removal torque was kept stable during the 4 weeks. pH, color value, contents of vitamin C and catechin showed significant changes during the storage while caffeine and amino acid did not change significantly. Four alcohol flavor components (hexanol, linalool, menthol, and ${\alpha}$-terpineol) increased rapidly during the first three weeks while d-limonene did not show significant change. Sensory test showed decrease in astringent flavor lowering the product flavor and acceptability.

• Journal of Life Science
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• v.5 no.2
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• pp.20-20
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• 1995

The aroma components of commercial green teas picked inAugust were collected and identified. The extract of aroma compounds in green tea were accoimplished by a modified rotary evaporation. The concentrated wxtracts were analyzed and identified by GC and GC-MS. In GC analysis, T$_{R}$ value of GC represented bt KI value which standardized. The most abundant components of green teas picked in August were 1-Penten-3-ol, trans, trans-2, 4-heptadienal, linalool, $\beta$-ionone and nerolidol.

• Journal of Life Science
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• v.5 no.2
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• pp.76-80
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• 1995

The aroma components of commercial green teas picked inAugust were collected and identified. The extract of aroma compounds in green tea were accoimplished by a modified rotary evaporation. The concentrated wxtracts were analyzed and identified by GC and GC-MS. In GC analysis, T$_{R}$ value of GC represented bt KI value which standardized. The most abundant components of green teas picked in August were 1-Penten-3-ol, trans, trans-2, 4-heptadienal, linalool, $\beta$-ionone and nerolidol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.874-880
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• 2006

The volatile compounds of Zingiber officinale Roscoe were extracted by simultaneous steam distillation and extraction (SDE) method and identified with gas chromatigraphy/mass spectrometer (GC/MS) analysis. Enantiomeric compositions of chiral compounds were determined by multidimensional gas chromatography/mass spectrometer (MDGC/MS). A total of 57 compounds were indentified and quantified, including zingiberene, ${\beta}-sesquiphellandrene$, ${\beta}-bisabolene$, $(E,E)-{\alpha}-farnesene$ and ${\alpha}-curcumene$. Among them, zingiberene (38.41%) was founds as the predominantly abundant component. ${\alpha}-Pinene$ and nerolidol in dried ginger were detected by high enantiomeric purity (>96%) for (S)-form, and ${\beta}-pinene$ was detected only (R)-form. The enantiomeric composition of ${\alpha}-terpineol$ revealed 72.0% for (R)-form, and linalool and 4-terpineol showed mixtures of both enantiomers. (S)-Enantiomer was the major enantiomer of limonene having enatiomeric excess of 17.2%. Hence the enantiomeric composition of these compounds can be used as parameter for authenticty control of Zingiber officinale.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.610-616
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• 2002

The growth-inhibiting effects of Pinus densiflpora leaf-derived materials on nine human intestinal bacteria were investigated using the impregnated paper disk method, and their activities were compared with those of 13 commercially available terpenes. The biologically active constituent of the extract of P densiflora leaf was characterized as the monoterpene (1R)-(+)-$\alpha$-pinene by various spectroscopic analyses. Responses varied according to bacterial strain, chemicals, and dose. At 10 mg/disk, limonene and (1R)-(+)-$\alpha$-pinene strongly inhibited the growth of Clostridium perfringens, Staphylococcus aureus, and Escherichia coli, without adverse effects on the growth of five lactic acid-bacteria (Bifidobacterium adolescentis, B. bifidum, B. longum, Lactobacillus acidophilus, and L. casei). Little or no inhibition against seven bacteria was observed with anethole, borneol, camphor, caryophyllene, 1,8-cineole, estragole, linalool, and $\alpha$-terpineol. Structure-activity relationship revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S-(-)-$\alpha$-, and (1S-(-)-$\beta$-pinenes. Furthermore, the growth-inhibition against L. casei was much more pronounced in (1R)-(+)-$\beta$- and (In-(-)-$\beta$-pinenes than (1R)-(+)-$\alpha$- and (1S)-(-)-$\alpha$-pinenes. These results indicate that the (+)-$\alpha$ form seems to be required against C. perfringens and $\beta$ form against L. casei for growth-inhibiting activity. Morphologically, most strains of C. perfringens were damaged and disappeared at 5 and 2 mg/disk of (1R)-(+)-$\alpha$-pinene. Morphological study revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S)-(-)-$\alpha$-, and (1S)-(-)-$\beta$-pinenes. As naturally occurring growth-inhibiting agents, the Pinus leaf-derived materials described above could be useful preventive agents against diseases caused by harmful intestinal bacteria such as clostridia.

• Journal of Applied Biological Chemistry
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• v.53 no.3
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• pp.184-188
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• 2010

Effect of the plant essential oils on the growth of Malassezia pachydermatis was evaluated and the essential oils of Ocimum basilicum L., Melaleuca alternifolia (Maid. & Bet.) Cheel, and Rosa damascene Mill. were the most active against M. pachydermatis and their activity were high than that of itraconazole at 2 mg/mL. The major constituents of the three oils by GC-MS analysis were linalool (21.83%) and estragole (74.29%) for O. basilicum, a-terpinolene (17.96%) and terpinen-4-01 (45.54%) for M. alternifolia, and a-citronellol (59.98%) and geraniol (27.58%) for R. damascene. Results showed that these selected three oils could be effective toward controlling M. pachydermatis opportunistic infections.