• Proceedings of the PSK Conference
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• 2003.04a
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• pp.261.2-262
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• 2003

In the course of our researches for biologically active compound from Korean algae, purification of the methanolic extracts of two brown algae (Sagassum Sagamianum and Ishige Okamurae) collected off Jeju Island afforded an antioxidant polyphenolic compound (1). The molecular formular of 1 was established as C$\sub$24/H$\sub$16/ O$\sub$13/ on the basis of the FAB mass and $\^$13/C NMR spectrum. (omitted)

• Natural Product Sciences
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• v.21 no.3
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• pp.147-149
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• 2015

Two terpenoids, including one uniquely aromatized one (1), were isolated from CH₂Cl₂-soluble fraction of MeOH extracts of Curcuma zedoaria. They were identified to be a sesquiterpene ketolactone (1) and orobanone (2), respectively on the basis of their NMR data. The structure of compound 1 was confirmed by X-ray chrystallography and the reported NMR assignments for 1 were revised in this study. Antibiotic activities for compounds 1 and 2 were evaluated using disk diffusion assay. Compound 1 showed potent antibacterial activities against Listeria monocytogenes and Staphylococcus pseudointermedius while compound 2 was active against Bacillus cereus.

• Natural Product Sciences
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• v.22 no.3
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• pp.216-219
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• 2016

The microbial transformation of anthranilic acid (1) by the marine-mudflat-derived fungus Thielavia sp. produced an antibacterial polycyclic quinazoline alkaloid, thielaviazoline (2). The stereostructure of the metabolite was assigned based on detailed spectroscopic data analyses including comparison of the NMR ($^1H$ and $^{13}C$) data with those of reported compound (2). Compound 2 displayed in vitro antimicrobial activity against methicillin-resistant and multidrug-resistant Staphylococcus aureus (MRSA and MDRSA), with minimum inhibitory concentrations (MICs) of 6.25 and $12.5{\mu}g/mL$, respectively. Compound 2 also showed potent radical-scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) with an $IC_{50}$ of $11{\mu}M$, which was more active than the positive control, L-ascorbic acid ($IC_{50}$, $20.0{\mu}M$).

• Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.175-178
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• 2006

An acidic ent-cyclic peroxide was isolated from a sponge, Plakotis sp., and showed activity against leishmaniasis and pathogenic fungi. To improve the activity of this compound, we coupled the acidic ent-cyclic at the C1 position of ircinol A. Compound 3 exhibited significant activity against Leishmania mexican a and fungi with $IC_{50}$ values of 0.7 and $0.3-34{\mu}g/mL$, respectively. The yield of compound 3 was 98%.

• Archives of Pharmacal Research
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• v.17 no.6
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• pp.411-414
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• 1994

Phenylazocyanothioacetamide 1 reacts with malononitrile to afford the pyridinethione 4 which reacts with phenacylbromide to yield the pyridine-S-phenacyl derivative 6, 1 reacts with ethyl cyanoacetate to yield the pyridazine derivative, 8, and with phenacyl bromide to afford the N-phenacyl derivative 11, instead of the thiazole 10. Compound 11 afforded the pyrazolopyridine 13 on reaction with malononitrile while 10 was obtained on coupling of the thiazole 14 with diazotised aniline. Compound 10 reacts with malononitrile to afford the thizaolyl pyridazine 15. Compound 1 reacts with malononitrile dimer to afford the pyriodopyridazine derivative 17a. 1 reacts also with active methylene heterocycies to afford the pyrazolo and thiazolo-fused phridazines 20 and 23 respectively.

• Korean Journal of Plant Resources
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• v.20 no.3
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• pp.221-225
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• 2007

The plant Ligularia fischeri var. spiciformis (Compositae) is a candidate for available functional foods. It has been used to treat diabetes mellitus and rheumatoid arthritis. We have reported the isolation of a new eremophilanolide named 6-oxoeremophilenolide and cytotoxic intermedeol together with the isolation of hydrophilic constituents, chlorogenic acid, 3,4-di-O-caffeoylquinic acie (3), and 5-O-[1-butyl]-3,4-di-O-caffeoylquinic acid. Compound 3 was again isolated by combination of silica gel- and ODS column chromatography for the anti-nociceptive action. Compound 3 and 4 were assayed in hot plate- and writhing tests in the rat. Although the three derivatives of caffeic acid exhibited significant anti-nociceptive effects at 10 mg/kg dose (i.p.),(activity potency: 4>3). These results suggest that compound 3 is responsible for at least rheumatoid arthritis, and caffeic acid moiety is the active moiety of dicaffeoylquinic acid.

• Korean Journal of Pharmacognosy
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• v.24 no.3
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• pp.219-222
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• 1993

An antihyperglycemic compound in a model of alloxan induced diabetic rats was isolated from the root bark of Aralia elata. The compound identified to be oleanolic acid $28-O-{\beta}-_D-glucopyranoside$ was active at a dose of 100 mg/kg p.o. in the rats. It also has increased the contents of liver glycogen which were lowered by injection of alloxan in the rats.

• BMB Reports
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• v.28 no.4
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• pp.290-292
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• 1995

Existence of a binding site for choline esters with an acyl chain of various sizes was examined by comparing the inhibitory potency of the respective compound. In contrast to acetylcholine, which showed a pure competitive pattern of inhibition, choline esters with an acyl chain of a long size ($C{\geq}5$) expressed a mixed type of inhibition. Binding of choline esters containing a long chain ($C_7-C_{12}$) to the hydrophobic region in the active site is deduced from a linear relationship between the $K_{iE}$ value and the size of acyl moiety, and a good hydrophobicity relationship. In addition, the non-competitive component in the inhibition of acetylcholinesterase seems to be due to the interaction of choline esters with both the hydrophobic site and the trimethylammonium-binding site in the active center of the acetylated acetylcholinesterase.

• Korean Journal of Pharmacognosy
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• v.48 no.3
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• pp.208-212
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• 2017

In this study, analysis of active compounds that are believed to be highly relevant to antioxidant activity was carried out on the methanol extract and its solvent fractions of Corni fructus. The DPPH radical scavenging activity for the comparison of antioxidant activity was higher in order of aqueous fraction > methanol extract > ethyl acetate fraction > n-hexane fraction. It is similar to the order of total polyphenol contents in the samples. As a result of LC-MS analysis, phenolic acid compounds such as caffeic acid, gallic acid and chlorogenic acid and lognin, which is known as a representative active ingredient of Corni fructus, were identified as active compounds. And the antioxidative activity and the total polyphenol content of the extracts and solvent fractions were found to be related to the contents of the compounds. Particularly, it was confirmed that phenolic acid such as caffeic acid contributes to the antioxidative activity of the aqueous fraction of Corni fructus methanol extract.

• Journal of Life Science
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• v.11 no.3
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• pp.273-278
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• 2001

Removal of nitrogen compound from waste water is essential and often accomplished by biological process. Deni-trification bacterium. Paracoccus denitrificans(KCTC 2350) is employed to estimate the ability and the characteristics of denitrification. In the immobilized biological reactor system, the measurement of absolute amount of active strain in the reactor is comparatively difficult or impossible. In this study, strain immobilized denitrification reactor was designed with the unwoven texture wrapped peeped hole plastic tube to calculated the absolute amount of active strain by comparing the activity of the immobilized reactor adn the free cell reactor. The reactor system was continuous stirred tank reactor and the rate of substrate consumption was assumed to be Michaelis-Menten equation. As a result, we found that the amount of immobilized active strain was the half of the total active strain in the reactor and the time required to reach in the equilibrium state in the immobilized reactor system was shorter than that of the free cell reactor system.