• YAKHAK HOEJI
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• v.40 no.5
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• pp.574-581
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• 1996

The study was initiated to elucidate the protective mechanism by examining in vivo effect of some marine natural products, Styela plicata, Ecklonia stolonifera and Pachymeniopsis elliptica on acetaminophen-induced lipid peroxidation. The methanol extract of S. plicata prevented acetaminophen (800mg/kg, i.p.)-induced hepatotoxicity in rats as evidenced by the decreased formation of lipid peroxide. But the methanol extracts of E. stolonifera and P. elliptica were not affected on the formation of lipid peroxidation. The activities of cytochrome P-450, animopyrine N-demethylase and aniline hydroxylase were not changed by the treatment with S. plicata in comparison with acetaminophen-teated group. In acetaminophen-treated control rats, the glutathione S-transferase activity was decreased markably. However. in S. plicata pretreated group, the effect caused by acetaminophen was markably reduced. A-cetaminophen decreased the level of hepatic, glutathione, which was restored to same degree by S. plicata pretreatment. And activity of ${\gamma}$-glutamylcystein synthetase was not changed by S. plicata pretreatment, but the activity of glutathione reductase was increased significantly.

• Natural Product Sciences
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• v.4 no.2
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• pp.88-90
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• 1998

An acid polysaccharide (SFP), was extracted from alga Sargassum fusiforme in hot water, was purified by ion exchange chromatography on DEAE-cellulose. The PC, chemical analysis, electrophoresis and IR of SFP indicated that it was a kind of alginate with a mol. wt. of 13,000 and a molar ratio of mannuronic acid to guluronic acid 2.75. Pharmacological tests showed that SFP could prolong the survival duration of mice suffering from ascitic Sarcoma 180 with a rate of life prolongation of 63.44%.

• Natural Product Sciences
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• v.26 no.4
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• pp.303-310
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• 2020

Four new merohexapenoids named calyxaprenols A-D (1 - 4), together with the known compound haliclotriol A (5), have been isolated from the marine sponge Calyx sp. which was collected from the southwest islands of Palau. Based on comprehensive spectroscopic analyses, calyxaprenols A (1) and B (2) were determined to be pentacyclic hexaprenoids that are appended to a glycolic acid-substituted phenol moiety, whereas calyxaprenols C (3) and D (4) possess a tricyclic hexaprenoid skeleton joined to a hydroquinone ring. Identification of new merohexaprenoids from a Calyx sponge expands the known taxonomic distribution of this sparsely distributed class of marine metabolites and increases the chemical diversity described for this genus of marine sponge.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.2
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• pp.85-93
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• 2006

This study was conducted to evaluate the optimal processing conditions of smoke-dried powdered oysters and to determine their shelf-life during storage for development of a natural oyster flavoring substance. The optimal conditions for processing of smoke-dried oyster powder with freshy oyster were as follows. Raw shelled oysters were rinsed with 3% saline solution, drained, boiled for 10 minutes at $98^{\circ}C$, and then smoked for 1 hour at $50^{\circ}C$, followed by drying for 4 hours at $80^{\circ}C$ Smoke-dried oyster powder with oyster scraps were prepared as flavoring material. The smoked oyster scraps were submerged in oyster sauce far 10 minutes at room temperature and then dried with hot air for 5 hours at $50^{\circ}C$. The smoke-dried oysters and smoke-dried oyster scraps were then pulverized to 50 mesh and packed in tea bags or vacuum-packed in laminated plastic film bags (PE/PVDC/CPP, $12{\mu}m/15{\mu}m/50{\mu}m$). Compared to non smoke-dried powdered oysters, the smoking and dipping in oyster sauce enhanced the flavor and prevented lipid oxidation of the smoke-dried powdered oyster product. Shelf-life tests indicated that the vacuum-packaging method preserved the quality of smoke-dried powdered oysters stored for 150 days at room temperature.

• Natural Product Sciences
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• v.20 no.3
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• pp.202-205
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• 2014

Three compounds including 7,7-bis(3-indolyl)-p-cresol (1), cyclo-(S-Pro-R-Leu) (2) and cyclo-(S-Pro-R-Val) (3) were isolated from the strain of Bacillus megaterium LC derived from the marine sponge Haliclona oculata. All the isolated compounds showed antimicrobial activity at MIC values ranging from 0.005 to $5{\mu}g/mL$ against Gram-negative bacteria Vibrio vulnificus and V. parahaemolyticus, gram-positive bacteria Bacillus cereus and Micrococcus luteus, and the dermatophyte Trichophyton mentagrophytes. The results suggested that these compounds might have potential to be developed as agents treating dermatosis and controlling vibriosis in aquaculture.

• Natural Product Sciences
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• v.24 no.4
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• pp.247-252
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• 2018

Halophytes are expected to possess abundant secondary metabolites and various biological activities because of habitat in extreme environments. In this study, we collected 14 halophytes (Asparagus oligoclonos, Calystegia soldanella, Carex pumila, Chenopodium glaucum, Elymus mollis, Glehnia littoralis, Limonium tetragonum, Messerschmidia sibirica, Rosa rugosa, Salsola komarovii, Spergularia marina, Suaeda glauca, Suaeda maritima, and Vitex rotundifolia) native to Korea and compared their total polyphenol contents, antioxidant and anti-inflammatory activities. The total polyphenol contents of R. rugosa (27.28%) and L. tetragonum (13.17%) were significantly higher than those of the other 12 halophytes and L. tetragonum, R. rugosa, and M. sibirica showed significantly greater antioxidant activities than the other 11 halophytes, as determined by DPPH (2,2-diphenyl-1-picrylhydrazyl). A. oligoclonos, E. mollis, and C. pumila showed significantly greater anti-inflammatory activities than the other 11, as determined by NO (Nitric oxide) and $PGE_2$ (Prostaglandin $E_2$) levels. In contrast, these three extracts had normal and low total polyphenol contents among the 14 halophytes. Consequently, the total polyphenol content in the 14 studied halophytes appeared to be related to antioxidant, but not anti-inflammatory activity levels.

• Natural Product Sciences
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• v.5 no.2
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• pp.93-96
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• 1999

A new ergosteryl myristate (1) and ergosterol (2) have been isolated from the organic extract of the mycelium of unidentified marine algicolous fungus, isolate MF001. The structure of a new compound was assigned on the basis of comprehensive spectroscopic analyses and chemical synthesis.

• Natural Product Sciences
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• v.13 no.3
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• pp.251-254
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• 2007

Dioxopiperazine alkaloids, 12R,13S-dihydroxyfumitremorgin C (1), fumitremorgin C (2), and brevianamide F (3), were isolated from the marine-derived fungus Pseudallescheria, and the absolute stereostructures of compounds 1 - 3 were elucidated on the basis of chemical and physicochemical evidence. Compounds 1 - 3 showed an antibacterial activity against Staphylococcus aureus, methicillin-resistant S. aureus, and multidrug-resistant S. aureus. The MIC (minimum inhibitory concentration) values of compounds 1 - 3 were 125 ${\mu}g/mL$ for all strains.

• Natural Product Sciences
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• v.13 no.3
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• pp.247-250
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• 2007

A new sphingosine (1) was isolated from the MeOH extract of a marine sponge Haliclona (Reniera) sp. by bioactivity-guided fractionation. The 1D and 2D NMR, and MS spectroscopic analyses were used to establish the planar structure of 1. The stereochemistry of the compound was defined on the basis of modified Mosher's method, comparison of optical rotation and NMR data with those of the reported. Compound 1 was mildly cytotoxic to a panel of five human solid tumor cell lines.

• Natural Product Sciences
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• v.1 no.1
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• pp.5-9
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• 1995

The metabolites of marine mollusk Mytilus edulis were isolated and characterized, revealing the presence of the rare free fatty acids and proteinogenic amino acids together with a non-proteinogenic free amino acid, taurine. The free fatty acids in this organism were particularly interesting for the presence of both unusual n-6 acid [20:4 (n-6)] and triple bond containing acid (2,5-octadecadiynoic acid). In addition to the proteinogenic amino acids commonly found in proteins, non-proteinogenic free amino acid taurine was isolated and the structure was determined by its physicochemical properties. Recently taurine has been given much interest in the molecular level because of diverse biological activities and the medicinal properties. Furthermore, the result of the analyses of analyses of free amino acids showed that glycine, glutamic acid, serine and alanine, which were considered to be related to the taste of this organism, are predominantly present.