• Natural Product Sciences
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• v.15 no.3
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• pp.173-179
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• 2009

To determine the cytotoxic activity of natural compounds, chromatographic separation of the hexanesoluble fraction from the fruiting body of Ganoderma lucidum led to the isolation of four steroids and one triterpenoid. They were identified as ergosterol peroxide (1), stella sterol (2), ergosterol (3), 9(11)-dehydroergostrol peroxide (4), and ganodermanontriol (5) based on spectroscopic evidence and physicochemical properties. These compounds were examined for their cytotoxic activity against HL-60, MCF-7, and LLC cancer cell lines. Ganodermanontriol (5) showed cytotoxic activity with IC$_{50}$ values of 24.8 and 22.9 $\mu$g/mL against HL-60 and MCF-7 cancer cell lines, respectively, whereas compounds 1 - 4 were inactive.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2222-2226
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• 2011

Amylase is a digestive enzyme that catalyses the starch into sugar. It has been reported that the green tea flavonoid (or polyphenols) (-)-epigallocatechin 3-gallate (EGCG) inhibits human salivary ${\alpha}$-amylase (HSA) and induced anti-nutritional effects. In this study, we performed docking study for seven EGCG-like flavonoids and HSA to understand the interaction mechanism of HSA and EGCG and suggest new possible flavonoid inhibitors of HSA. As a result, EGCG and (-)-epicatechin gallate (ECG) bind to HSA with complex hydrogen bonding interactions. These hydrogen bonding interactions are important for inhibitory activity of EGCG against HSA. We suggested that ECG can be a potent inhibitor of HSA. This study will be helpful to understand the mechanism of inhibition of HSA by EGCG and give insights to develop therapeutic strategies against diabetes.

• International journal of advanced smart convergence
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• v.7 no.3
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• pp.101-109
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• 2018

In this paper, we propose an adaptive filtering scheme of connection requests for the defense of malicious energy consumption attacks against wireless computing devices with limited energy budget. The energy consumption attack tries to consume the battery energy of a wireless device with repeated connection requests and shut down the wireless device by exhausting its energy budget. The proposed scheme blocks a connection request of the energy consumption attack in the middle, if the same connection request is repeated and its request result is failed continuously. In order to avoid the blocking of innocuous mistakes of normal users, the scheme gives another chance to allow connection request after a fixed blocking time. The scheme changes the blocking time adaptively by comparing the message arriving ate during non-blocking period and that during blocking period. Evaluation shows that the proposed defense scheme saves up to 94% energy consumption compared to the non-defense case.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.441-445
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• 2002

Three naphthalene glycosides (1-3), four flavonoids (4-7), and two galloyl glycosides (8-9) were isolated from the stem-bark of Juglans mandshurica (Juglandaceae). Their structures were determined by chemical and spectral means, including to 2D-NMR (COSY, HMQC, and HMBC) experiments. Amongst the isolated compounds, taxifolin (4) showed the most potent HIV-induced cytopethic activity against MT-4 cells with complete inhibitory concentration ($IC_{100}$) value of $25{\;}{\mu\textrm{g}}/ml$ and maximum cytotoxic concentration ($CC_{100}$) value of above $100{\;}{\mu\textrm{g}}/ml$. However, naphthalene glycosides (1-3), flavonoids (5-7)), and galloyl tannins (8-9) were inactive against anti-HIV-1 activity.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.160.2-160.2
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• 2003

When ginsenoside $R_{b1}$ and $R_{b2}$ were anaerobically incubated with human fecal microflora, these ginsenosides were metabolized to compound K. When ginsenoside $R_{g3}$ was anaerobically incubated with human fecal microflora, the ginsenoside $R_{g3}$ was metabolized it to ginsenoside $R_{h2}$. Among ginsenosides, compound K and 20(S)-ginsenoside $R_h2$ exhibited the most potent cyotoxicity against tumor cells: 50% cytotoxic concentrations of compound K in the media with and without fetal bovine serum (FBS) were 27.1 - 31.6 mM and0.1 - 0.6 mM, and those of 20(S)-ginsenoside $R_h2$ were 37.5 $\rightarrow$ 50 and 0.7 - 7.1 mM mM, respectively. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.199.2-199.2
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• 2003

The bioassay-guided fractionation of protective agents against sepsis-induced lethality from the root bark of Paeonia suffruticosa led to the isolation of ten known compounds: paeonol (1), 2,5-dihydroxy-4-methoxyacetophenone (2) methyl 3-hydroxy-4- methoxybenzoate (3), acetovanillone (4), benzoic acid (5), benzoylpaeoniflorin (6), paeonoside (7), paeoniflorin (8), oxypaeoniflorin (9) and apiopaeonoside (10). Among them, 4 exhibited the highest survival rate in a dose-dependent manner (100% with a dose of 30 mg/kg versus 16.7% for the control experiment) and showed reduction of plasma alanine aminotransferase (ALT) value on the in vivo assay model of sepsis induced by LPS/GalN.

• Journal of Life Science
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• v.21 no.7
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• pp.976-984
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• 2011

Total phenolic content was the highest in 60% ethanol extracts at 21.91 mg/g, and inhibitory activity against tyrosinase of 60% ethanol extracts was higher than ethanol extracts of other concentration. The inhibitory compounds against tyrosinase from Persimmon leaves were purified using Sephadex LH-20, MCI-gel CHP-20 column chromatography with gradient elution. Two purified compounds were isolated as a result. The chemical structures of each compound were determined and identified using $^1H$-NMR and $^{13}C$-NMR, FAB-Mass. The compounds were confirmed as (+)-gallocatechin and prodelphinidin B-3. The tyrosinase inhibitory activities of purified (+)-gallocatechin and prodelphinidin B-3 were 29.5 and 40.2%, respectively. The inhibitory activities of (+)-gallocatechin and prodelphinidin B-3 against melanin biosynthesis in melanoma cell were 32.5 and 46.7%. The safety of essence with tyrosinase inhibitory compounds from persimmon leaves was also assessed by various safety profiles. First, changes in pH (4.90~4.95) and viscosity (23,000~26,000 cP) was not detected for 60 days. Essence also showed stability against temperature and light for 60 days. All these findings suggest that extracts from persimmon leaves have a great potential as a cosmetical ingredient with a potent whitening effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1291-1296
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• 2006

This study was performed to determine the antimutagenic and anticancer effects of Fagopyrum esculentum Moenech noodles (FEMN) extracts using Ames test and cytotoxicity, respectively. FEMN made buckwheat wet noodles (BWN), buckwheat extruded noodles (BEN) and buckwheat dehydrated noodles (BDN) by 60% buckwheat flour and 70% buckwheat flour. The inhibitory effects of FEMN extracts on cell proliferation in A549, Hep3B, MCF-7, AGS and HeLa were investigated by SRB assay. The cytotoxic effects of FEMN against the cell lines with human lung carcinoma (A549), human gastric carcinoma (AGS), human hepatocellular carcinoma (Hep3B), human cervical adenocarcinoma (HeLa) and human breast adenocarcinoma (MCF-7) were inhibited with the increase of the extract concentration. The treatment of 1.0 mg/mL FEMN of 60% BEN extracts showed strong cytotoxicities of 74.7%, 75.3% and 70.5% against AGS, A549 and HeLa, respectively. The inhibition rate of 70% BWN of FEMN extracts in the S. Typhimurium TA100 strain showed 41% against the mutagenesis induced by MNNG. The inhibition rate of 70% BEN of FEMN extracts in the S. Typhimurium TA98 strain showed 45% against the mutagenesis induced by 4NQO.

• Natural Product Sciences
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• v.18 no.2
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• pp.97-101
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• 2012

Six lignan compounds, 1-(17,21-dihydroxyphenyl)-9-(12,13-dihydroxyphenyl)-1-nonanone (malabaricone C) (1), 7'-(3',4'-methylenedioxyphenyl)-8,8'-dimethyl-7-(3,4-dihydroxyphenyl)-butane (2), 7'-(3',4'-dimethoxyphenyl)-8,8'-dimethyl-7-(3-methoxy-4-hydroxyphenyl)-butane (3), 7-(4-hydroxy-3-methoxyphenyl)-7'-(3',4'-methylenedioxyphenyl)-8,8'-lignan-7-methyl ether (4), (+)-erythro-(7S,8R)-${\Delta}^{8^'}$-7-hydroxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan (5), and (+)-erythro-(7S,8R)-${\Delta}^{8^'}$-7-acetoxy-3,4,3',5'-tetramethoxy-8-O-4'-neolignan (6), were isolated from the seeds of Myristica fragrans. The chemical structures of these compounds were determined on the basis of spectroscopic analyses including 2D NMR. Compounds 1 - 6 were evaluated for their cytotoxic activity against the HL-60, MCF-7, and A549 cancer cell lines in in vitro.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.775-783
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• 2005

The ethanol extract of the peony root (Paeonia Lactiflora Pall, Paeoniaceae) as well as its major active components including gallic acid and methyl gallate were evaluated for their protective effects against free radical generation and lipid peroxidation. In addition, the protective effects against hydrogen peroxide-induced oxidative DNA damage in a mammalian cell line were examined. The ethanol extracts of the peony root (PREs) and its active constituents, gallic acid and methyl gallate, exhibited a significant free radical scavenging effect against 1,1-diphenyl-2-picryl hydrazine (DPPH) radical generation and had an inhibitory effect on lipid peroxidation, as measured by the level of malondialdehyde (MDA) formation. The PREs did not have any pro-oxidant effect. They strongly inhibited the hydrogen peroxide-induced DNA damage from NIH/3T3 fibroblasts, as assessed by single cell gel electrophoresis. Furthermore, the oral administration of 50% PRE (50% ethanol extract of peony root), gallic acid and methyl gallate potently inhibited the formation of micronucleated reticulocytes (MNRET) in the mouse peripheral blood induced by a $KBrO_3$ treatment in vivo. Therefore, PREs containing gallic acid and methyl gallate may be a useful antigenotoxic antioxidant by scavenging free radicals, inhibiting lipid peroxidation and protecting against oxidative DNA damage without exhibiting any pro-oxidant effect.