• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.115-119
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• 2007

To discover the sources with antioxidant and tyrosinase inhibitory activities in Korean traditional medicines, 10 extract of medicinal plants were screened for their potential to scavenge stable 1,1-diphenyl-2-picryhydrazyl (DPPH) free radical, inhibit hydroxyl radical (${\cdot}OH$), total phenolic content, and inhibition of tyrosinase. The potency of DPPH radical scavenging activity was shown in the extract of Ulmus davidiana var. japonica Nakai that has a greater effect with $IC_{50}$ values of $6.49{\pm}5.43{\mu}g/mL$, than BHA ($IC_{50}=20.99{\pm}0.74{\mu}g/mL$), L-ascorbic acid $(IC_{50}=20.59{\pm}1.06{\mu}g/mL),\;and\;{\alpha}-tocopherol\;(IC_{50}=25.55{\pm}0.26{\mu}g/mL)$ as a positive control. The ${\cdot}OH$ scavenging activities were observed in the plants tested. Acanthopanax senticosus, Cirsium setiders, U. davidiana exhibited scavenging activity of more than 60% at $500{\mu}g/mL$. The scavenging activity(%) of BHA and a-tocopherol were 64.32 and 55.87% at $500{\mu}g/mL$, respectively. The total phenolic content was determined, in order to assess its effect on the extract's antioxidant activity. The total phenoic content of $33.37{\pm}0.52mg/g$ was conformed by methanolic extract of U. davidiana. The U. davidiana and Morus bombycis exhibited tyrosinase inhibitory activity with a $34.28{\pm}1.32\;and\;75.57{\pm}1.10%$, respectively. In particular, M. bombycis has stronger tyrosinase inhibitory activity than albutin with $36.48{\pm}3.56%$ as a positive control. This work showed that the inhibitory abilities of Korean medicinal plants, such as U. davidiana and M. bombycis, on DPPH free radical, inhibit hydroxyl radical (${\cdot}OH$), and inhibition of tyrosinase and total phenolic content, can be useful in the prevention and treatment of free radical-relate disease. Investigations into further isolation of inhibitory principles of U. davidiana and M. bombycis are now in progress.

• Archives of Pharmacal Research
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• v.29 no.11
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• pp.969-976
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• 2006

Novel chalcones were found as potent inhibitors of interleukin-5 (II-5). 1-(6-Benzyloxy-2-hydroxyphenyl)-3-(4-hydroxyphenyl)propenone (2a, 78.8% inhibition at $50\;{\mu}M,\;IC_{50}=25.3\;{\mu}M$) was initially identified as a potent inhibitor of IL-5. This activity is comparable to that of budesonide or sophoricoside (1a). The benzyloxy group appears to be critical for the enhancement of the IL-5 inhibitory activity. To identify the role of this hydrophobic moiety, cyclohexyloxy (2d), cyclohexylmethoxy (2c), cyclohexylethoxy (2e), cyclohexylpropoxy (2f), 2-methylpropoxy (2g), 3-methylbutoxy (2h), 4-methylpentoxy (2i), and 2-ethylbutoxy (2j) analogs were prepared and tested for their effects on IL-5 bioactivity. Compounds 2c ($IC_{50}=12.6\;{\mu}M$), 2d ($IC_{50}=12.2\;{\mu}M$), and 2i ($IC_{50}=12.3\;{\mu}M$) exhibited the most potent activity. Considering the cLog P values of 2, the alkoxy group contributes to the cell permeability of 2 for the enhancement of activity, rather than playing a role in ligand motif binding to the receptor. The optimum alkoxy group in ring A of 2 should be one that provides the cLog P of 2 in the range of 4.22 to 4.67.

• Preventive Nutrition and Food Science
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• v.20 no.1
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• pp.67-72
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• 2015

Squid is one of the most important commercial fishes in the world and is mainly utilized or consumed as sliced raw fish or as processed products. The biofunctional activities of enzymatic squid meat hydrolysate were determined to develop value-added products. Enzymatic squid hydrolysate manufactured by Alcalase effectively quenched 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, and hydrogen peroxide radical with $IC_{50}$ values of 311, 3,410, and $111.5{\mu}g/mL$, respectively. Angiotensin I-converting enzyme inhibitory activity of squid hydrolysate was strong with an $IC_{50}$ value of $145.1{\mu}g/mL$, while tyrosinase inhibitory activity with an $IC_{50}$ value of 4.72 mg/mL was moderately low. Overall, squid meat hydrolysate can be used in food or cosmetic industries as a bioactive ingredient and possibly be used in the manufacture of seasoning, bread, noodle, or cosmetics.

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1053-1056
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• 2005

Cytotoxic activitiy of seven hederagenin saponins isolated from the root of Dipsacus asper were investigated in vitro against L1210, HL-60 and SK-OV-3 tumor cell lines by the MTT method. $3-O-\alpha-L-rhamnopyranosyl-(1{\rightarrow}2)-\alpha-L -arabinopyranosyl$ hederagenin (2),\;$3-O-\beta-D­xylopyranosyl-( 1{\rightarrow}3)-\alpha-L-Rhamnopyranosyl-(1{\rightarrow}2)-\alpha-L -arabinopyranosyl$ hederagenin (6) and $3-O-\beta-D-glucopyranosyl-(1{\rightarrow}3)-\alpha-L-rhamnopyranosyl-( 1{\rightarrow}2)-\alpha-L-arabinopyranosyl$ hederagenin (7) exhibited the potent cytotoxicity against the three tumor cell lines with $IC_{50}$ values ranging from 4.7 to 8.7 ${\mu}g/mL$, with the exception of compound 7, which exhibited weak cytotoxic activity against SK-OV-3 $(IC_{50}\;22.5\;{\mu}g/mL)$. Other compounds did not exhibit any cytotoxic activity $(IC_{50}>30{\mu}g/mL)$.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1119-1124
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• 2006

The methanol extract from the aerial parts of Dictamnus albus was active in inhibiting monoamine oxidase (MAO) from the mouse brain. Activity-guided fractionation led to the isolation of four known coumarins, 7-(6'R-hydroxy-3', 7'-dimethyl-2'E, 7'-octadienyloxy) coumarin (1), auraptene (2), umbelliferone (3), and xanthotoxin (4), as active compounds along with an inactive alkaloid, skimmianine (5). Compounds 1 and 2 inhibited MAO activity in a concentration-dependent manner with $IC_{50}$ values of 0.7 and $1.7\;{\mu}M$, respectively. Compounds 1 and 2 showed a slight and potently selective inhibitory effect against MAO-B ($IC_{50}\;0.5\;and\;0.6\;{\mu}M,\;respectively$) compared to MAO-A ($IC_{50}\;1.3\;and\;34.6\;{\mu}M,\;respectively$). According to kinetic analyses derived by Lineweaver-Burk reciprocal plots, compounds 1 and 2 exhibited a competitive inhibition to MAO-B.

• Natural Product Sciences
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• v.18 no.2
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• pp.102-105
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• 2012

Marine organism extracts were prepared from 26 species of Korean indigenous marine organisms, including 25 species belonging in class Anthozoa of phylum Cnidaria and a species belonging to subphylum Urochordata of phylum Chordata, and screened their inhibitory effects against ${\mu}$-calpain. As a result, the thirteen extracts were found to be active in the criteria of $IC_{50}$ < 100 ${\mu}g/ml$. Among them, the MeOH extracts of Plexauroides praelonga and Alveopora japonica showed remarkable ${\mu}$-calpain inhibitory activity with $IC_{50}$ values of $4.62{\pm}0.22$ and $4.82{\pm}0.07{\mu}g/ml$, respectively. In addition, chemical investigation of A. japonica led to the isolation of an active compound, hexadecyl tetradecanoate, as a selective cathepsin B inhibitor ($IC_{50}=9.05{\pm}2.45{\mu}M$). This compound was isolated as constituent of A. japonica for the first time in the present study.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1349-1354
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• 2013

Twenty two new 5-fluorouracil (5-FU) derivatives, 2-butoxy-4-substituted 5-fluoropyrimidines, were synthesized and characterized by IR, $^1H$ NMR, MS, HRMS. All compounds were preliminarily evaluated by MTT assay on human liver BEL-7402 cancer cell line in vitro. Ten compounds were selected to test their cytotoxic activity against A549, HL-60 and MCF-7 cancer cell lines in vitro. These compounds were more sensitive to BEL-7402 than other cell lines, particularly, cytotoxic activity of compounds 6b, 6d-f, 6p, 6s-u were in sub-micromolar scale. The highest cytotoxic potency against A549, HL-60 and MCF-7 was shown by 2-butoxy-4-chloro-5-fluoropyrimidine (5) with $IC_{50}$ values of 0.10, 1.66 and $0.59{\mu}M$, respectively. Compounds 6d and 6e were effective against MCF-7 with $IC_{50}$ $9.73{\mu}M$ and HL-60 with $IC_{50}$ $8.83{\mu}M$, respectively.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.151-153
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• 2002

Three pseudoguaianolide type sesquiterpenes, bigelovin(1), 2,3-dihydroaromaticin (2), and ergolide (3) were isolated as inhibitory constituents against inducible nitric oxide synthase (iNOS) from the flowers of Inula britannica var. chinensis. Bigelovin (1) exhibited a highly potent inhibitory activity on lipopolysaccharide (LPS)-induced iNOS in murine macrophage RAW 264.7 cells with an $IC_{50}$ value of 0.46 mM, which is about 8 times more potent than the known selective inhibitor of iNOS, $L-N^6-(1-iminoethyl)Iysine{\;}(IC_{50}{\;}3.49{\;}{\mu}M)$. 2,3-Dihydroaromaticin (2) and ergolide (3) also exhibited potent inhibitory activities on LPS-induced iNOS with $IC_{50}$ values of 1.05 and $0.69{\;}{\mu}M$, respectively.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.456-461
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• 1996

Vascular relaxation action of crude extracts of two kinds of Coptidis rhizoma (Coptis chinensis and Coptis japonica, Ranunculaceae) was investigated and compared with that of berberine and palmatine, active alkaloid components of these plants. The results show that total extracts, berberine, and palmatine induced a concentration-dependent vasodilatation of rat thoracic aorta contracted with phenylephrine (PE). Palmatine, unlike to berberine, did not inhibit contraction induced by KCI. In calcium-free media, not only berberine but also crude extracts inhibited calcium-induced contraction. Furthermore, pretreatment of crude extracts inhibited contraction induced by PE noncompetitively. In PE-induced contraction, berberine was 2.5 times more potent than Coptis chinensis in the relaxation of rat aorta in terms of $IC_{50}$ values. Analysis of the effects of crude extracts on the Emax and $IC_{50}(PE)IC_{50}(KCI)$ ratios provides information on selectivity and indicates that extracts exhibit greater inhibition of the contrac tile response induced by PE than by KCI. We concluded that crude extracts have .alpha.-adrenoceptor blocking action and possesses inhibitory effect on calcium influx, which may be at least in part responsible for the antihypertensive action.

• Archives of Pharmacal Research
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• v.26 no.6
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• pp.463-465
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• 2003

Four protostane-type triterpenes, alisol B 23-acetate (1a), alisol C 23-acetate (2a), alisol B(3a), and alisol A 24-acetate (4a), were isolated from the rhizome of Alismatis plantago-aquatica L. var. orientale Samuelson (Alismataceae) and eleven protostane derivatives (compounds 1-11) were obtained by selective modification from alisol B 23-acetate (1a). These compounds were investigated for their anti-complement activity against the classical pathway of the complement system. Alisol B (3a) and alisol A 24-acetate (4a) exhibited anti-complement activity with $IC_{50} values of 150 and 130 \mu$ M. Among the synthetic derivatives, the tetrahydroxylated protostane triterpene (9) showed moderate inhibitory activity with $IC_{50} value of 97.1 \mu$ M. Introduction of an aldehyde group at C-23 (10; $IC_{50} value, 47.7 \mu$ M) showed the most potent inhibitory effect on the complement system in vitro.