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Dive into the research topics where Seun-Ah Yang is active.

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Featured researches published by Seun-Ah Yang.


Natural Product Research | 2010

Comparative study of the chemical composition and antioxidant activity of six essential oils and their components

Seun-Ah Yang; Sang-Kyung Jeon; Eun-Jung Lee; Chang-Hyun Shim; In-Seon Lee

The antioxidant activities and the determined major components of six popular and commercially available herb essential oils, including lavender (Lavendular angustifolia), peppermint (Mentha piperita), rosemary (Rosmarius officinalis), lemon (Citrus limon), grapefruit (Citrus paradise), and frankincense (Boswellia carteri), were compared. The essential oils were analysed by GC–MS and their antioxidant activities were determined by testing free radical-scavenging capacity and lipid peroxidation in the linoleic acid system. The major components of the essential oils of lavender, peppermint, rosemary, lemon, grapefruit, and frankincense were linalyl acetate (28.2%), menthol (33.4%), 1,8-cineole (46.1%), limonene (64.5 and 94.2%), and p-menth-2-en-ol (34.5%), respectively. The highest DPPH radical-scavenging activity was obtained by the lavender essential oil and limonene, with RC50 values of 2.1 ± 0.23% and 2.1 ± 0.04%, respectively. Radical-scavenging activity against the ABTS radical was highest in peppermint essential oil (1.6 ± 0.09). Lavender oil was most effective for inhibiting linoleic acid peroxidation after 10 days.


Food Chemistry | 2013

Suppression of LPS-induced inflammatory activities by Rosmarinus officinalis L.

Mi-Hee Yu; Jun-Hyeok Choi; In-Gyeong Chae; Hyo-Gwon Im; Seun-Ah Yang; Kunal N. More; In-Seon Lee; Jinho Lee

Rosemary (Rosmarinus officinalis L.) has been used in folk medicine to treat headaches, epilepsy, poor circulation, and many other ailments. It was found that rosemary could act as a stimulant and mild analgesic and could reduce inflammation. However, the mechanisms underlying the anti-inflammatory effects of rosemary need more study to be established. Therefore, in this study, the effects of rosemary on the activation of nuclear factor kappa beta (NF-kB) and mitogen-activated protein kinases (MAPKs), the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and the production of nitric oxide (NO), prostaglandin E(2) (PGE(2)), and cytokine in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells were investigated. A methanol extract of rosemary and its hexane fraction reduced NO generation with an IC(50) of 2.75 and 2.83 μg/ml, respectively. Also, the methanol extract and the hexane fraction inhibited LPS-induced MAPKs and NF-kB activation associated with the inhibition of iNOS or COX-2 expression. LPS-induced production of PGE(2) and tumour necrosis factor-alpha (TNF-α) were blocked by rosemary. Rosemary extract and its hexane fraction are important for the prevention of phosphorylation of MAPKs, thereby blocking NF-kB activation, which in turn leads to decreased expression of iNOS and COX-2, thus preventing inflammation.


Korean Journal of Food Science and Technology | 2011

Quality Characteristics and Anti-proliferative Effects of Dropwort Extracts Fermented with Fructooligosaccarides on HepG2 Cells

Min-Ju Kim; Seun-Ah Yang; Jung-Hyun Park; Hyeok-Il Kim; Sam-Pin Lee

The quality characteristics and effects on the proliferation of human hepatoma HepG2 cells due to dropwort (Oenanthe javanica) extracts naturally fermented with fructooligosaccharides were investigated. Dropwort was fermented by steeping with the same weight of oligosaccaride at room temperature for 1 year, and then stored at 4 for 1 or 2 more years. During the fermentation periods, total flavonoid content, Hunter`s color (a value), and viable cell counts decreased, but reducing sugars including glucose and fructose increased. HepG2 cell proliferation was inhibited significantly by the three extracts, but no effects were observed on Chang cells. In particular, the dropwort extract fermented for 1 year showed the highest inhibitory effect. These results demonstrate that the quality characteristics and anti-proliferative effects of dropwort were affected by fermentation period. It is concluded that dropwort extract fermented for 1 year showed the highest functional properties and quality.


Food and Chemical Toxicology | 2014

Hepatoprotective effects of fermented field water-dropwort (Oenanthe javanica) extract and its major constituents.

Seun-Ah Yang; Yeon-Seop Jung; Seung-Jin Lee; Seung-Chun Park; Min-Ju Kim; Eun-Ju Lee; Hae-Jung Byun; Kwang-Hwan Jhee; Sam-Pin Lee

Dropwort (Oenanthe javanica) has been used for many years for the treatment of inflammatory conditions, including hepatitis. We investigated the protective effects of fermented field water-dropwort extract (FDE) on tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity in HepG2 cells and carbon tetrachloride (CCl4)-induced liver damage in rats. Pretreatment with FDE prior to the t-BHP treatment of HepG2 cells inhibited cell death and lactate dehydrogenase (LDH) leakage in a dose-dependent manner. In addition FDE significantly prevented the increase of hepatic enzyme markers (ALT, AST) in vivo. Moreover, FDE administration for 7 days significantly affected CYP2E1, CYP4A2, and PPARγ gene expressions. CYP2E1 and CYP4A2 gene expression in the liver, increased 2 and 22-fold by CCl4 administration, respectively, was attenuated to normal levels by pretreatment with FDE. PPARγ gene expression, completely blocked by CCl4 treatment, was increased by FDE pretreatment compared to normal control group. Histopathological examination of the livers also revealed that FDE reduced the incidence of liver lesions. Caffeic acid and chlorogenic acid were identified as major constituents of FDE. These results demonstrate the protective effects of FDE against hepatocytotoxicity induced by CCl4 and t-BHP in rats and HepG2 cells, thus indicating the potential of FDE as a therapeutic for acute liver diseases.


Korean Journal of Food Science and Technology | 2012

A Comparative Study of GABA, Glutamate Contents, Acetylcholinesterase Inhibition and Antiradical Activity of the Methanolic Extracts from 10 Edible Plants

Yeon-Seop Jung; Sungjin Park; Ji-Eun Kim; Seun-Ah Yang; Junghyun Park; Jung-Hyun Kim; Kwang-Hwan Jhee; Sam-Pin Lee; In-Seon Lee

In order to investigate the efficacies for cognitive function of edible plants, we measured the inhibitory effects of acetylcholinesterase(AChE) activity, radical scavenging activities, and the contents of GABA and glutamate in the plant extracts. Among the plant extracts, Schizandra chinensis contained the highest GABA 14.8 mg/g and the extracts of Cnidium officinale and Polygonum multiflorum also had a relatively high GABA. On the other hand, plant extracts except, Acorus gramineus, showed similar glutamate contents. S. chinensis, Hovenia dulcis, Thuja orientalis, and Eleutherococcus senticosus exhibited high inhibition against AChE activities at about 18-33% at 1 mg/mL. In addition, strong radical scavenging activities were also detected in those extracts which showed high AChE inhibition. Taken together, H. dulcis, T. orientalis, E. senticosus, and S. chinensis could be effective resources for enhancing cognitive function. Further, it was suggested that the AChE inhibitory activities of plant extracts might be related to antioxidative activity.


Bioscience, Biotechnology, and Biochemistry | 2015

Tricin derivatives as anti-inflammatory and anti-allergic constituents from the aerial part of Zizania latifolia

Seung-Su Lee; Yoon-Su Baek; Cheong-Su Eun; Mi-Hee Yu; Nam-In Baek; Dae Kyun Chung; Myun-Ho Bang; Seun-Ah Yang

Methanol extract of Zizania latifolia was partitioned with EtOAc, n-BuOH, and H2O. From the EtOAc layers, a new flavonolignan along with a known flavone and three known flavonolignans, tricin (1), salcolin A (2), salcolin B (3), and salcolin C (4), were isolated through repeated silica gel and ODS column chromatography. The chemical structure of the new flavonolignan was determined to be tricin-4′-O-[erythro-β-guaiacyl-(7″-O-methyl)-glyceryl] ether and was named salcolin D (5) based on physicochemical and spectroscopic data, including FT-NMR and ESI-MS. All compounds were isolated for the first time from this plant. Compounds 2–5, tricin derivatives, all exhibited higher anti-inflammatory and anti-allergy activities than tricin. In particular, salcolin D (5) was shown to have the strongest inhibitory activity against LPS-induced NO production in RAW 264.7 cells as well as β-hexosaminidase release in IgE-sensitized RBL-2H3 cells. These results suggest that the presence of tricin derivatives conveys allergy and inflammation treatment ability to Z. latifolia. Graphical Abstract Chemical structures of the isolated compounds 1–5 from the Z. latifolia and Key gHMBC correlations for compound 5


Bioscience, Biotechnology, and Biochemistry | 2012

Inhibitory Effects of Actinidiamide from Actinidia polygama on Allergy and Inflammation

Myun-Ho Bang; In-Gyeong Chae; Eun-Ju Lee; Nam-In Baek; Yoon-Su Baek; Dae-Young Lee; In-Seon Lee; Sam-Pin Lee; Seun-Ah Yang

Actinidia polygama Max. was subjected to supercritical fluid extraction (SFE), and the resulting ethanol extract of marc (SFEM) was subjected to sequential fractionation with various solvents. Each extract and fraction was assayed for anti-inflammatory effect. The ethyl acetate fraction (EtOAc) contained the highest level (70.8% inhibition) of anti-inflammatory activity. In order to identify the active constituents, the EtOAc fraction was further fractionated by silica gel and ODS column chromatography. By activity-guided fractionation, an active ceramide was identified as the anti-inflammatory component, and its structure was determined by NMR and MS analysis. The novel ceramide was named actinidiamide, and was found significantly to inhibit nitric oxide (NO) production (30.6% inhibition at 1 μg/mL) in lipopolysaccaride (LPS)-stimulated RAW 264.7 cells and β-hexosaminidase release (91.8% inhibition at 1 μg/mL) in IgE-sensitized RBL-2H3 cells. Thus the presence of actinidiamide conveys allergy and inflammation treatment ability to A. polygama.


Journal of Life Science | 2008

Effects of Aralia continentalis Kitagawa on Antiplatelet and Antioxidative Activities.

Seun-Ah Yang; Nam-Kyung Im; Kwang-Hwan Jhee; In-Seon Lee

단삼 메탄올 추출물의 항혈전 및 항산화 효과를 확인하기 위하여 혈소판의 응고 억제효과, 혈장응고시간의 연장, 혈전용해 활성으로 항혈전 효과를 고찰하였으며 DPPH radical 소거능을 측정하여 항산화 효과를 검토하였다. 그 결과, 단삼의 메탄올 추출물은 항혈전과 항산화에 효과가 있는 것으로 나타났다. 이 추출물은 ...


Food Science and Biotechnology | 2017

Inhibitory effect of Zizania latifolia chloroform fraction on allergy-related mediator production in RBL-2H3 cells

Eun-Jung Lee; Mi-Hee Yu; Coralia V. Garcia; Kwang-Hwan Jhee; Seun-Ah Yang

Zizania latifolia exhibits anti-inflammatory and anti-allergic effects; however, the mechanisms behind these effects are unknown. Here the ethanol extract of Z. latifolia was partitioned using hexane, chloroform, ethyl acetate, butanol, and water. Subsequently, the anti-allergic effects of these fractions were evaluated in vitro. The results showed that the chloroform fraction of Z. latifolia inhibited the release of β-hexosaminidase and tumor necrosis factor (TNF-α) from RBL-2H3 cells stimulated with dinitrophenyl-bovine serum albumin (DNP-BSA). In addition, this fraction suppressed the expression of cyclooxygenase-2 (COX-2) and inhibited the activation of mitogen-activated protein kinases (MAPKs). The results obtained suggest that the chloroform fraction of Z. latifolia inhibited mast cell-mediated allergic inflammatory responses.


Journal of Life Science | 2016

Anti-oxidant and Anti-inflammatory Activities of Barley Sprout Extract

Cheong-Su Eun; E.A. Hwang; Syng-Ook Lee; Seun-Ah Yang; Mi-Hee Yu

Barley (Hardeum vulgare L.) sprout has received much attention in recent years as a functional food in many countries, especially in Korea and Japan. It has been reported that barley sprouts are com-prised of 52.6% polysaccharides, 34.1% proteins, and 4.97% fats, along with a variety of vitamins, min-erals, and polyphenols. The purpose of this study was to assess the anti-oxidant and anti-in-flammatory activities of the ethanol extracts of barley sprouts. We examined the inhibitory effect of barley sprout extracts (BSE) on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, and nitric oxide (NO), prostaglandin EBarley (Hardeum vulgare L.) sprout has received much attention in recent years as a functional food in many countries, especially in Korea and Japan. It has been reported that barley sprouts are comprised of 52.6% polysaccharides, 34.1% proteins, and 4.97% fats, along with a variety of vitamins, minerals, and polyphenols. The purpose of this study was to assess the anti-oxidant and anti-inflammatory activities of the ethanol extracts of barley sprouts. We examined the inhibitory effect of barley sprout extracts (BSE) on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, and nitric oxide (NO), prostaglandin E₂ (PGE₂) and cytokine production in lipopolysaccharide (LPS)-stimulated RAW 264.7 mouse macrophage cells. BSE contains high amounts of phenolics and flavonoids and exhibits potent anti-oxidative activity, as depicted by the DPPH radical- scavenging experiment. The concentration of total phenols was 17.55 μg/ml, and flavonoids, 13.98 μg/ml. We also investigated the anti-inflammatory activities of BSE in LPS-stimulated RAW 264.7 cells. Tumor necrosis factor-alpha and PGE2 production, which had increased as a result of treatment with LPS, were significantly inhibited by BSE in a dose-dependent manner. BSE also significantly suppressed LPS-induced production of NO, and this was accompanied by a decrease in the expression of the iNOS and COX-2 proteins. These results indicate that barley sprouts may be a highly valuable natural product owing to its high-quality functional components as well as its anti-oxidant and anti- inflammatory activities.

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Kwang-Hwan Jhee

Kumoh National Institute of Technology

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Hyun-Nam Cho

Kumoh National Institute of Technology

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Hae-Jung Byun

Kumoh National Institute of Technology

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