• Proceedings of the Korean Society of Applied Pharmacology
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• 2000.04a
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• pp.10-14
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• 2000

The cycloooxygenase enzymes catalyze the oxidative conversion of arachidonic acid into prostag1andin H$_2$Which mediates both benificial and pathological effects. The COX-1 is constitutively expressed in most tissues and in blood platelets wherease the expression of COX-2 isoform is induced in response to inflmmatory stimuli such as cyctokynes. Thus the identification of a novel COX-2 selective inhibitor should offer excellent antiinflammatory activity with minimal side effects such as gastrointestinal toxicity. Recently, a group of structurally unique and biologically active pimarane diterpenoids has been isolated from indigenous Korean medicinal plants. These new diterpenoids turned out to be potential analgesic and antiinflammatory agent due to their potent inhibitory activities of prostaglandin synthesis. We have also found that the inhibition of PGE$_2$synthesis is attributed to the potent COX inhibition by pimarane diterpenoid in arachidonic acid cascade. In conjunction with development of new analgesic and nonsteroidal antiinflammatory agent, a series of works on these diterpenoids have been extensively carried out in our laboratories. These efforts involve the structure-activity relationship of pimaradienoic acid, molecular modelings and COX inibitory activities as well as actiinflammatory effects of its structural analogues. In addition, the total syntheses of the new natural pimarane diterpenoids, their stereoisomers and other structural variants were intensively investigated.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.159-160
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• 1998

Results of chemistry and biological activity of many years indicate that plants belonging to the Isodon genus are rich in ent-kaurane diterpenoids, which have been revealed to possess biological activities such as antitumor, antibacterial and antiinflammatory effects. In continuation of our research on diterpenoids in medicinal plants of this genus, the acetone extract from the leaves of I. xerophilus, which is a plant native to Yunnan province of China, showed potent antitumor activity against K562. After partition, the most active EtOAc part was studied. Four new diterpenoids named xerophilusin A(l), B(2), C(3), D(4), and eight known compounds including macrocalin B(5) and rabdorosthomin A(6) were isolated, whose structures were elucidated through a series of one- and two-dimensional NMR techniques(DEPT, COSY, HMQC, HMBC and ROESY experiments). Among them, compound 1, 2 and 5 had two unique epoxy units formed by two ether bridges from C-20 to C-7, C-14. Up to now, there are four compounds having such an peculiar structure besides these three compounds. Compound 3 and 4 were two of the few examples possessing $1{\beta}$ substitutes. All the diterpenoid compounds were subjected to the antitumor screening. It is interesting that only xerophilusin A(l), B(2) and macrocalin(5) exhibited significant antitumor activity against K562 by the method of MTT($IC_{50}$ were listed in Table 1.). The results inspired us to infer that the unique ether bridges from C-20 to C-7, C-14 possibly played an important role in the antitumor activity.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.426-429
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• 2004

An easy, sensitive and rapid method for the analysis of phytol, a strong ACAT (Acyl-CoA: Cholesterol Acyltransferase) inhibitory diterpenoid, was established. The pre-treatment of sample for GC analysis of phytol includes aq. MeOH extraction, partition of the extracts between EtOAc and water, and filtration of organic phase through Supelclean LC-Si SPE tube. The GC analysis of phytol for a variety of Lactuca sativa was carried out on DB-5 capillary column with flame ionization detector (FID). The consistency in phytol contents according to each variety was not shown. Especially, Jeoktoma, as RS-2 type, showed the highest phytol content.

• YAKHAK HOEJI
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• v.40 no.3
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• pp.251-261
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• 1996

Acanthopanax divaricatus Seem. is a medicinal plant growing widely through out Korea, Japan and China. The plant material of Acanthopanax spp. is used as analgesic , tonic, sedative drug as well as for the treatment of hypertension, rheumatism and diabetes. From the stem barks and root barks of A. divaricatus, diterpenoid compound was isolated and identified as pamaric acid ($C_{20}H_{30}O_2,\;mp\;164^{\circ}C$), lignan compounds were isolated and identified as d-sesamin ($C_{20}H_{18}O_6,\;mp\;123{\sim}124^{\circ}C$), eletheroside E ($C_{34}H_{46}O_{18},\;mp\;257{\sim}259^{\circ}C$), three sterol compounds were identified as ${\beta}$-sitosterol, campesterol, stigmasterol, and six fatty acid compounds were identified as stearic acid, palmitic acid, oleic acid, linolenic acid, arachidonic acid and behenic acid. And also leaves of A. divaricatus, chiisanoside were identified, one of secotriterpenoidal compound(white amorphorous powder crystal, mp $228^{\circ}C$). Anticancer activity and nephrotoxicity were tested by MTT assay. Anticancer effect of chiisanoside was much lower than that of cisplatin.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.501-507
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• 1997

Chloroplasts isolated from Stevia rebaudiana Bertoni leaves contained an enzyme activity which catalyzed hydroxylation of ent-kaurenoic acid (ent-kaur-16-en-19-oic acid; ent-KA) to steviol (ent-13-hydroxy kaur-16-en-19-oic acid), the diterpenoid carboxylic alcohol which is the aglycone of sweet stevioside-related glycosides. $[^(14)C]-methylated$ ent-KA was used to localize ent-KA hydroxylase. $[^(14)C]-methyl-KA$ was most actively was transformed into methyl-steviol in chloroplast. The enzymatic activity was found in stroma fraction but not in thylakoid membrane in Stevia rebaudiana Bertoni. However, ent-KA 13-hydroxylase activity was not detected in stroma fraction of either Spinacia oleracea and Solidago altissima. The reaction products using $[^(14)C]-methyl-KA$ were purified and identified on TLC autoradiogram. The hydroxylation of ent-KA from stromal protein to form steviol required NADPH and oxygen. FAD and riboflavin stimulated the enzyme activity 1.5-and 1.7-fold, respectively. It also turned out that the activity of this enzyme using methyl-KA as a substrate was 16.7% that of ent-KA. The purified ent-KA 13-hydroxylase did not act on t-cinnamic acid, 4-hydroxyphenyl acetic acid, choline and resorcinol, known as monooxygenase and hydroxylase substrates.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.456-461
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• 2012

The leaves of $Stevia$ $rebaudiana$ are well-known in Japan, Korea, and China as a natural sweetener. Medicinal uses of this plant originated in Paraguay and Brazil in the form of aqueous decoctions of the leaves used as a contraceptive agent and for the treatment of hyperglycemia. In the present study, the antioxidant, anti-hypertension, and anti-inflammatory activities of $S.$ $rebaudiana$ extracts are investigated for their use in food. The biologically-active compound was isolated and purified from $S.$ $rebaudiana$. The isolated compound was identified as austroinulin ($C_{20}H_{34}O_3$; molecular weight 322) by mass, IR spectrophotometry, 1D, and 2D-NMR. Austroinulin was characterized as a diterpenoid possessing a 3-methylpenta-2,4-dienyl at C-9. When subjected to an inflammatory mediator inhibitory assay from lipopolysaccharide (LPS)-activated macrophages, the austroinulin inhibited the enhanced production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS) expression (10 ${\mu}g$/mL＝67.9 and 45.1%, respectively). This was significant and dose-dependent. The results suggest that austroinulin from $S.$ $rebaudiana$ inhibited the NO and iNOS in RAW 264.7 cells.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.61 no.12
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• pp.674-680
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• 2018

Background and Objectives The representative mucin genes in the human airway are MUC5AC and MUC5B, which are regulated by several inflammatory and anti-inflammatory substances. Triptolide (TPL), udenafil, betulinic acid, changkil saponin, and glucosteroid are some of the many anti-inflammatory substances that exist. TPL is a diterpenoid compound from the thunder god vine, which is used in traditional Chinese medicine for treatment of immune inflammatory diseases, such as rheumatoid arthritis, systemic lupus erythematosus, nephritis and asthma. However, the effects of TPL on mucin expression of human airway epithelial cells have yet to be reported. Hence, this study investigated the effect of TPL on lipopolysaccharide (LPS)-induced MUC5AC and MUC5B expression in human airway epithelial cells. Subjects and Method The NCI-H292 cells and the primary cultures of human nasal epithelial cells were used to investigate the effects of TPL on LPS-induced MUC5AC and MUC5B expression using real-time polymerase chain reaction, enzyme immunoassay, and Western blot. Results TPL significantly decreased the LPS-induced MUC5AC and MUC5B mRNA expression and protein production. TPL also significantly decreased the nuclear factor-kappa B (NF-kB) phosphorylation. Conclusion These results suggest that TPL down regulates MUC5AC and MUC5B expression via inhibition of NF-kB activation in human airway epithelial cells. This study may provide important information about the biological role of triptolide on mucus-secretion in airway inflammatory diseases and the development of novel therapeutic agents for controlling such diseases.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.1-15
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• 2005

Pathogens, insects and weeds have significantly reduced agricultural productivity. Thus, to increase the productivity, synthetic agricultural chemicals have been overused. However, these synthetic compounds that are different from natural products cannot be broken down easily in natural systems, causing the destruction of soil quality and agricultural environments and the gradually difficulty in continuous agriculture. Now agriculture is faced with the various problems of minimizing the damage in agricultural environments, securing the safety of human health, while simultaneously increasing agricultural productivity. Meanwhile, plants produce secondary metabolites to protect themselves from external invaders and to secure their region for survival. Plants infected with pathogens produce antibiotics phytoalexin; monocotyledonous plants produce flavonoids and diterpenoids phytoalexins, and dicotylodoneous plant, despite of infected pathogens, produce family-specific phytoalexin such as flavonoids in Leguminosae, indole derivatives in Cruciferae, sesquitepenoids in Solanaceae, coumarins in Umbelliferae, making the plant resistant to specific pathogen. Growth inhibitor or antifeedant substances to insects are terpenoids pyrethrin, azadirachtin, limonin, cedrelanoid, toosendanin and fraxinellone/dictamnine, and terpenoid-alkaloid mixed compounds sesquiterpene pyridine and norditerpenoids, and azepine-, amide-, loline-, stemofoline-, pyrrolizidine-alkaloids and so on. Also plants produces the substances to inhibit other plant growths to secure the regions for plant itself, which is including terpenoids essential oil and sesquiterpene lactone, and additionally, benzoxazinoids, glucosinolate, quassinoid, cyanogenic glycoside, saponin, sorgolennone, juglone and lots of other different of secondary metabolites. Hence, phytoalexin, an antibiotic compound produced by plants infected with pathogens, can be employed for pathogen control. Terpenoids and alkaloids inhibiting insect growth can be utilized for insect control. Allelochemicals, a compound released from a certain plant to hinder the growth of other plants for their survival, can be also used directly as a herbicides for weed control as well. Therefore, the use of the natural secondary metabolites for pest control might be one of the alternatives for environmentally friendly agriculture. However, the natural substances are destroyed easily causing low the pest-control efficacy, and also there is the limitation to producing the substances using plant cell. In the future, effects should be made to try to find the secondary metabolites with good pest-control effect and no harmful to human health. Also the biosynthetic pathways of secondary metabolites have to be elucidated continuously, and the metabolic engineering should be applied to improve transgenics having the resistance to specific pest.

• Korean Journal of Heritage: History & Science
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• v.56 no.3
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• pp.158-171
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• 2023

Pottery filled with organic materials was excavated from the G-2 building site of Yongjangseong Fortress, Jingo, a relic of the Goryeo Dynasty. In this study, the characteristics of organic material were confirmed by a scientific analysis of organic material in pottery found at the palace in Yongjangseong, Jindo. In addition, it was intended to review the analysis method to identify the natural resin and to secure characteristic components(biomarkers) for each natural resin and use them as basic data in the future. The organic materials in the pottery were analyzed using attenuated total reflectance Fourier-transformed infrared spectroscopy(ATR-FTIR) and gas chromatography mass spectrometry(GC-MS). The infrared spectral characteristics were estimated to be natural resin, and biomarkers of organic materials were identified as sesquiterpene-based compounds(C₁₅H₂₄, MW 204) and derivatives. The lacquer(T.vemicifluum) is composed mainly of alkenes, alkanes, and catechol. Pine resin(P.densiflora), on the other hand, is primarily composed of diterpenoid(abietic acid, pimaric acid) and Whangchil(yellow lacquer) is identified to have sesquiterpenes(such as selinene, muurolene, calamenene) as its main components. So, the organic material in the pottery can be identified as Whangchil by comparing their compounds with modern resin materials from Dendropanax. morbifera that correspond with the results. Whangchil, which is exuded from the Dendropanax. morbifera, has been used as a natural coating materials since ancient times, and it has been confirmed that the characteristic components are well preserved even 700 years later. It can be assumed that the interior Whangchil was stored not for use as a coating, but rather for ritual purposes when the building was constructed, because the pottery was found near the cornerstone. Furthermore, based on simplified sample preparation using pyrolysis-gas chromatography mass spectrometry(Py-GC-MS), the thermal decomposition products were found to be similar to the characteristic components, suggesting that this method can be applied to the identification of natural resins used in historic artifacts.