• YAKHAK HOEJI
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• v.49 no.1
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• pp.60-67
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• 2005

Nonclassical aminobenz[cd]indole antifolates 4, 5 and 6, in which the glutamic acid moiety of the classical antifolates is substituted by 2-phenylglycinamide or 3-aminobenzamide, were synthesized and their in vitro antitumor activity was evaluated. The purpose of this substitution is that the lipophilicity is enhanced due to the aromatic ring of the target compounds for the passive transport through lipid membrane of cells while the hydrogen bonding of the amide is retained in the active site of the enzyme, thymidylate synthase, where the glutamate is originally present. The target compounds were highly cytotoxic against tumor cell lines of murine and human origin with micromolar to nanomolar $IC_{50}$ values. Most effective was compound 4 ($N^6-methyl-N^6$-[4-[(${\alpha}$(S)-aminocarbonylbenzyl) aminocarbonyl]benzyl]-2,6-diaminobenz[cd]indole)with $IC_{50}$ of 2 nM against SW480, human colon adenocarcinoma cell line, which is 650-fold more potent than the reference compound 3.

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.497-502
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• 2006

A new natural C-benzylated chalcone, $2',4'-dihydroxy-3'-(2-hydroxybenzyl)-6{\c}-methoxychalcone$ (2), along with two other flavonoids, tiliroside and kaempferol 3-O-rutinoside, and an oxoaporphine alkaloid, lanuginosine were isolated from the aerial parts of Ellipeiopsis cherrevensis (Annonaceae). Two known polyoxygenated cyclohexene derivatives, ferrudiol and zeylenol, and a new analog, ellipeiopsol D, were also isolated. The chalcone 2 exhibited cytotoxic activity against human small-cell lung-cancer (NCl-H187), epidermoid carcinoma (KB) and breast cancer (BC) cell lines with $IC_{50}$ values of 1.40, 5.31 and $13.92\;{\mu}g/mL$, respectively. This compound also showed antimalarial activity against Plasmodium falciparum with an $IC_{50}$ value of $7.1\;{\mu}g/mL$ as well as antimicrobacterial activity against Mycobacterium tuberculosis with a MIC of 25 mg/mL.

• Journal of Life Science
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• v.10 no.2
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• pp.140-149
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• 2000

In order to utilize marine processing waste which would normally be discarded, cod liver protein was hydrolysed by ${\alpha}$-chymotrysin, and the hydrolysate was investigated for the new angiotensin I converting enzyme (ACE) inhibitor. Thy hydrolysate was separated into three major types, with molecular weight cut-off (MWCO) values less than 10 kDa, 5 kDa and 1 kDa of ultrafiltration membranes, respectively. ACE inhibitory peptides were isolated from the fractions passed through MWCO 1 kDa membrane, and purified by using ion-exchange chromatography on a SP-Sephadex C-25 column, gel filtration on a Sephadex G-15 column, and HPLC on an ODS column. The purity was identified with capillary electrophoresis. The amino acid sequences of two peptides were Met-Ile-Pro-Pro-Tyr-Tyr (IC50=10.9 ${\mu}$M) and Gly-Leu-Arg-Asn-Gly-Ile (IC50=35.0 ${\mu}$M)

• Natural Product Sciences
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• v.8 no.4
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• pp.162-164
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• 2002

The methanol extracts of 42 Korean indigenous plants were evaluated for the DNA strand-scission activity. As a result, the 17 extracts were found to be active in the criteria of $IC_{50}$}<$25\;{\mu}g/ml$. Among others, the MeOH extracts of Caesalpinia sappan and Mucuna birdwoodiana showed the most potent DNA strand-scission activity with $IC_{50}$ values of 5.9 and $4.9\;{\mu}g/ml$, respectively. Therefore, the partition and fractionation for C. sappan were performed and tested in the DNA strand-scission assay system for further bioassay-guided fractionation.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.446-448
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• 2002

The inhibitory activity of tanshinones from Salvia miltiorrhiza was tested on rat liver diacylglycerol acyltransferase (DGAT). Cryptotanshinone (1) and 15,16-dihydrotanshinone I (3) exhibited potent DGAT inhibitory activities dose-dependently with $IC_{50}$ values of $10.5 {\;}{\mu\textrm{g}}/ml{\;}and{\;}11.1{\;}{\mu\textrm{g}}/ml$. However, tanshinone IIA (2) and tanshinone I (4) showed very weak inhibition ($IC_{50}{\;}value:{\;}>{\;}250{\;}{\mu\textrm{g}}/ml$). A dihydrofuran moiety was seemed to be responsible for the stronger inhibitory activity

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.151.3-152
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• 2003

Aromatic diamine JSH-21 showed an IC50 value of 9.2 uM with 74.5% inhibition at 30 uM, 53.5% at 10 uM and 24.5% at 3 uM on LPS-induced NO production in murine macrophages Raw 264.7. To examine whether inhibitory effect on NO production by JSH-21 was attributed to influence on iNOS expression, iNOS transcript and protein were analyzed by sequantitative RT-PCR and immunoblot analysis. Consistent with previous result on NO production, treatment of the Raw 264.7 cells with JSH-21 decreased the LPS-induced expression of iNOS transcript and protein in a dose-dependent manner with IC50 values of about 10 uM. (omitted)

• Natural Product Sciences
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• v.11 no.3
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• pp.119-122
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• 2005

In the course of searching for hepatoprotective agents from natural products, four compounds were isolated from the MeOH extract of Sanguisorbae Radix, as guided by their DPPH free radical scavenging activity. The structures were determined as 4,5-dimethoxy-3-hydroxybenzoic acid methyl ester (1), (+)-gallocatechin (2), methyl $6-O-galloyl-{\beta}-D-glucopyranoside$ (3), and pomolic acid $3-O-[{\alpha}-L-arabinopyranoside]-28-O-[{\beta}-D-glucopyranosyl]$ ester (ziyu-glycoside I) (4). Compounds 2 and 3 showed significant DPPH free radical scavenging effects, exhibiting $IC_{50}$ values of 11.4 and $13.0\;{\mu}M$, respectively. L-Ascorbic acid was used as a positive control and exhibited the $IC_{50}$ value of $50.3\;{\mu}M$. In evaluation of the hepatoprotective activity of the isolated compounds on drug-induced cytotoxicity, compound 2 showed the significant hepatoprotective effect with the $EC_{50}$ value of $91.84\;{\pm}\;11.0\;{\mu}M$ on tacrine-induced cytotoxicity in Hep G2 cells, while silybin, a positive control, exhibited $EC_{50}$ value of $122.4\;{\pm}\;12.5\;{\mu}M$.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.47-50
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• 2011

To develop a new natural whitening agent, we investigated the tyrosinase inhibitory effects of Persicaria tinctoria Flower extracts (PTFE). PTFE showed inhibitory activity on mushroom tyrosinase with the $IC_{50}$ values of $70.8{\pm}2.2{\mu}g/mL$. We purified two active compounds from PTFE by LH-20 column chromatography and prep-high performance liquid chromatography (HPLC) and identified as quercetin-3-O-rhamnoside (Q3R) and myricetin-3-O-rhamnoside (M3R) by $^1H$nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LC-MS) analysis. Q3R and M3R showed tyrosinase inhibitory activities with the $IC_{50}$ values of $47.0{\pm}0.1{\mu}g/mL$ and $150.5{\pm}1.6{\mu}g/mL$, respectively. These results suggest that PTFE and its active compounds reduced melanin formation by the inhibition of tyrosinase activity. Thus, P. tinctoria flower extracts may be a candidate for cosmetic use.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.301-308
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• 2019

The antioxidant properties of Eriobotrya japonica leaf extract were investigated using DPPH and ABTS radical scavenging assay. The 80% ethanol extract of leaves ($IC_{50}$ values for DPPH and ABTS were 13.9 and $10.9{\mu}g/mL$, respectively) and young leaves ($IC_{50}$ values for DPPH and ABTS were 20.7 and $17.3{\mu}g/mL$, respectively) showed high radical scavenging activity. Additionally, the quantitative method for estimation of ellagic acid and chlorogenic acid from E. japonica leaves was optimized by HPLC/DAD. This method showed high linearity of the calibration curve with a coefficient of correlation ($R^2$) equal to 0.999. The LOD values for ellagic acid and chlorogenic acid were 2.35 and $0.73{\mu}g/mL$, respectively, whereas LOQ values were 7.13 and $2.22{\mu}g/mL$, respectively. Recovery of the two compounds was 99.7-108.0% with RSD values less than 5.31%. These results suggest that 80% ethanol extract of E. japonica leaves could serve as a potential source of natural antioxidant for us in various industrial applications.

• Food Science and Preservation
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• v.17 no.2
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• pp.290-296
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• 2010

To develop anti-acidosis and anti-diabetes agentsfrom natural products, the inhibitory activities of Brazilian plant extracts against microbial $\alpha$-amylase and $\alpha$-glucosidase were evaluated. Among 100 different ethanol extracts tested, those of Acacia jurema Mart., Anacardium humile A. St.-Hil., Cedrela odorata L., and Guazuma ulmifolia Lam showed good inhibitoryactivities toward both enzymes. In addition, an extract of Plumeria drastica Mart. showed specific inhibition of $\alpha$-amylase, whereas that of Eugenia uniflora L. demonstrated strong inhibition of the enzyme. IC50 values of $\alpha$-amylase inhibition suggested that the extract of A. humile A. St.-Hil., which has been used as an anti-diabetes medicine in Brazil, had potent inhibitory activity. The IC50 for the A. humile A. St.-Hil. extract ($91.2{\mu}g/mL$) was similar to that of acarbose ($50.5{\mu}g/mL$). This activity of A. humile A. St.-Hil. was not reduced by heat or acid treatment. Moreover, treatment with HCl (0.01 M) for 1 h increased the inhibitory activity from 57.5% to 81.2%. Also, the extract did not cause hemolysis of human red blood cells at levels up to 1 mg/mL. The results indicate that the extract of A. humile A. St.-Hil. is potentially useful as an anti-acidosis and anti-diabetes agent.