• Journal of Applied Biological Chemistry
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• v.62 no.1
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• pp.7-10
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• 2019

The whole plants of Loranthus tanakae were repeatedly extracted with 80% aqueous MeOH and the concentrate was partitioned into ethyl acetate (EtOAc), n-butyl alcohol (n-BuOH) and $H_2O$ fractions. The repeated silica gel ($SiO_2$), octadecyl $SiO_2$ (ODS), and Sephadex LH-20 column chromatographies for the n-BuOH fraction led to isolation of a cyclofarnesane sesquiterpene glucoside. The chemical structure including stereo structure was determined to be a (1'R,3'S,5'R,8'S,2E,4E)-dihydrophaseic acid $3^{\prime}-O-{\beta}-{\text\tiny{D}}$-glucopyranoside on the basis of spectroscopic analyses. This compound was isolated for the first time from L. tanakae in this study. Compound 1 showed a moderate dose-dependent cytotoxicity against human Caucasian gastric adenocarcinoma cells and human hepatocyte cari-noma cells cell lines at higher than $50{\mu}g/mL$.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.490-501
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• 2022

In this study, the isoprene and terpene emissions from 32 major urban tree species were investigated. We conducted sampling using a dynamic enclosure system between June and July 2021. Seedlings aged < three years were enclosed in a chamber consisting of a 400 L transparent Tedlar bag. The air flow from the outlet of the chamber was sampled using Tenax-filled sorbent tubes under standard conditions (temperature: 30°C; PAR: 1,000 μmol/m²/sec). A thermal desorption gas chromatography/mass spectrometry system was used to analyze the following 38 biogenic volatile organic compounds: isoprene, monoterpenes, sesquiterpenes, oxygenated monoterpenes, and oxygenated sesquiterpenes. Isoprene emitters included Quercus mongolica, Salix koreensis, Robinia pseudoacacia, and Salix chaenomeloides. Monoterpene emitters included Pinus strobus, Cedrela sinensis, and Cercis chinensis. The monoterpene emission profiles were dominated by á-pinene, myrcene, camphene, and limonene. The predominant oxygenated monoterpene and oxygenated sesquiterpene were eucalyptol and caryophyllene oxide, respectively. For all species, the contributions of sesquiterpenes and oxygenated sesquiterpenes were relatively low.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.6
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• pp.521-531
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• 2023

Transmembrane protein TMEM16A, which encodes calcium-activated chloride channel has been implicated in tumorigenesis. Overexpression of TMEM16A is associated with poor prognosis and low overall survival in multiple cancers including lung adenocarcinoma, making it a promising biomarker and therapeutic target. In this study, three structure-related sesquiterpene lactones (mecheliolide, costunolide and dehydrocostus lactone) were extracted from the traditional Chinese medicine Aucklandiae Radix and identified as novel TMEM16A inhibitors with comparable inhibitory effects. Their effects on the proliferation and migration of lung adenocarcinoma cells were examined. Whole-cell patch clamp experiments showed that these sesquiterpene lactones potently inhibited recombinant TMEM16A currents in a concentration-dependent manner. The half-maximal concentration (IC50) values for three tested sesquiterpene lactones were 29.9 ± 1.1 µM, 19.7 ± 0.4 µM, and 24.5 ± 2.1 µM, while the maximal effect (E_max) values were 100.0% ± 2.8%, 85.8% ± 0.9%, and 88.3% ± 4.6%, respectively. These sesquiterpene lactones also significantly inhibited the endogenous TMEM16A currents and proliferation, and migration of LA795 lung cancer cells. These results demonstrate that mecheliolide, costunolide and dehydrocostus lactone are novel TMEM16A inhibitors and potential candidates for lung adenocarcinoma therapy.

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.185.2-185.2
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• 2001

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.409-414
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• 2012

Xanthorrhizol is a bisabolane type of natural sesquiterpene, the major component of essential oils of Curcuma xanthorrhiza. 2-(3-Methoxy-4-methylphenyl)propan-1-ol and 2-(3-hydroxy-4-methyl phenyl)propan-1-ol could be essential building block for enantioselective synthesis of xanthorrhizol. Enantioselective (c = 53%, E = $80{\pm}3$) for R-(+)-2-(3-hydroxy-4-methylphenyl) propan-1-ol and (c = 58%, E = $27{\pm}1$) for R-(+)-2-(3-methoxy-4-methylphenyl) propan-1-ol resolution processes were developed via lipase-catalyzed reaction. We found lipase Aspergillus oryzae (AOL) and Porcine pancreas (PPL) are selective to transesterification and hydrolysis in organic and aqueous phase. Modified demethylated substrate is appropriate for enantioselective hydrolysis reaction without any additives. Enantiopure chiral alcohol was crystallized from ethyl acetate/n-hexane co-solvent system. Gram scale resolved chiral intermediate will facilitate the synthesis of the unnatural S-(+)-xanthorrhizol, the corresponding isomer of the natural one.

• Analytical Science and Technology
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• v.9 no.1
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• pp.107-111
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• 1996

A phytotoxic compound was isolated from a culture of Bipolaris cynodontis, a fungus pathogenic to Bermuda grass. The structure was determined by spectroscopic analyses including 2D NMR experiments, to be sesquiterpene having a 9-carbon unit side chain. The compound inhibits the root growth of the seedlings of Italian ryegrass and rice plant, the host plant of the B. cynodontis, by about 100% at 100ppm, and it is suggested that this may play an important role in the expression of the disease symptom.

• Food Quality and Culture
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• v.1 no.1
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• pp.13-17
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• 2007

The volatile flavor compounds of Saussurea lappa C.B. Clarke, a perennial, aromatic and medicinal herbaceous plant of the Asteraceae family, were isolated by the hydro distillation extraction method using a Clevenger-type apparatus, and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The plant yielded a light yellow colored oil (0.02%, v/w). From S. lappa C.B. Clarke root oil, sixty-three volatile flavor compounds were tentatively identified, among which sesquiterpene was predominant (21.70%). The identified compounds of the root oil constituted 87.47% of the total peak area. From the constituents making up more than 5% of the volatile flavor components, a long-chain aldehyde, (7Z, 10Z, 13Z)-7, 10, 13-hexadecatrienal, was the most abundant volatile flavor compound (21.20%), followed by dehydrocostuslactone (10.30%) belonging to sesquiterpene lactone, valerenol (5.30%) and vulgarol B (5.06%).

• Natural Product Sciences
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• v.10 no.2
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• pp.69-73
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• 2004

Continuation of a phytochemical study of Cichorium intybus L. (Astraceae) growing in Egypt, resulted in the isolation and identification of a new sesquiterpene lactone 3,4-dihydrolactucin, in addition to the eight known compounds; kaempferol, isoscutellarin, cichoriin, umbelliferone, lupeol, lupeol acetate, ${\beta}-sitosterol$, and ${\beta}-sitosterol-3-O-glucoside$. Chemical structures of the isolated compounds were assigned based on different physical, chemical, and spectroscopic techniques including IR, UV, MS, 1D- and 2D-NMR spectra. Furthermore, the antimicrobial, and spasmogenic activities of some fractions and isolates were also assessed.

• Biomolecules & Therapeutics
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• v.8 no.1
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• pp.22-26
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• 2000

In order to study the cytotoxic properties of sesquitepenes, dehydrocostus lactone (DL) and costunolide from Saussurea lappa, cytotoxicity was measured by SRB method using various human cancer cell lines. Dehydrocostus lactone(DL) and costunolide exhibited significant cytotoxicity against A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT 15 cells. The U937 human leukemia cells treated with DL showed several apoptotic evidences like chromosome condensation and formation of apoptotic bodies. From the results of FACS analysis, early apoptosis was observed by phosphatidylserine externalization detected by annexin V-FITC. Furethermore, these studies determined hypodiploid contents and effects on the cell phase distribution of DL-treated U937 cells. After exposure of U937 cells to $30\mu\textrm{M}$ DL effectively led to G2/M modified cell cycle distribution within 24hr. These observations suggest that DL can be used efficiently for the cancer treatment.

• Analytical Science and Technology
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• v.9 no.4
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• pp.331-335
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• 1996

Flavor constituents of green tea flower produced in Korea were analyzed by gas chromatography and mass spectrometry. 56 compounds in sample were separated and indentified as 22 hydrocarbons, 14 alcohols, 6 aldehydes, 5 esters, and 9 others. Higher concentrated substances were heneicosyl formate, ${\alpha}$-phenyl ethyl alcohol, and acetophenone. Germacrene D as a sesquiterpene were also identified.