Biomedical subjects

Byung-Sun Min

Publications and source records attributed to Byung-Sun Min.

At least 19 recordsLinked to original sources

PubMed2007

Styraxoside A isolated from the stem bark of Styrax japonica inhibits lipopolysaccharide-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 in RAW 264.7 cells by suppressing nuclear factor-kappa B activation.

In the present study, the effects of terpenes (styraxosides A and B) and lignans (egonol, masutakeside I, and styraxlignolide A) isolated from the stem bark of Styrax japonica Sieb. et Zucc. (styracaceae) were evaluated on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by the RAW 264.7 macrophage cell line. Of the tested compounds, styraxoside A was found to most potently inhibit the productions of NO and PGE2, and also significantly reduced the release of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta). Consistent with these observations, the protein expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and the mRNA expression levels of iNOS, COX-2, TNF-alpha and IL-1beta were found to be inhibited by styraxoside A in a concentration-dependent manner. Furthermore, styraxoside A inhibited the LPS-induced DNA binding activity of nuclear factor-kappaB (NF-kappaB). Taken together, our data indicate that styraxoside A inhibits LPS-induced iNOS, COX-2, TNF-alpha, and IL-1beta expressions through the down-regulation of NF-kappaB-DNA binding activity.

Animals↗

PubMed2006

Two novel furan derivatives from Phellinus linteus with anti-complement activity.

Two novel stereoisomers of furan derivatives, phellinusfurans A (1) and B (2), were isolated from the fruiting body of Phellinus linteus. Their structures were elucidated by spectroscopic analysis. Compounds 1 and 2 exhibited significant anti-complement activity with IC50 values of 33.6 and 33.7 microM, respectively, in inhibiting the hemolytic activity of human serum against erythrocytes.

Basidiomycota↗

PubMed2006

Isolation of flavonoids, a biscoumarin and an amide from the flower buds of Daphne genkwa and the evaluation of their anti-complement activity.

As part of an ongoing study aimed at identifying the anti-complement active compound from the flower buds of Daphne genkwa, ten flavonoids, one biscoumarin and one amide were isolated. Their structures were identified from spectroscopic and physicochemical data as genkwanin 5-O-beta-d-primveroside (1), apigenin 7-O-beta-d-glucuronide (2), genkwanin 5-O-beta-d-glucopyranoside (3), apigenin 5-O-beta-d-glucopyranoside (4), genkwanin (5), apigenin (6), luteolin 7-methyl ether (7), luteolin (8), daphnoretin (9), velutin (10), 7-methoxyacacetin (11) and aurantiamide acetate (12). Among them, compounds 9, 10 and 12 were isolated from this plant for the first time. The anti-complement activity of these compounds was tested against the classical pathway of the complement system. Among the compounds, daphnoretin (9) exhibited significant anti-complement activity with an IC(50) value of 11.4 microm, whereas the other compounds were not active in the assay.

Amides↗

PubMed2006

Anticomplement activity of cycloartane glycosides from the rhizome of Cimicifuga foetida.

A tetranor-cycloartane glycoside and two 9,19-cycloartane glycosides were isolated from the EtOAc-soluble fraction of the rhizome of Cimicifuga foetida. The structures of the compounds were determined to be cimilactone A (1), 25-O-acetylcimigenol 3-O-beta-d-xylopyranoside (2) and cimigenol 3-O-alpha-l-arabinopyranoside (3), respectively, using spectroscopic analysis. The three compounds were examined for their anticomplement activity against the classical pathway of the complement system. Compound 1 showed significant anticomplement activity with an IC(50) value of 28.6 microm, whereas compounds 2 and 3 were inactive.

Animals↗

PubMed2006

Anti-inflammatory activity of flavonoids from Populus davidiana.

An in vitro bioassay-guide revealed that the methanol (MeOH) extract of the stem bark of Populus davidiana showed considerable inhibitory activity against cyclooxygenase (COX-1, COX-2). Continuous phytochemical study of the MeOH extract of this plant led to the isolation of ten flavonoids; sakuranetin (1), rhamnocitrin (2), 7-O-methylaromadendrin (3), naringenin (4), eriodictyol (5), aromadendrin (6), kaempferol (7), neosakuranin (8), sakuranin (9) and sakurenetin-5,4'-di-beta-D-glucopyranoside (10). Their structures were identified on the basis of their physicochemical and spectroscopic analyses. The isolated compounds, 1-10, were tested for their inhibitory activities against COX-1 and COX-2. Compound 7 was found to have potent inhibitory effect on COX-1 and a moderate effect on COX-2, meanwhile, compounds 1-6 showed moderate inhibition against COX-1 only. Moreover, compounds 5-8 exhibited suppressive effects on xanthine oxidase (XO). These results may explain, in part, the traditional uses of P. davidiana in ethnomedicine.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2006

Phenolic glycosides with antioxidant activity from the stem bark of Populus davidiana.

Phytochemical study on the EtOAc-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of 10 phenolic glycosides (1-10), which were identified on the basis of physicochemical and spectroscopic analyses. Among these, three new compounds, populosides A-C (1-3), were determined to be 2-coumaroylmethyl-4-hydroxyphenyl-beta-D-glucopyranoside, 2-coumaroylmethylphenyl-beta-D-glucopyranoside, and 2-feruoylmethylphenyl-beta-D-glucopyranoside, respectively. Compounds 1-10 were tested for their radical scavenging activity against an azo radical, ABTS*+. Of these, populosides A-C (1-3), populoside (4), grandidentatin (8), salireposide (9), and coumaroyl-beta-D-glucoside (10) exhibited antioxidant activity in this assay.

Antioxidants↗

PubMed2006

Anti-complementary activity of ursane-type triterpenoids from Weigela subsessilis.

A new ursane-type triterpenoid, weigelic acid (1), and seven known compounds, ursolic acid (2), ilekudinol A (3), corosolic acid (4), ilekudinol B (5), esculentic acid (6), pomolic acid (7), and asiatic acid (8) were isolated from the leaf and stem of Weigela subsessilis. The structure of the new triterpenoid was established as 1beta,2alpha,3alpha,23-tetrahydroxyurs-12-en-28-oic acid on the basis of spectroscopic analyses. In addition, the isolated compounds were evaluated for their anti-complement activity against the classical pathway of the complement system. Of these, compounds 1-2 and 4-8 exhibited anti-complement activity with IC50 values of 152, 90, 130, 51, 56, 4, and 163 microM, respectively, whereas 3 was inactive. This shows that a carboxylic group of ursane-type triterpenoids seems to play an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

Animals↗

PubMed2005

Two new pregnanone derivatives with strong cytotoxic activity from Pachysandra axillaris.

Two new, bioactive, pregnane-based natural products, pachysanonin (= 3beta,11alpha,12beta)-12-acetoxy-3-(dimethylamino)-11-[(3,4-dimethylpent-3-enoyl)oxy]pregnan-20-one; 1) and pachysanone (= (11alpha,12beta)-12-acetoxy-11-[(3,4-dimethylpent-3-enoyl)oxy]pregnan-3,20-dion; 2) have been isolated from Pachysandra axillaris. Their structures were determined by spectroscopic methods, and, in the case of 2, by single-crystal X-ray crystallography (Figure). Compound 2 showed significant antitumor activity against Lewis lung carcinoma (LCC) tumor cells, with an IC50 value of 0.020+/-0.006 microg/ml, which is equal or even lower than those of the well-known natural antitumor agents harringtonine (0.02), homoharringtonine (0.15), and adriamycin (0.06 microg/ml; positive control).

Antineoplastic Agents, Phytogenic↗

PubMed2005

Flavonoids from the leaves of Litsea japonica and their anti-complement activity.

Four flavonoids, epicatechin (1), afzelin (2), quercitrin (3), and tiliroside (4), were isolated from the leaves of Litsea japonica (Thunb.) Jussieu (Lauraceae). The structures of compounds were identified by comparing their chemical and spectral data with those previously reported. The flavonoids (1-4) were tested for their anti-complement activity against classical pathway of complement system. Compounds 2-4 showed inhibitory activity against complement system with IC50 values of 258, 440, and 101 microm, respectively, whereas 1 was inactive. For the evaluation of the structure-activity relationship of 5,7-dihydroxyflavones, myricitrin (5) from Juglans mandshurica also tested for it's anti-complement activity and is inactive in this assay system. Furthermore, compounds 2, 3, and 5 were hydrolyzed with naringinase to give kaempferol (2a), quercetin (3a), and myricetin (5a), and these were also tested for their activity. Of the three aglycones, 2a exhibited anti-complement activity with an IC50 value of 730 microM, while 3a and 5a were inactive. The inhibitory potencies of 2, 2a, 3, 3a, 5, and 5a against complement activity increased in inverse proportion to number of free hydroxyls on B-ring of 5,7-dihydroxyflavone. Of the compounds tested, 4 showed the most potent inhibitory activity against the complement system.

Complement Inactivator Proteins↗

PubMed2005

Neuroprotective and free radical scavenging activities of phenolic compounds from Hovenia dulcis.

The EtOAc-soluble fraction from a methanolic extract of Hovenia dulcis Thunb. exhibited neuroprotective activity against glutamate-induced neurotoxicity in mouse hippocampal HT22 cells. The neuroprotective activity-guided isolation resulted in 8 phenolic compounds (1-8), such as vanillic acid (1), ferulic acid (2), 3,5-dihydroxystilbene (3), (+)-aromadendrin (4), methyl vanillate (5), (-)-catechin (6), 2,3,4-trihydrobenzoic acid (7), and (+)-afzelechin (8). Among these, compounds 6 and 8 had a neuroprotective effect on the glutamate-induced neurotoxicity in HT22 cells. Furthermore, compound 6 had a DPPH free radical scavenging effect with an IC50 value of 57.7 microM, and a superoxide anion radical scavenging effect with an IC50 value of 8.0 microM. Both compounds 6 and 8 had ABTS cation radical scavenging effects with IC50 values of 7.8 microM and 23.7 microM, respectively. These results suggest that compounds 6 and 8 could be neuroprotectants owing to their free radical scavenging activities.

Animals↗

PubMed2005

A new furofuran lignan with antioxidant and antiseizure activities from the leaves of Petasites japonicus.

A new furofuran lignan (1) was isolated from the n-butanol fraction of the methanolic extract of the leaves of Petasites japonicus (Sieb. et Zucc.) Maxim. (Compositae). The structure of compound 1 was determined to be 2alpha-(4'-hydroxy-3'-methoxyphenyl)-6alpha-(4"-hydroxy-3"-methoxyphenyl)-8alpha-hydroxy-3,7-dioxabicyclo[3.3.0octane 4'-O-(beta-D-glucopyranoside) by spectroscopic methods including 2D-NMR. In further studies, it was found that the compound 1 expressed an antioxidant activity in DPPH radical scavenging assay, and moreover, ameliorated the seizure in kainic acid-treated mice.

Animals↗

PubMed2004

Isolation and anticomplement activity of compounds from Dendropanax morbifera.

Dendropanax morbifera Leveille (Araliaceae) is used in Korea for a variety of disease, such as migraine headache and dysmenorrhea. A new polyacetylene (1) and six known compounds (2-7) were isolated from the leaves of this plant by conventional chromatographic techniques. The structure of the new polyacetylene (1) was determined as (9Z,16S)-16-hydroxy-9,17-octadecadiene-12,14-diynoic acid by spectroscopic means including 2D NMR, which comprised the determination of a chiral by modified Mosher's ester method. Compounds 1-7 were investigated in vitro for their anticomplement activity against the classical pathway of the complement system. Of these, compound 1 showed significant anticomplement activity with 50% inhibitory concentration (IC50) value of 56.98 microM, whereas compounds 2-7 were inactive.

Araliaceae↗

PubMed2004

New furofuran and butyrolactone lignans with antioxidant activity from the stem bark of Styrax japonica.

A new furofuran lignan, styraxlignolide B (1), and four new dibenzyl-gamma-butyrolactone lignans, styraxlignolides C-F (2-5), were isolated from the EtOAc-soluble fraction of stem bark of Styrax japonica. Known compounds, taraxerol (6), syringin (7), and (-)-pinoresinol glucoside (8), were also obtained. The structures of styraxligonolides B-F were determined as 2alpha-(4'-hydroxy-3'-methoxyphenyl)-6alpha-(3' ',4' '-methylenedioxyphenyl)-8-oxo-3,7-dioxabicyclo[3.3.0]octane 4'-O-(beta-D-glucopyranoside) (1), (2S,3S)-2alpha-(3' '-hydroxy-4' '-methoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4'-O-(beta-D-glucopyranoside) (2), (2S,3S)-2alpha-(4' '-hydroxy-3' '-methoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4'-O-(beta-D-glucopyranoside) (3), (2S,3S)-2alpha-(4' '-hydroxy-3' '-methoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4' '-O-(beta-D-glucopyranoside) (4), and (2S,3S)-2alpha-(3' ',4' '-dimethoxybenzyl)-3beta-(4'-hydroxy-3'-methoxybenzyl)-gamma-butyrolactone 4'-O-(beta-D-glucopyranoside) (5) by spectroscopic means including 2D NMR. Compounds 1-8 were tested in vitro for antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Styraxlignolide C (2), styraxlignolide D (3), styraxlignolide E (4), and (-)-pinoresinol glucoside (8) exhibited weak radical-scavenging activity in the DPPH assay, with IC50 values of 380, 278, 194, and 260 microM, respectively.

4-Butyrolactone↗

PubMed2004

Furo-1,2-naphthoquinones from Crataegus pinnatifida with ICAM-1 expression inhibition activity.

Two new furo-1,2-naphthoquinones, crataequinones A (1) and B (2), were isolated from the fruits of Crataegus pinnatifida. The structures of two new compounds were determined as 11,12-dimethoxy-3,4-furo-1,2-naphthoquinone (1) and 11,12-dimethoxy-5-hydroxy-3,4-furo-1,2-naphthoquinone (2) by spectroscopic analysis. The two compounds 1 and 2 showed significant inhibitory activity with IC50 values of 33 and 90 microM, respectively, against the expression of intercellular adhesion molecule-1 (ICAM-1).

Animals↗

PubMed2004

Anti-complement activity of norlignans and terpenes from the stem bark of Styrax japonica.

A new norlignan, styraxlignolide A (1), and two new terpenes, styraxosides A (2) and B (3), were isolated from the MeOH-soluble fraction of Styrax japonica Sieb. et Zucc. (Styracaceae) stem bark, together with two known compounds, egonol (4) and masutakeside I (5). The new compounds were determined as 5-(3''-hydroxypropyl)-7-methoxy-2-(3',4'-dimethoxyphenyl)-benzofuran 3''- O-[beta-D-xylopyranoside-(1-->6)-beta- D-glucopyranoside] (1), 3beta,7beta-dihydroxy-4alpha,4beta,8beta,10beta,14alpha-pentamethyl-5alpha-gon-16-en-2-one 3-O-[beta-D-glucopyranoside-(1-->2)-beta-D-glucopyranoside] (2), and 3beta,17beta-dihydroxy-28-norolean-12-en-16-one 3-O-[alpha-L-rhamopyranoside-(1-->2)-beta-D-glucuronopyranoside] (3) by spectroscopic means including 2D-NMR. The five compounds were tested in vitro for anti-complement activity against the complement system. Compounds 1, 3, 4, and 5 displayed inhibitory activity in the anti-complement assay, with IC50 values of 123, 65, 33, and 166 microM, respectively. Compound 1a and camellenodiol (3a), obtained from acid hydrolysis of 1 and 3, respectively, did not affect the hemolytic activity of human serum against sensitized erythrocytes. This shows that a sugar seems to play a role of enhancing significantly anti-complement activity.

Complement System Proteins↗

PubMed2004

Increase of caspase-3 activity by lignans from Machilus thunbergii in HL-60 cells.

Nine lignans and two butanolides were isolated from the stem bark of Machilus thunbergii and their structures were identified as machilin A (1), licarin B (2), zuonin B (3), macelignan (4), secoisolancifolide (5), isolancifolide (6), oleiferin C (7), meso-dihydroguaiaretic acid (8), licarin A (9), machilin F (10), and nectandrin B (11) by spectroscopic means. These compounds were assessed for their abilities to activate a caspase-3 activity in human promyeloid leukemic HL-60 cells. The intracellular caspase-3 activity of macelignan (4), oleiferin C (7), meso-dihydroguaiaretic acid (8), and licarin A (9) increased approximately 3.04, 6.16, 2.10, and 3.10-fold at 100 microM over that of untreated control. In addition, compounds 4, 7, 8, and 9 induced internucleosomal DNA fragmentation in HL-60 cells.

4-Butyrolactone↗

PubMed2004

Anti-complementary activity of triterpenoides from fruits of Zizyphus jujuba.

In order to determine on the anti-complement activity of triterpenes, following eleven triterpenoides were isolated from the fruits of the Zizyphus jujuba MILL: ceanothane-type triterpenes: colubrinic acid (1), zizyberenalic acid (11); lupane-type triterpenes: alphitolic acid (2), 3-O-cis-p-coumaroyl alphitolic acid (3), 3-O-trans-p-coumaroyl alphitolic acid (4), betulinic acid (7), betulonic acid (9); and oleanane-type triterpenes: 3-O-cis-p-coumaroyl maslinic acid (5), 3-O-trans-p-coumaroyl maslinic acid (6), oleanolic acid (8), oleanonic acid (10). These compounds were examined for their anti-complement activity against the classical pathway of the complement system. Among them, compounds 5, 6, and 8 exhibited significant anti-complement activity with IC(50) values of 101.4, 143.9, and 163.4 microM, respectively, whereas the ceanothane-type and the lupane-type triterpenes were inactive. This suggests that the oleanane-structure plays an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

Chromatography, High Pressure Liquid↗

PubMed2004

Quantitative determination of bitter principles in specimens of Ganoderma lucidum using high-performance liquid chromatography and its application to the evaluation of ganoderma products.

For quantitative determination of 19 triterpene constituents, including six ganoderma alcohols (1-6) and 13 ganoderma acids (7-19), in the products of Ganoderma lucidum, an analytical system was developed using high-performance liquid chromatography with an ODS column. The mobile phase was a linear gradient of 1% AcOH/H(2)O-CH(3)CN and 2% AcOH/H(2)O-CH(3)CN, and the elution profile was monitored at 243 and 250 nm for ganoderma alcohols and acids, respectively. The relative standard deviations of this method were less than 2.35% and 2.18% (n=5) for intraday and interday assays, and the recoveries were 90.9-100.8% and 93.4-103.9% for constituents of alcohol and acid groups, respectively. This system was applied to a quantitative determination of the constituents in 10 different products of G. lucidum: six usual umbrella forms of the fruiting bodies, three antlered forms of the fruiting bodies and spores, and eight specimens from the same G. lucidum strain, which was parasitized on logs from different plants or different fungus beds. The analytical results indicated that the quantity and composition of these triterpenes differed appreciably among various specimens, but the relative ratio of the alcohols and acids was not significantly different when the same strain of G. lucidum was used.

Chromatography, High Pressure Liquid↗