• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.34-34
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• 2019

About 60% of the present drugs were developed from natural products with unique chemical diversity and biological activities. Hence, discovery of new bioactive compounds from natural products is still important for the drug development. On the other hand, breakthrough made in synthetic biology has also begun to supply us with many useful compounds through manipulation of biosynthetic gene for secondary metabolites. Theoretically, this approach can also be exploited to generate new unnatural compounds by intermixing genes from different biosynthetic pathway. Considering the potential, we are studying about bioactive compounds in natural sources, as well as the biosynthesis of natural products including engineering of the secondary metabolite enzymes to make new compounds in order to construct the methodological basis of the synthetic biology. In this symposium, engineering of secondary metabolite enzymes that are involved in the biosynthesis of plant polyketides to generate new compounds in our laboratory will be mainly introduced.

• 한국약용작물학회:학술대회논문집
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• 2011.04a
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• pp.406-407
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• 2011

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.171.1-171.1
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• 2001

• Natural Product Sciences
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• v.8 no.4
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• pp.141-143
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• 2002

Two flavone glucosides have been isolated from the leaves of Helianthus tuberosus (jerusalem artichoke). Their structures were identified as kaempferol 3-O-glucoside (1) and quercetin 7-O-glucoside (2) by spectroscopic analysis and confirmed by comparison with reported data. These flavonoids were isolated for the first time from this plant part.

• Korean Journal of Pharmacognosy
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• v.10 no.1
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• pp.1-8
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• 1979

The naturally occurring coumarins are likely to be a large and important group of plant products which are not only metabolic products of the living cells but possess varied physiological and pharmacological actions. Investigations concerning various biological activities of natural coumarins have been undertaken by many investigators in continuing effort. The authors describe on experimental results of biological activities of coumarin derivatives with particular emphasis on 10 different activities that are considered to be of importance in view of the development of new drugs from natural resources.

• Korean Journal of Pharmacognosy
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• v.17 no.2
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• pp.161-167
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• 1986

The smear method developed by Velaskar and Chitre was modified to allow the screening of plant extracts and/or fractions for platelet anti-aggregating activity. The modified smear method was also found suitable for massive screening of pure compounds. Sample fractions prepared from various plant extracts were examined for their effects against ADP, arachidonic acid (AA) or collagen induced platelet aggregations. Several solvent fractions of plant extracts including water fraction prepared from the methanol extract of Acanthopanax sp. was inhibitory against rat platelet aggregations. The activity guided treatments and fractionations of the water fraction from A. senticosus Max yielded two anti-platelet aggregatory substances, 3, 4-dihydroxybenzoic acid (I) and its artefact ethyl 3, 4-dihydroxybenzoate(II). The inhibitory activities of I and II against rat platelet aggregation were compared with that of aspirin, a known inhibitor of platelet aggregation. Discussions also included the results of the investigations on the structural activity relationships among the various dihydroxybenzoic acid derivatives against platelet aggregations induced by either one of ADP, AA or collagen.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.375.1-375.1
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• 2002

As part of a research program on the bioactive terpene constituents of Korean compositae plants. we have investigated Cacalia koraiensis (compositae). collected from Gangwon Province on August 2001. On reviewing the literatures of this species. triterpenes and pyrrolizidine alkaloids were isolated and some pharmacological activities were investigated. This species have been used for tinea and spasmolysis However. chemical constituents of this plant have not been reported. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.374.2-374.2
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• 2002

Siegesbeckia pubesence (Cempesitae). a perenial herb, is widely distributed in our country and has been used for rheumaic arthritis, hypertension, malaria. neurasthnia and snake-bite in traditional Chinese medicine. On reviewing the literatures of this plant. diterpenoids and alkaloids were isolated and some pharmacological activities were investigated. As part of our systematic study fer Korean Compositae plants, we have investigated Siegesbeckia pubesence (7kg), cellected from Mt. Odae on Aug. 2001. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.198.1-198.1
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• 2003

As part of our systematic study for Korean Compositae plants, we have studied Saussurea nutans, collected at Gangwon Province on August 2001. Phytochemical studies on various species of genus Saussurea have resulted in the isolation sesquiterpene, triterpene and flavonoid$\^$1)/. S. nutans has been used for the treatment of rheumatic arthritis and dysmenorrhea in the Chinese folk medicine$\^$2)/. However, chemical constituents of this plant have not been reported until now. The MeOH extract of the aerial parts of this source was solvent fractionated into n-hexane, methylene chloride, ethyl acetate and BuOH soluble portions. (omitted)

• Natural Product Sciences
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• v.9 no.4
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• pp.299-303
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• 2003

For the screening of inhibitors of sterol biosynthesis from natural products, a simple and rapid assay method was developed using recombinant yeast carrying human lanosterol synthase, main target of this assay method. Sterol biosynthesis inhibition activity was monitored only by the inhibition of growth of the recombinant yeast. By changing the substrate, this assay method can figure out which step is inhibited in the sterol biosynthesis by the test material. With this assay method total 102 plant samples were screened for their inhibitory activity of sterol biosynthesis. Among plant water extracts screened, 11 plant samples showed inhibitory activity on sterol biosynthesis in ergosterol (-) medium. For selection of the specific inhibitory materials, 11 plant samples were reassayed in ergosterol (+) medium. After all 5 plant samples, Abutilon avicennae Gaertn. (stem), Alnus japonica Steud. (stem), Amaranthus mangostanus L. (aerial part), Philadelphus schrenckii Pupr. (leaf) and Pimpinelia brachycarpa Nakai (aerial part), showed specific inhibitory activity.