• Natural Product Sciences
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• v.5 no.4
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• pp.165-171
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• 1999

Since reactive oxygen species (ROS) play an important role in carcinogenesis and other several human diseases, antioxidants present in consumable fruits, vegetables, and beverages have received considerable attention as cancer chemopreventive agents. Thus, in order to identify antioxidants in plant extracts, potential activity was assessed by determining with inhibition of a xanthine/xanthine oxidase assay system. Approximately 170 plant extracts of Korean herbal medicines were primarily evaluated for the potential of antioxidant activity. As a result, 13 plant extracts were found to be active $(IC_{50}$<$100\;{\mu}g/ml)$. Especially, Juncus effusus, Selaginella tamariscina, Pueraria thunbergiana and Sedum albroseum showed strong inhibitory activity in this process. Further studies for the identification of active principles from these active lead plant extracts might be warranted.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1479-1484
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• 2008

Protein tyrosine phosphatase (PTP) 1B is the superfamily of PTPs and a negative regulator of multiple receptor tyrosine kinases (RTKs). Inhibition of protein tyrosine phosphatase 1B (PTP1B) has been proposed as a strategy for the treatment of type 2 diabetes and obesity. Recently, it has been reported that amentoflavone, a biflavonoid extracted from Selaginella tamariscina, inhibited PTP1B. In the present study, docking model between amentoflavone and PTP1B was determined using automated docking study. Based on this docking model and the interactions between the known inhibitors and PTP1B, we determined multiple pharmacophore maps which consisted of five features, two hydrogen bonding acceptors, two hydrogen bonding donors, and one lipophilic. Using receptor-oriented pharmacophore-based in silico screening, we searched the biflavonoid database including 40 naturally occurring biflavonoids. From these results, it can be proposed that two biflavonoids, sumaflavone and tetrahydroamentoflavone can be potent allosteric inhibitors, and the linkage at 5',8''-position of two flavones and a hydroxyl group at 4'-position are the critical factors for their allosteric inhibition. This study will be helpful to understand the mechanism of allosteric inhibition of PTP1B by biflavonoids and give insights to develop potent inhibitors of PTP1B.

• Korean Journal of Pharmacognosy
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• v.33 no.1 s.128
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• pp.35-41
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• 2002

The MeOH ext., $CH_2Cl_2$ Frac., EtOAc Frac., n-BuOH Frac., and $H_2O$ Frac. of 23 Korean medicinal herbs were prepared and were tested the inhibitory effects on Cytochrome P450 (Cyp) 1A1/2, 2B1/2, 2E1. Among the tested samples, the extracts of Selaginella tamariscina, Euonymus alatus, Salvia miltiorhiza, Angelica acutiloba, Rheum palmatum, Paeonia moutan, Scutellaria barbata, Tribulus terrestris, Hedyotis diffusa, Curcuma zedoaria, Rehmania glutinosa, Trogopterus xanthipes, Melandryum firmum, Achyranthes bidentata, Leonurus sibricus, Panax ginseng, Paeonia lactiflora, Poncirus trifoliata, Cnidium officinale, Cyperus rotundus, Corydalis ternata showed significant inhibitory effects on Cyp 1A1/2, 2B1/2, 2E1. The $IC_{50}$ values of those extracts were found to be below $50\;{\mu}g/ml$.

• Korean Journal of Pharmacognosy
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• v.35 no.1 s.136
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• pp.28-34
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• 2004

DNA damage induced by reactive oxygen species (ROS) seems to play an important role in the induction of mutation and cancer. Hydrogen peroxide $(H_2O_2)$ has been shown to induce a variety of genetic alterations, probably by the generation of hydroxyl radicals via Fenton reaction. In this study, we examined the ability of medicinal herbs in the suppression of $H_2O_2$-induced mutagenesis. Human fibroblast GM00637 cells were treated with $H_2O_2$ in the presence or absence of medicinal herbs, and $H_2O_2$-induced mutant frequency was measured at the hypoxanthine guanine phosphoribosyl transferase (HPRT) locus. Treatment of cells with various doses of $H_2O_2$ caused a significant increase of the HPRT mutant frequency. However, pretreatment of cells with several medicinal herbs reduced $H_2O_2$-induced mutant frequency. The strong antimutagenic effects were observed from the methylene chloride and ethyl acetate fractions of Selaginella tamariscina, Panax ginseng, and Angelica acutiloba; ethyl acetate fractions of Rehmania glutinosa, Leonurus sibiricus, Curcuma zedoaria and Commiphora molmol; butanol fractions of Scutellaria barbata, Tribulus terrestris, Curcuma zedoaria, Cyperus rotundus and Carthamus tinctorius, which were more than 60% inhibition of $H_2O_2$-induced mutant frequency at the HPRT locus.

• The Korean Journal of Ecology
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• v.23 no.3
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• pp.217-221
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• 2000

The vegetation of Maemul, Somaemul and Eoyu islets in Tongyeong-si was investigated from September, 1996 through August, 1997. In order to analyze the vegetation of this islets, synthesis table, actual vegetation map were prepared. The predominant species of the islets was Camellia japonica. and the vegetation in this study area was classfied into 4 communties (included 1 afforestation) and 7 subcommunities 1 . Camellia japonica community 1) Typical subcommunity 2) Machilus thunbergii subcommunity 3) Castanopsis cuspidata var, thunbergii subcommunity 4) Ligustrum obtusifolium subcommunity 5) Carpinus coreana subcommunity 6) Selaginella tamariscina subcommunity 7) Pinus thunbergii subcommunity 2. Pinus thunbergii community 3. Alnus firma afforestation 4. Miscanthus sinensis var. purpurascens community.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.185-192
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• 2007

The different parts of 8 edible and medicinal ferns were extracted with 80% ethanol and the bioactive substances and antioxidant activities were investigated. Total polyphenol content was highest in Cyrtomium fortunei rhizome ($57.32mg{\cdot}g^{-1}$) and followed by C. fortunei root, Pyrrosia lingua aerial part and Onoclea sensibilis var. interrupta aerial part. Total flavonoid contents ranged from 1.95 (Onoclea sensibilis var. interrupta rhizome) to $27.51mg{\cdot}g^{-1}$ (O. sensibilis var. interrupta aerial part). Among the samples tested, C. fortunei root and rhizome were found to be most effective in both DPPH and ABTS radical scavenging assay. Except in Selaginella tamariscina underground part and Osmunda japonica aerial part, most of the tested samples showed strong potential (above 87%) in inhibition rate on linoleic acid oxidation.

• Natural Product Sciences
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• v.25 no.2
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• pp.103-110
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• 2019

We investigated the anti-inflammatory effect of Pyunkang-tang extract (PGT), a complex herbal extract based on traditional Chinese medicine that is used in Korea for controlling diverse pulmonary diseases, on cigarette smoke-induced pulmonary pathology in a rat model of chronic obstructive pulmonary disease (COPD). The constituents of PGT were Lonicerae japonica, Liriope platyphylla, Adenophora triphilla, Xantium strumarinum, Selaginella tamariscina and Rehmannia glutinosa. Rats were exposed by inhalation to a mixture of cigarette smoke extract (CSE) and sulfur dioxide for three weeks to induce COPD-like pulmonary inflammation. PGT was administered orally to rats and pathological changes to the pulmonary system were examined in each group of animals through measurement of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin-6 (IL-6) levels in bronchoalveolar lavage fluid (BALF) at 21 days post-CSE treatment. The effect of PGT on the hypersecretion of pulmonary mucin in rats was assessed by quantification of the amount of mucus secreted and by examining histopathologic changes in tracheal epithelium. Confluent NCI-H292 cells were pretreated with PGT for 30 min and then stimulated with CSE plus PMA (phorbol 12-myristate 13-acetate), for 24 h. The MUC5AC mucin gene expression was measured by RT-PCR. Production of MUC5AC mucin protein was measured by ELISA. The results were as follows: (1) PGT inhibited CSE-induced pulmonary inflammation as shown by decreased TNF-${\alpha}$ and IL-6 levels in BALF; (2) PGT inhibited the hypersecretion of pulmonary mucin and normalized the increased amount of mucosubstances in goblet cells of the CSE-induced COPD rat model; (3) PGT inhibited CSE-induced MUC5AC mucin production and gene expression in vitro in NCI-H292 cells, a human airway epithelial cell line. These results suggest that PGT might regulate the inflammatory aspects of COPD in a rat model.