• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.285-290
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• 1997

Previously, a 50% aqueous methanol extract of Galla rhois was shown to be the most potent tyrosinase inhibition activity with an {TEX}$IC_{50}${/TEX}(the concentration causing 50% inhibition of tyrosinase activity) of 0.2mg/ml of 205 crude drug extracts. To isolate tyrosinase inhibitors, the methanol extract was evaporated to a small volume in vacuo, and then partitioned stepwise with benzene and ethyl acetate(EtOAc). the EtOAc fraction was solubilized in 10% MeOH solution, and then fractionated successively by Diaion HP-20 and Sephadex LH-20 column chromatography, and preparative HPLC. Three phenolic compounds were isolated, and characterized as gallic acid(GA), methyl gallate(MG) and 1,2,3,4,6-penta-O-galloyl-$\beta$-D-glucose(PGG) by UV, IR, {TEX}${1}^H${/TEX}-&{TEX}${13}^C${/TEX}-NMR, and FAB-MS spectroscopy, PGG({TEX}$IC_{50}${/TEX}=50$\mu\textrm{g}$/ml) showed a considerable inhibitory effect against mushroom tyrosinase, while GA({TEX}$IC_{50}${/TEX}=1.6mg/ml) and MG({TEX}$IC_{50}${/TEX}=234$\mu\textrm{g}$/ml) did not show an appreciable effect. Meanwhile, MG inhibited greatly melanogenesis in a murine melanocyte cell line, Mel-Ab. MG and PGG showed typical noncompetitive inhibition patterns against mushroom tyrosinase. These results suggest that PGG and MG may be potentially useful as either anti-browning or anti-melanogenic agents in foods and cosmetics.

• BMB Reports
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• v.43 no.4
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• pp.268-272
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• 2010

Aldo-keto reductase family 1 B10 (AKR1B10) is a member of the NADPH-dependent aldo-keto reductase (AKR) superfamily, and has been considered to be a potential cancer therapeutic target. Total extract from the bark of Rhus verniciflua (Toxicodendron vernicifluum (Stokes)) showed AKR1B10 inhibitory activity. To identify the active compounds from R. verniciflua responsible for AKR1B10 inhibition, nine compounds were isolated via bioactivity-guided isolation and tested for their effects against recombinant human AKR1B10 (rhAKR1B10). Results showed that butein, isolated from the ethyl acetate fraction, was most able to inhibit rhAKR1B10. The inhibitory rate of butein against rhAKR1B10 was 42.86% at $1\;{\mu}M$ with an IC50 value of $1.47\;{\mu}M$, and enzyme kinetic analysis revealed its inhibition mode to be uncompetitive.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.564-568
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• 2007

In this study, the ethanolic extracts of 40 species of traditional herbal medicines were examined for their antimicrobial activities against Clostridium difficile. Among the 43 screened traditional herbal medicines, Achyranthes Japonica Nakai (AJN), Siegesbeckia glabrescens Makino, and Phelloedendron amurense Ruprecht showed antimicrobial activities greater than 90% at a concentration of 500 ppm. According to the minimum inhibitory concentration (MIC) test the ethyl acetate soluble fraction of the AJN ethanolic extracts (AJNEA) showed the highest growth inhibitory activity against C. difficile, with a MIC of $625{\mu}g/mL$. In addition, the effect of AJNEA on the growth of lactic acid bacteria was investigated. AJNEA did not inhibit the growth of the tested Bifidobacterium spp. or Lactobacillus spp., with the exception of B. longum, Streptococcus thermophilus, and L. helveticus. These results indicate that AJNEA can be utilized as a potential antimicrobial agent against C. difficile related disease.

• Korean Journal of Pharmacognosy
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• v.37 no.4 s.147
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• pp.235-240
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• 2006

We investigated the antioxidant activities such as DPPH radical scavenging capacity, xanthine oxidase inhibitory activity, and superoxide radical scavenging capacity of the aqueous EtOH extract and its solvent fractions of Artemisia scoparia. The ethyl acetate fraction showed high antioxidant activity, compared to positive controls such as ascorbic acid, butylated hydroxy anisole (BHA), trolox, and allopurinol in these assay systems. Moreover, we examined the inhibitory effect of solvent fractions of A. scoparia on the production of pro-inflammatory factors that the nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and prostaglandin E2 $(PGE_2)$ production activated with LPS $(1{\mu}g/ml)$ in murine macrophage cell line RAW264.7. The amounts of protein levels were determined by immunoblottting. Tn the sequential fractions of hexane and dichloromethane inhibited the NO and $PGE_2$ production and the protein level of iNOS and COX-2. These results suggest that A. scoparia may have anti-inflammatory activity through the antioxidant activity and inhibition of pro-inflammatory factors.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.568-575
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• 2018

In order to discover lifespan-extending compounds made from natural resources, activity-guided fractionation of Zingiber officinale Roscoe (Zingiberaceae) ethanol extract was performed using the Caenorhabditis elegans (C. elegans) model system. The compound 6-gingerol was isolated from the most active ethyl acetate soluble fraction, and showed potent longevity-promoting activity. It also elevated the survival rate of worms against stressful environment including thermal, osmotic, and oxidative conditions. Additionally, 6-gingerol elevated the antioxidant enzyme activities of C. elegans, and showed a dose-depend reduction of intracellular reactive oxygen species (ROS) accumulation in worms. Further studies demonstrated that the increased stress tolerance of 6-gingerol-mediated worms could result from the promotion of stress resistance proteins such as heat shock protein (HSP-16.2) and superoxide dismutase (SOD-3). The lipofuscin levels in 6-gingerol treated intestinal worms were decreased in comparison to the control group. No significant 6-gingerol-related changes, including growth, food intake, reproduction, and movement were noted. These results suggest that 6-gingerol exerted longevity-promoting activities independently of these factors and could extend the human lifespan.

• Korean Journal of Medicinal Crop Science
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• v.14 no.5
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• pp.273-277
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• 2006

Three stigmastane-type sterols and one ergostane-type sterol were isolated from the ethyl acetate soluble fraction of the aerial parts of Artemisia princeps Pampanini (Sajuarissuk). From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as $stigmasta-5,22-dien-3,{\beta}-ol (stigmasterol, 1),stigmast-5-en-3{\beta}-ol({\beta}-sitosterol,2), 5{\beta},8{\beta}-epidioxy-5{\beta},8{\beta}-ergosta-6,22-dien-3{\beta}-ol(ergosterol peroxide, 3),\;and\;{\beta}-sitosterol\;3-O-{\beta}D-glucopyranoside(daucosterol,4)$.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.450-455
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• 1998

Pine has been known as a traditional medicinal plant and as showing a physically beneficial function to a human being. Therefore, this study was performed to investigate the physiological activities of main pine neddles. Ethanol extracts from pinus needles did net exhibit any mutagenicity. On the contrary, inhibitory effects of ethanol extract were observed on mutagenicity induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), 4-nitroquinoline-1-oxide (4NQO), 3-amino-1,4-dimethyl-5H-pyrido-(4,3-b)indol (Trp-P-1) and benzo(a)pyrene $(B({\alpha})P)$ using Salmonella typhimurium reversion assay. On direct-acting mutagen (MNNG, 4NQO) and indirect-acting mutagen (Trp-P-1, $(B({\alpha})P)$, we observed higher inhibitory effect. Stepwise fractionation of the ethanol extract was done by using ether, chloroform, ethyl acetate, butanol and water to obtain effective fraction. Among them, water fractions $(100\;{\mu}g/plate)$ of Pinus thunbergii, Pinus rigida, Pinus densiflora and Pinus koraiensis showed high inhibition of 91.65%, 94.7%, 84.22% and 79.02%, respectively, on the mutagenicity of MNNG in Salmonella typhimurium TA100.

• Natural Product Sciences
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• v.26 no.3
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• pp.200-206
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• 2020

The ability of the total extract from Physalis angulata; three fractions after partitioning with n-hexane, ethyl acetate (TBE), and water; and four withanolides (compounds 1 - 4) to phosphorylate 5'-adenosine monophosphate-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in HepG2 cells was evaluated. The TBE fraction (50 ㎍/mL) activated p-ACC and p-AMPK expression most strongly. Compounds 1 - 4 (10 μM) upregulated p-ACC expression at different levels. Compound 4 induced the most significant changes in p-AMPK expression, followed by 1 and 2. Sterol regulatory element-binding proteins (SREBPs) play a functional role in the transcriptional regulation of the lipogenic pathway, including fatty acid synthase (FAS) and ACC. The effects of compounds 2 and 4 (10 μM) on FAS and SREBP-1c expression under high glucose conditions (30 mM) in HepG2 cells were evaluated further. Both dose-dependently inhibited FAS and SREBP-1c expression as well as lipid accumulation (1 - 10 μM) were compared to high-concentration glucose control, which upregulated FAS and SREBP-1c. These results suggest that compounds 2 and 4 upregulate AMPK, suppress FAS and SREBP-1c, and have potential effects on glucose and lipid metabolism.

• Journal of Applied Biological Chemistry
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• v.58 no.2
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• pp.109-112
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• 2015

Fruits of Rhus parviflora were extracted with 80% aqueous methanol (MeOH), and the concentrated extract was partitioned using ethyl acetate (EtOAc), n-butanol (n-BuOH), and $H_2O$, successively. Purification of EtOAc fraction led to isolation of fifteen polyphenols of which structures were identified by spectroscopic methods including 2D-NMR. Most compounds apart from compound 10 inhibited low density lipoproteinoxidation within $IC_{50}$ value of $10{\mu}M$. Among compounds, taxifolin (2), quercetin 3-O-${\alpha}$-L-rhamnopyranoside (13), agathisflavone (5) sulfuretin (4), and aureusidin (3) showed $IC_{50}$ values 0.9, 0.8, 5.8, 2.9, and $2.4{\mu}M$ which were of highly significant in comparison positive control butylated hydroxytoluene with $IC_{50}$ value of $2.1{\mu}M$. The results indicate fruits of R. parviflora as a source of antihypercholesterolemic compounds.

• Journal of Applied Biological Chemistry
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• v.61 no.2
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• pp.131-134
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• 2018

The stem of Chrysanthemum morifolium, 'Baekma', were repeatedly extracted with 80% aqueous MeOH and the concentrates was partitioned into ethyl acetate (EtOAc), n-butyl alcohol and $H_2O$ fraction. The repeated silica gel and octadecyl silica gel column chromatographies for the EtOAc fractions led to isolation of two glycosyl glycerides. The chemical structures of the compounds were determined as (2S)-1-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-2,3-dilinoleoylglycerol (1) and (2S)-1-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-2,3-dipalmitoylglycerol (2) based on spectroscopic data anlyses including nuclear magnetic resonance, mass sperctrometry, and infrared spectrometry and gas chromatography mass spectrometry.