• Archives of Pharmacal Research
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• v.28 no.12
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• pp.1324-1327
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• 2005

A methylene chloride soluble fraction of the fruits of Cudrania tricuspidata significantly inhibited the mouse brain monoamine oxidase (MAO). Three known prenylated isoflavones were isolated and identified by activity-guided fractionation. Gancaonin A (1), 4'-O-methylalpinumisoflavone (2), and alpinumisoflavone (3) inhibited MAO activity in a concentration-dependent manner with $IC_{50}$ values of 19.4, 23.9, and 25.8 $\mu$M, respectively. Of these, gancaonin A (1) showed a selective and potent inhibitory effect against MAO-B ($IC_{50}$ 0.8 $\mu$M) than MAO-A ($IC_{50}$ >800 $\mu$M). The kinetic analysis using Lineweaver-Burk plots indicated that gancaonin A (1) competitively inhibited MAO-B.

• Journal of Applied Biological Chemistry
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• v.55 no.3
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• pp.195-198
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• 2012

Four chromone derivatives (1-4) were isolated from the clove buds (Syzygium aromaticum). Of these, two chromone C-glucosides (1 and 2) showed significant PEP inhibition with $IC_{50}$ values of $1.48{\pm}0.02$ and $1.74{\pm}0.03{\mu}M$ and $K_i$ values of $0.27{\pm}0.02$ and $0.50{\pm}0.05{\mu}M$, respectively. They also exhibited strong antioxidant capacities against the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid diammonium salt radical system with $EC_{50}$ values of $4.13{\pm}0.04$ and $4.79{\pm}0.03{\mu}M$, respectively.

• Journal of Applied Biological Chemistry
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• v.56 no.3
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• pp.183-185
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• 2013

Two styrylpyranones (1 and 2) were isolated from the $CH_2Cl_2$-soluble fraction of Phellinus linteus and their structures were established by extensive Nuclear magnetic resonance (NMR) spectral data as inoscavin E and C. Both compounds showed significant prolyl endopeptidase inhibitory activity with $IC_{50}$ values of $4.26{\pm}0.14$ and $4.08{\pm}0.04{\mu}M$ and $K_i$ values of $1.50{\pm}0.02$ and $1.43{\pm}0.03{\mu}M$, respectively. They also exhibited antioxidant capacities against the ABTS radical system with $EC_{50}$ values of $6.47{\pm}0.05$ and $7.64{\pm}0.06{\mu}M$, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1200-1206
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• 2015

The major target for drug discovery, G-protein coupled receptor (GPCR) is involved in many physiological activities and related to various diseases and disorders. Among experimental techniques relating to the GPCR drug discovery process, various cell-based screening methods are influenced by cell conditions used in the overall process. Recently, the utilization of frozen cells is suggested in terms of reducing data variation and cost-effectiveness. The aim of this study is to evaluate various conditions in cell freezing such as temperature conditions and storage terms. The stable cell lines for calcium sensing receptor and urotensin receptor were established followed by storing cultured cells at $-80^{\circ}C$ up to 4 weeks. To compare with cell stored at liquid nitrogen, agonist and antagonist responses were recorded based on the luminescence detection by the calcium induced photoprotein activation. Cell signals were reduced as the storage period was increased without the changes in $EC_{50}$ and $IC_{50}$ values $EC_{50}:3.46{\pm}1.36mM$, $IC_{50}:0.49{\pm}0.15{\mu}M$). In case of cells stored in liquid nitrogen, cell responses were decreased comparing to those in live cells, however changes by storage periods and significant variations of $EC_{50}/IC_{50}$ values were not detected. The decrease of cell signals in various frozen cells may be due to the increase of cell damages. From these results, the best way for a long-term cryopreservation is the use of liquid nitrogen condition, and for the purpose of short-term storage within a month, $-80^{\circ}C$ storage condition can be possible to adopt. As a conclusion, the active implementation of frozen cells may contribute to decrease variations of experimental data during the initial cell-based screening process.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.69-69
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• 1997

In the screening of tropical medicinal plants using PAE receptor binding assay, the ether extract of Ardisia crispa showed the potent antagonistic activity. Ardisia crispa have been used to heal the scurf, earache, orchitis, fever and diarrhoea, cough and given to the mother after childbirth to ‘wash out dirty blood’ in Malaysia. By means of activity guided isolation, compound AC7-1 was isolated as the potent PAF antagonist. In this study, antiplatelet effects of compound AC7-1 were examined in vitro platelet aggregation assay using the chronolog aggregometer. Compound AC7-1 inhibited PAF-, collagen-, ADP-, thrombin-induced platelet aggregation in human, rabbit and rat platelet rich plasma. In vitro rabbit platelet aggregation, the IC$\_$50/ value of compound AC7-1 was 5 ${\times}$ 10$\^$-6/ M against PAF(5 ${\times}$ 10$\^$-7/M)-induced aggregation. The IC$\_$50/ values of AC7-1 on PAF-induced platelet aggregation increased with increase of the concentration of PAF used. This result suggested the competitive nature of the AC7-1 antagonism. In vitro rat platelet aggregation, the IC$\_$50/ values of AC7-1 on collagen-, ADP-induced platelet aggregation were 4 ${\times}$ 10$\^$-6/ M, 2 ${\times}$ 10$\^$-5/ M, respectively. Also in vitro human platelet aggregation, AC7-1 potently inhibited both the primary phase and secondary phase of thrombin-induced aggregation.

• Korean Journal of Pharmacognosy
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• v.30 no.1
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• pp.74-78
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• 1999

Nine sesquiterpene lactones, which were isolated from Hemisteptia lyrata Bunge, Chrysanthemum zawadskii Herbich var. latilobum Kitamura and Chrysanthemum boreale Makino were evaluated for the inhibition upon the nitric oxide release from the Raw cell and for the ACAT (acyl Co A: cholesterol acyltransferase) inhibitory assay. In the nitric oxide release inhibitory experiment, hemistepsin B $(IC_{50}\;=\;0.05\;{\mu}g/ml,\;0.15\;{\mu}M),$ cumambrin B, tulipinolide and costunolide exhibited strong inhibition with $IC_{50}$ values $0.05\;{\mu}g/ml\;(0.15\;{\mu}M),\;0.1\;{\mu}g/ml\;(0.38\;{\mu}M),\;0.2\;{\mu}g/ml\;(0.69\;{\mu}M)$ and $0.2\;{\mu}g/ml(0.86\;{\mu}M),$ respectively. In the ACAT inhibitory assay, angeloylcumambrin B, tigloylcumambrin B, tulipinolide and costunolide exhibited strong inhibition with $IC_{50}$ values $33\;{\mu}g/ml\;(95.4\;{\mu}M),\;22\;{\mu}g/ml\;(63.6\;{\mu}M),\;38\;{\mu}g/ml\;(151\;{\mu}M)$ and $17\;{\mu}g/ml(73.3\;{\mu}M),$ respectively, whereas other compounds did not exhibit significant activity against ACAT above $100\; {\mu}g/ml.$.

• Korean Journal of Pharmacognosy
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• v.29 no.3
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• pp.243-247
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• 1998

A diverse panel of human tumor cell lines and a mouse melanoma cell line (B16-F1) were used for the cytotoxicity test of the nine sesquiterpene lactones with ${\beta}-methylene-{\gamma}-lactone$ group isolated from Hemisteptia lyrata, Chrysanthemum zawadskii and Chrysanthemum boreale. In the cell adhesion inhibitory activity test against B16-F1 mouse melanoma cell, hemistepcin B, cumambrin B, costunolide and tulipinolide were shown significant activities with $IC_{50}$ range of 2.2, 4.1, 0.9 and $0.3\;{\mu}g/ml$, respectively. In the cytotoxicity test against human tumor cells, the most active compound was costunolide having $IC_{50}$ values of below $0.3\;{\mu}g/ml$ against all the tested cell lines except for UACC62. Cumambrin A, hendelin and costunolide exhibited more strong activity against HCT15 and UO-31 cell lines than a positive control, adriamycin. All tested compounds showed an $IC_{50}$ values of below $5.0\;{\mu}g/ml$ against all the tested cell lines.

• Natural Product Sciences
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• v.15 no.1
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• pp.27-31
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• 2009

The present study was performed to investigate the binding affinity of the ethanol extract from the leaves of Morus alba (EMA) and some EMA related plant materials (EMA-D, EMA-DM) for melanin-concentrating hormone-1 receptor (MCH-1) and also to examine the antagonistic effect of them for the recombinant MCH-1 receptor expressed in CHO cells. EMA, dichloromethane fraction (EMA-D) and EMA-DM exhibited high affinity for mammalian MCH receptor in receptor binding assays ($IC_{50}$ value: 2.3, 1.6 and $1.0{\mu}g/ml$, respectively). Other plant materials (MMA-D, MMA-DM) obtained from methanol extracts from the leaves of Morus alba (MMA) also exhibited high affinity for mammalian MCH receptor, even though the $IC_{50}$ values of them were lower than those of EMA-D and EMA-DM. In Chinese hamster ovary (CHO) cells expressing human MCH-1, EMA-DM and EMA-D significantly inhibited MCH-induced intracellular $Ca^{2+}$ increase ($IC_{50}$ values: 16.5 and $22.7{\mu}g/ml$, respectively). These results clearly indicate that the ethanol extract from the leaves of Morus alba (EMA) and some EMA related plant materials (EMA-D, EMA-DM) are novel selective MCH-1 receptor antagonist, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.498-503
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• 2015

This study was conducted to evaluate the cytotoxicity and ${\alpha}-Amylase$, ${\alpha}-Glucosidase$, pancreatic lipase inhibition in vitro by different solvent fractions from the roots of Codonopsis lanceolata. The values of $IC_{50}$ against Calu-6 cell showed a high effect in n-hexane fraction ($10.13{\mu}g/mL$) whereas DW fraction exhibited the weakest inhibition on cell viability, having an $IC_{50}$ value of over $1,000{\mu}g/mL$. The values of $IC_{50}$ against HCT-116 cell showed the highest activity in n-BuOH fraction ($102.01{\mu}g/mL$), followed by n-hexane fraction ($145.85{\mu}g/mL$), methylene chloride fraction ($332.02{\mu}g/mL$), ethyl acetate fraction ($462.93{\mu}g/mL$) and DW fracion ($>1,000{\mu}g/mL$). ${\alpha}-Amylase$ inhibitory activity in methylene chloride fraction and ethyl acetate fraction was found to have a higher inhibitory effect with 24.5% and 25.6% than the other fractions. The highest ${\alpha}-Glucosidase$ inhibitory activity was observed from the ethyl acetate fraction extract, while the extract of DW fraction showed the lowest level of inhibitory activity at given experiment concentration. The pancreatic lipase inhibitory activity of C. lanceolata was found to have a higher the effect in ethyl acetate fraction. Inhibition of lipase activity of the ethyl acetate fraction and n-hexane fraction showed a relatively high, while the extract of DW fraction showed the lowest level at given experiment concentration. These results suggested that the roots of C. lanceolata may assist in the potential biological activity on carbohydrate, lipid Inhibitory activity and anticancer activity.

• Archives of Pharmacal Research
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• v.29 no.10
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• pp.874-878
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• 2006

Methyl gallate (MG) is a medicinal herbal product that is isolated from Paeonia lactiflora that inhibits cyclooxygenase-2 (COX-2) dependent phases of prostaglandin $D_2\;(PGD_2)$ generation in bone marrow-derived mast cells (BMMC) in a concentration-dependent manner with an $IC_{50}$ values of $17.0\;{\mu}M$. This compound also found inhibited the COX-2-dependent conversion of the exogenous arachidonic acid to $PGD_2$ in a dose-dependent manner with an $IC_{50}$ values of $190\;{\mu}M$, using a COX enzyme assay kit. However, at concentrations up to $80\;{\mu}M$, MG did not inhibit COX-2 protein expression in BMMC, indicating that MG inhibits COX-2 activity directly. Furthermore, MG consistently inhibited the production of leukotriene $C_4\;(LTC_4)$ in a dose dependent manner, with an $IC_{50}$ value of $5.3\;{\mu}M$. These results demonstrate that MG has a dual cyclooxygenase-2/5-lipoxygenase inhibitory activity, which might provide the basis for novel anti-inflammatory drugs.