Biomedical subjects

Sam Sik Kang

Publications and source records attributed to Sam Sik Kang.

At least 55 records · Page 3Linked to original sources

PubMed2004

Cytoprotective effect on oxidative stress and inhibitory effect on cellular aging of Terminalia chebula fruit.

The ethanol extract from the fruit of Terminalia chebula (Combretaceae) exhibited significant inhibitory activity on oxidative stress and the age-dependent shortening of the telomeric DNA length. In the peroxidation model using t-BuOOH, the T. chebula extract showed a notable cytoprotective effect on the HEK-N/F cells with 60.5 +/- 3.8% at a concentration of 50 microg/ml. In addition, the T. chebula extract exhibited a significant cytoprotective effect against UVB-induced oxidative damage. The life-span of the HEK-N/F cells was elongated by 40% as a result of the continuous administration of 3 microg/ml of the T. chebula extract compared to that of the control. These observations were attributed to the inhibitory effect of the T. chebula extract on the age-dependent shortening of the telomere, length as shown by the Southern blots of the terminal restriction fragments (TRFs) of DNA extracted from subculture passages.

DNA↗

PubMed2004

Antiinflammatory activity of Synurus deltoides.

Synurus deltoides Aiton, Nakai, is an edible plant that has been used as a folk medicine for treating inflammatory disorders. This investigation was carried out to establish the antiinflammatory activity of this plant material using a 75% ethanol extract from the aerial part of S. deltoides. Against the acute inflammatory animal model of mouse croton oil-induced ear oedema assay, the extract did not show significant inhibition at 100-800 mg/kg by oral administration. On the other hand, the extract showed considerable inhibition against the chronic inflammatory animal model of rat adjuvant-induced arthritis (25% inhibition at 100 mg/kg/day) while prednisolone exerted 40% inhibition at 10 mg/kg/day. In addition, S. deltoides possessed strong analgesic activity (IC50 = 50 mg/kg) in the acetic acid-induced writhing test. From the extract, ursolic acid and scopoletin were successfully isolated and their contents were found to be 0.31% and 0.37% (w/w), respectively, based on the dried extract by HPLC analysis. All the results obtained indicate that this plant material may be used beneficially as an antiinflammatory agent having analgesic action.

Acetic Acid↗

PubMed2004

Prenylated flavonoids as tyrosinase inhibitors.

In order to find new tyrosinase inhibitors and the effects of prenyl residue on flavonoid molecules, eight prenylated and three synthetic vinylated flavonoids were examined on their inhibitory effect against tyrosinase activity. From the results, kuwanon C, papyriflavonol A, sanggenon D and sophoflavescenol were found to possess the considerable inhibitory activity. Especially, sanggenon D is revealed as a potent inhibitor (IC50 = 7.3 microM), compared to the reference compound, kojic acid (IC50 = 24.8 microM). However, the prenylation with isoprenyl group or the vinylation to flavonoid molecules did not enhance tyrosinase inhibitory activity.

Agaricales↗

PubMed2004

Cytotoxic coumarins from the root of Angelica dahurica.

Ten coumarins were isolated from the root of Angelica dahurica by repeated silica gel column chromatography. Their chemical structures were elucidated on the basic of physicochemical and spectroscopic data. Among them, oxypeucedanin hydrate acetonide (7) was isolated for the first time from this plant. Cytotoxicity of coumarins isolated were determined in vitro against L1210, HL-60, K562, and B16F10 tumor cell lines by MTT method. Pangelin (5) and oxypeucedanin hydrate acetonide (7) showed a potent cytotoxic activity with the IC50 values of 8.6 to 14.6 microg/mL against four kinds of tumor cell lines. Other compounds showed the moderate cytotoxic activity or no activity against the tumor cell lines.

Angelica↗

PubMed2004

Isolation of flavonoids and a cerebroside from the stem bark of Albizzia julibrissin.

From the EtOAc fraction of the MeOH extract of Albizzia julibrissin (Leguminosae), a rare 5-deoxyflavone (geraldone, 1), isookanin (2), luteolin (3), an isoflavone (daidzein, 4), five prenylated flavonoids [sophoflavescenol (5), kurarinone (6), kurarinol (7), kuraridin (8) and kuraridinol (9)], a cerebroside (soya-cerebroside I, 10), and (-)-syringaresinol-4-O-beta-D-glucopyranoside (11) were isolated and characterized on the basis of spectral data. Compounds 2, 3, and 11, showed 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity.

Albizzia↗

PubMed2004

Anti-inflammatory activity of Sedum kamtschaticum.

Sedum kamtschaticum Fischer (Crassulaceae) has been used as a folk medicine in North-East Asia for treating inflammatory disorders. The present investigation was carried out to establish in vivo anti-inflammatory activity and cyclooxygenase-2 modulating activity of this plant material. The methanol extract of Sedum kamtschaticum significantly inhibited mouse croton oil-induced ear edema (24-47% inhibition at 50-400 mg/kg) and rat paw edema (24-30% inhibition at 400-800 mg/kg) by oral administration. Prednisolone (10 mg/kg) showed 54 and 36% inhibition in the same animal models, respectively. Sedum kamtschaticum also showed significant inhibitory activity against mouse ear edema induced by multiple treatment of phorbol ester for 3 days. In addition, Sedum kamtschaticum exhibited potent analgesic activity against mouse acetic acid-induced writhing (IC50=125 mg/kg), while aspirin (200 mg/kg) showed 57% inhibition. Using lipopolysaccharide-treated RAW 264.7 cells, down-regulation of cyclooxygenase-2 expression was found to be one of the cellular action mechanisms of anti-inflammation by Sedum kamtschaticum.

Animals↗

PubMed2004

New lanostane-type triterpenoids from Ganoderma applanatum.

Four new lanostane-type triterpenes were isolated from the MeOH extract of the fruiting bodies of Ganoderma applanatum. Their structures were established as 3beta,7beta,20,23xi-tetrahydroxy-11,15-dioxolanosta-8-en-26-oic acid (1), 7beta,20,23xi-trihydroxy-3,11,15-trioxolanosta-8-en-26-oic acid (2), 7beta,23xi-dihydroxy-3,11,15-trioxolanosta-8,20E(22)-dien-26-oic acid (3), and 7beta-hydroxy-3,11,15,23-tetraoxolanosta-8,20E(22)-dien-26-oic acid methyl ester (4), respectively, by extensive spectroscopic analyses.

Canada↗

PubMed2004

Antioxidant activity of jionoside D from Clerodendron trichotomum.

The antioxidant property of jionoside D, isolated from Clerodendron trichotomum (Verbenaceae), was investigated. This compound showed scavenging activity of intracellular reactive oxygen species and of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, as well as lipid peroxidation inhibitory activity. This radical scavenging activity of jionoside D protected the cell viability of Chinese hamster lung fibroblast (V79-4) cells exposed H2O2. Furthermore, jionoside D reduced the apoptotic cells induced by H2O2, as demonstrated by the decreased number of sub G1 hypo-diploid cells and apoptotic body formation. However, it increased the activities of cellular antioxidant enzymes, superoxide dismutase and catalase. Taken together, these findings suggest that jionoside D, isolated from C. trichotomum, exhibits antioxidant properties.

Animals↗

PubMed2004

A new 2-arylbenzofuran with antioxidant activity from the black colored rice (Oryza sativa L.) bran.

From the black colored rice bran of Oryza sativa cv. Heugjinjubyeo, a new 2-arylbenzofuran, 2-(3,4-dihydroxyphenyl)-4,6-dihydroxybenzofuran-3-carboxylic acid methyl ester, oryzafuran (1), was isolated. Its structure has been elucidated on the basis of spectral data. This compound showed strong antioxidative activity in a 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay.

Antioxidants↗

PubMed2004

Phenolic glycosides from the stem bark of Albizzia julibrissin.

From the stem bark of Albizzia julibrissin DURAZZ (Leguminosae), two new phenolic glycosides (albibrissinosides A and B) were isolated. Their structures were determined by spectroscopic analysis. The albibrissinoside B was found to be a radical scavenger on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical.

Albizzia↗

PubMed2004

Phenolic glycosides from Pyrola japonica.

Five new phenolic glycosides, 2-beta-D-glucopyranosyloxy-5-hydroxyphenylacetic acid methyl ester (4), 4-hydroxy-2-[3-hydroxy-3-methylbutyl]-5-methylphenyl beta-D-glucopyranoside (5), 4-hydroxy-2-[(E)-4-hydroxy-3-methyl-2-butenyl]-5-methylphenyl beta-D-glucopyranoside (7), 4-hydroxy-2-[(2E,6Z)-8-beta-D-glucopyranosyloxy-3,7-dimethylocta-2,6-dien-1-yl]-5-methylphenyl beta-D-glucopyranoside (8), and 2,7-dimethyl-1,4-dihydronaphthalene-5,8-diol 5-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranoside (10), were isolated from the whole plants of Pyrola japonica (Pyrolaceae), together with androsin, (-)-syringaresinol glucoside, homoarbutin, pirolatin, hyperin, monotropein and chimaphilin.

Glycosides↗

PubMed2004

Triterpenoid saponins from the roots of Sophora koreensis.

From the roots of Sophora koreensis (Fabaceae), three new oleanene-type triterpene glycosides, echinosophorosides A(1) (1) and B (2), and acetyl-subproside II (5), were isolated as their methyl esters, together with the four known ones sophoraflavoside I, kudzusaponin SA(3), subproside II, and azukisaponin V. The structures of the new saponins were elucidated to be 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl(1-->2)-beta-D-glucuronopyranosyl kudzusapogenol A 22-O-alpha-L-arabinopyranoside (1), 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl-(1-->2)-beta-D-glucuronopyranosyl abrisapogenol C 22-O-alpha-L-arabinopyranoside (2), and 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl(1-->2)-beta-D-glucuronopyranosyl kudzusapogenol A 22-O-acetate (5), respectively. It is noteworthy that two arabinopyranosyl moieties in the same molecule, echinosophoroside B (2), have different conformations. The conformation of the arabinopyranosyl moiety existing in the trisaccharide moiety was determined to be (1)C(4), whereas that of the arabinopyranosyl unit at C-22 was identified as (4)C(1).

Plant Extracts↗

PubMed2003

Cerebrosides from Longan Arillus.

From the pulp of Euphoria longana (Longan Arillus), three cerebroside molecular species have been isolated. Six known cerebrosides, soyacerebrosides I and II, 1-O-beta-D-glucopyranosyl-(2S,3R,4E,8E)-2-(2'-lignoceroylamino)-4,8-octadecadiene-1,3-diol (longan cerebroside I) and its 8Z isomer (longan cerebroside II), momor-cerebroside I, and phytolacca cerebroside, were identified as major components of these cerebroside molecular species. All the cerebrosides were shown to be a mixture of geometrical isomers (8E and 8Z) of sphingosine-type or phytosphingosine-type glucocerebrosides possessing 2-hydroxy fatty acids. The structures of these cerebrosides have been determined on the basis of chemical and spectroscopic evidence.

Cerebrosides↗

PubMed2003

Alkaloidal constituents from Aconitum jaluense.

Aconitum jaluense Komar. (Ranunculaceae) is one of the Aconitum plants growing in Korean peninsula. An investigation of the alkaloidal constituents of this species led to the isolation of seven C19-norditerpenoid and a C20-diterpenoid alkaloid. Three of them have been identified as neoline, mesaconitine, and hypaconitine, which were isolated from this plant collected from Mt. Bultasan in the north part. The other five alkaloids were determined as lipomesaconitine, lipohypaconitine, 15alpha-hydroxyneoline, hokbusine A, and napelline, which have not been found in this plant. Structures of those alkaloids were determined on the basis of their spectral data. It is of interest to note that a comparison of the present work and the previous report showed some differences in the alkaloidal contents.

Aconitine↗

PubMed2003

Anti-oxidant activities of fucosterol from the marine algae Pelvetia siliquosa.

The anti-oxidant activities of fucosterol isolated from the marine algae Pelvetia siliquosa were investigated. Fucosterol exhibited a significant decrease in serum transaminase activities elevated by hepatic damage induced by CCl4-intoxication in rats. Fucosterol inhibited the sGOT and sGPT activities by 25.57 and 63.16%, respectively. Fucosterol showed the increase in the anti-oxidant enzymes such as hepatic cytosolic superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-px) activities by 33.89, 21.56 and 39.24%, respectively, in CCl4-intoxicated rats. These results suggest that fucosterol possess not only the anti-oxidant, but also the hepatoprotective activities in rats.

Administration, Oral↗

PubMed2003

Anti-tumor activities of decursinol angelate and decursin from Angelica gigas.

The in vivo anti-tumor activities of decursinol angelate (1) and decursin (2) isolated from the roots of Angelica gigas were investigated. These two compounds, when administered consecutively for 9 days at 50 and 100 mg/kg i.p. in mice, caused a significant increase in the life span and a significant decrease in the tumor weight and volume of mice inoculated with Sarcoma-180 tumor cells. These results suggest that decursinol angelate (1) and decursin (2) from A. gigas have anti-tumor activities.

Angelica↗

PubMed2003

A new (E)4-hydroxy-dodec-2-enedioic acid from the stem bark of Albizzia julibrissin.

A new unsaturated hydroxy acid was isolated from the stem bark extract of Albizzia julibrissin through repeated silica gel and Sephadex LH-20 column chromatography. The chemical structure of the new acid was determined as (E)-4-hydroxy-dodec-2-enedioic acid on the basis of several spectral data including 2D-NMR. The stereochemical feature of the double bond was determined to be E on the basis of the coupling pattern of related proton signals in the 1H-NMR and COSY experiments.

Albizzia↗

PubMed2003

Anti-inflammatory activity of Elsholtzia splendens.

Elsholtzia splendens Nakai has been used in North-East Asia as an ingredient of folk medicines for treating cough, headache and inflammation. The present investigation was carried out to establish its in vivo anti-inflammatory activity using several animal models of inflammation and pain. The 75% ethanol extract of the aerial part of E. splendens significantly inhibited mouse croton oil-induced, as well as arachidonic acid-induced, ear edema by oral administration (44.6% inhibition of croton oil-induced edema at 400 mg/kg). This plant material also showed significant inhibitory activity against the mouse ear edema induced by multiple treatment of phorbol ester for 3 days, which is an animal model of subchronic inflammation. In addition, E. splendens exhibited significant analgesic activity against mouse acetic acid-induced writhing (50% inhibition at 400 mg/kg), while indomethacin (5 mg/kg) demonstrated 95% inhibition. E. splendens (5-100 microg/mL) significantly inhibited PGE2 production by pre-induced cyclooxygenase-2 of lipopolysaccharide-treated RAW 264.7 cells, suggesting that cyclooxygenase-2 inhibition might be one of the cellular mechanisms of anti-inflammation.

Animals↗