Byong-Tae Jeon

Konkuk University, Sŏul, Seoul, South Korea

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Publications (55)74.78 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: This study was undertaken to evaluate the antioxidant potential and protective effects of Celosia cristata L. (Family: Amaranthaceae) flower (CCF) extracts on tert-butyl-hydroperoxide (t-BHP)-induced oxidative damage in the hepatocytes of Chang cells and rat livers. In vitro, CCF extracts exhibited protective effect through their radical scavenging ability to enhance cell viability, prevent reactive oxygen species (ROS) generation, and inhibit mitochondrial membrane depolarisation in t-BHP-induced hepatotoxicity in Chang cells. In vivo, oral feeding of CCF (100mg and 500mg/kg of body weight) to rats for five consecutive days before a single dose of t-BHP (2mmol/kg, i.p.) showed a significant (p<0.05) protective effect by lowering serum levels of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT). The extract decreased the hepatic levels of lipid peroxidation (MDA) and serum level of triglyceride (TG) against t-BHP-induced oxidative stress. These results indicate that CCF extract prevented oxidative stress-induced liver injury by enhancing hepatocyte antioxidant abilities.
    Food chemistry. 02/2015; 168C:572-579.
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    ABSTRACT: α-Glucosidase inhibitors are important agents for decreasing postprandial hyperglycemia. The current study examined the inhibitory effects of octaphlorethol A (OPA) isolated from Ishige foliacea, a brown alga, on α-glucosidase, and analyzed the inhibitor's binding modes using the crystal structure of α-glucosidase. The effects of OPA on postprandial blood glucose levels after meals were also investigated. The IC50 value of OPA against α-glucosidase was 0.11 mM, which is higher than that of the commercial inhibitor acarbose. For further insights, we predicted the 3D structure of α-glucosidase and used a docking algorithm to simulate binding between α-glucosidase and OPA. These molecular modeling studies were successful, and indicated that OPA interacts with Phe575, His600, Arg526, Met444, Asp542, Tyr605, Ser448, Asp203, Lys480, and Phe450. Furthermore, increases in postprandial blood glucose levels were significantly suppressed in the OPA-treated group compared with those in the streptozotocin-induced diabetic or normal mice. Additionally, the area under the curve was significantly reduced following OPA administration (907 versus 1034 mg h dL(-1)) in the diabetic mice, along with a delay in the absorption of dietary carbohydrates. Collectively, these results indicated that OPA is a potent inhibitor of α-glucosidase, and shows potential to be used as an anti-diabetic agent.
    Food & Function 08/2014; · 2.69 Impact Factor
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    ABSTRACT: Hyperglycemia-induced oxidative stress accelerates endothelial cell dysfunctions, which cause various complications of diabetes. The protective effects of 6,6'-bieckol (BEK), one of phlorotannin compound purified from Ecklonia cava against high-glucose-induced oxidative stress was investigated using human umbilical vein endothelial cells (HUVECs), which is susceptible to oxidative stress. High glucose (30 mM) treatment induced HUVECs' cell death, but BEK, at concentration 10 or 50 μg/ml, significantly inhibited the high-glucose-induced cytotoxicity. Furthermore, treatment with BEK dose-dependently decreased thiobarbituric acid reactive substances (TBARS), intracellular reactive oxygen species (ROS) generation, and nitric oxide level increased by high glucose. In addition, high glucose levels induced the overexpressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor-kappa B (NF-κB) proteins in HUVECs, but BEK treatment reduced the overexpressions of these proteins. These findings indicate that BEK is a potential therapeutic agent that will prevent diabetic endothelial dysfunction and related complications.
    Applied biochemistry and biotechnology. 08/2014;
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    ABSTRACT: In this study, we investigated the anticancer activity of a newly isolated compound from Acer tegmentosum Maxim (ATM) in HepG2 cells. This compound was isolated by reverse-phase high-performance liquid chromatography (RP-HPLC) in a butanol-soluble fraction, which was shown to have the strongest anticancer activity. The isolated compound was identified as salidroside using multiple nuclear magnetic resonance (NMR) techniques, including 1H, 13C, correlated spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), and heteronuclear multiple bond correlation (HMBC), as well as electrospray ionization mass spectroscopy (ESI/MS). The activity of salidroside was evaluated in HepG2 cells by analyzing cell proliferation, cell cycle distribution, Hoechst 33342 staining, and western blots of apoptotic regulatory proteins. The results show that salidroside, an anticancer compound from ATM, exhibits strong apoptotic activity in HepG2 cells. Therefore, ATM extracts could be used as chemotherapeutic agent to induce apoptosis in hepatoblastoma cells.
    PROCESS BIOCHEMISTRY 06/2014; · 2.41 Impact Factor
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    ABSTRACT: In this study, Haliotis discus hannai (H. discus hannai) fermentation was attempted with Cordyceps militaris (C. militaris) mycelia using a solid culture. We tried to ferment H. discus hannai to determine the optimal conditions fermentation with regards to its anti-inflammatory effects. The extracts of H. discus hannai fermented with C. militaris mycelia (HFCM-5) showed higher nitric oxide inhibitory effects than H. discus hannai and C. militaris alone. HFCM-5 also decreased pro-inflammatory cytokines, TNF-α and IL-6 in a dose-dependent manner. HFCM-5 did not affect the MyD88-dependent pathway, but decreased phosphorylation of IRF3 and STAT1 which are involved in TRIF-dependent pathway. Taken together, our results suggest that HFCM-5 exerts its anti-inflammatory effects via TRIF signaling pathway and could potentially be used as a functional food in the regulation of inflammation.
    Fish &amp Shellfish Immunology 01/2014; · 2.96 Impact Factor
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    ABSTRACT: Various biological effects have been reported for sulfated chitosan oligosaccharides, but the molecular mechanisms of action of their anti-inflammatory effects are still unknown. This study aimed to evaluate the anti-inflammatory effects of sulfated chitosan oligosaccharides and to elucidate the possible mechanisms of action. The results showed that pretreated low molecular weight sulfated chitosan oligosaccharides inhibited the production of nitric oxide (NO) and inflammatory cytokines such as IL-6 and TNF-α in lipopolysaccharide (LPS)-activated RAW264.7 cells. The sulfated chitosan oligosaccharides also suppressed inducible nitric oxide synthase (iNOS), phosphorylation of JNK and translocation of p65, a subunit of NF-κB, into the nucleus by inhibiting degradation of IκB-α. Our investigation suggests sulfated chitosan oligosaccharides inhibit IL-6/TNF-α in LPS-induced macrophages, regulated by mitogen-activated protein kinases (MAPKs) pathways dependent on NF-κB activation.
    Molecules (Basel, Switzerland). 01/2014; 19(11):18232-47.
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    ABSTRACT: Chitin is a natural polysaccharide of major importance. This biopolymer is synthesized by an enormous number of living organisms; considering the amount of chitin produced annually in the world, it is the most abundant polymer after cellulose. The most important derivative of chitin is chitosan, obtained by partial deacetylation of chitin under alkaline conditions or by enzymatic hydrolysis. Chitin and chitosan are known to have important functional activities but poor solubility makes them difficult to use in food and biomedicinal applications. Chitooligosaccharides (COS) are the degraded products of chitosan or chitin prepared by enzymatic or chemical hydrolysis of chitosan. The greater solubility and low viscosity of COS have attracted the interest of many researchers to utilize COS and their derivatives for various biomedical applications. In light of the recent interest in the biomedical applications of chitin, chitosan, and their derivatives, this review focuses on the preparation and biological activities of chitin, chitosan, COS, and their derivatives.
    BioMed research international. 01/2014; 2014:654913.
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    ABSTRACT: In this study, the antioxidant properties of Trapa japonica pericarp extracts were evaluated through several biochemical assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH), Alkyl radical scavenging activity, hydroxyl radical scavenging, ferric reducing antioxidant power (FRAP) assay, ABTS radical scavenging activity and oxygen radical absorbance capacity (ORAC). The antioxidant activities were compared with other natural and synthetic antioxidants. The results showed that higher radical scavenging activity and antioxidant capacity in FRAP than those of vitamin C as a positive control. Trapa japonica pericarp extracts have antioxidant properties through its ability to prevent tert-butylhydroperoxide (t-BHP)-induced toxicity which enhance the cell viability, reduce reactive oxygen species (ROS) production, inhibits of oxidative damage and mitochondria dysfunction in Chang liver cells. Therefore, based on these finding, it seems reasonable to suggest that Trapa japonica pericarp extracts has the potential to protect liver against t-BHP-induced cell damage and should be considered as a potential functional food.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 11/2013; · 2.99 Impact Factor
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    ABSTRACT: A novel anticancer peptide was purified from Crassostrea gigas (C. gigas) and was investigated for its cytotoxic activity. To prepare the peptide, eight proteases were employed for enzymatic hydrolysis. Flavourzyme hydrolysate, which showed clearly superior cytotoxic activity on prostate cancer cells, was further purified using a membrane system and consecutive chromatographic methods. Finally, a novel anticancer peptide was obtained, and the sequence was partially purified as His-Phe-Asn-Ile-Gly-Asn-Arg-Cys-Leu-Cys at N-terminal position. The peptide purified from C. gigas effectively induced cell death on prostate, breast and lung cancer cells but not on normal liver cells. This is the first report of an anticancer peptide derived from the enzymatic hydrolysates of C. gigas.
    Journal of Agricultural and Food Chemistry 11/2013; · 3.11 Impact Factor
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    ABSTRACT: A peptide was synthesized on the basis of our previous study from solid phase peptide synthesis using ASP48S (Peptron Inc) and identified by the reverse phase high-performance liquid chromatography (HPLC) using a Vydac Everest C18 column. The molecular mass of the peptide found to be 693.90 Da, and the amino acid sequences of the peptide was Trp-Tyr-Pro-Ala-Ala-Pro. The purpose of this study was to evaluate antioxidant effects of the peptide by electron spin resonance (ESR) spectrometer, and on t-BHP-induced liver cells damage in Chang cells. The antioxidative activity of the peptide was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, alkyl and superoxide radical scavenging activity using an ESR spectrometer. The half maximal inhibitory concentration (IC50) value of the peptide for hydroxyl, DPPH, alkyl, and superoxide radical scavenging activity were 45.2, 18.5, 31.5, and 33.4 μM, respectively. In addition, the peptide inhibited productions of cell death against t-BHP-induced liver cell damage in Chang cells. It was presumed to be peptide involved in regulating the apoptosis-related gene expression in the cell environment. The present results indicate that the peptide substantially contributes to antioxidative properties in liver cells.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 08/2013; · 2.99 Impact Factor
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    ABSTRACT: The present work describes the protective effects of thymol isolated from Thymus quinquecostatus Celak. against tert-butyl hydroperoxide (t-BHP)-induced oxidative damage through various experiments with Chang liver cells. Thymol significantly protected hepatocytes against t-BHP-induced cell cytotoxicity as demonstrated by increased viability. Furthermore, observation of Hoechst staining, annexin V/PI staining, and expression of Bcl-2 and Bax indicated that thymol inhibited t-BHP-induced Chang cell damage. Further, thymol inhibited the loss of mitochondrial membrane potential in t-BHP-treated Chang cells and prevented oxidative stress-triggered reactive oxygen species (ROS) and lipid peroxidation (malondialdehyde, MDA). Thymol restored the antioxidant capability of hepatocytes including glutathione (GSH) levels which were reduced by t-BHP. These results indicated that thymol prevents oxidative stress-induced damage to liver cells through suppression of ROS and MDA levels and increase of GSH level.
    Journal of Natural Medicines 06/2013; · 1.52 Impact Factor
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    ABSTRACT: Excess oxidant can promote inflammatory responses. Moreover, chronic inflammation accompanied by oxidative stress is connected various steps involved in many diseases. From the aspect, we investigated an antioxidant peptide to prevent inflammatory response against oxidant overexpression. To prepare the peptide, eight proteases were employed for enzymatic hydrolysis, and the antioxidant properties of the hydrolysates were investigated using free radical scavenging activity by electron spin resonance (ESR) spectrometry. Papain hydrolysates, which showed clearly superior free radical scavenging activity, were further purified using consecutive chromatographic methods. Finally, a novel antioxidant peptide was obtained, and the sequence was identified as Ser-Leu-Pro-Ile-Gly-Leu-Met-Ile-Ala-Met at N-terminal. Oral administration of the peptide to mice effectively inhibited malondialdehyde (MDA) levels in a thiobarbituric acid reactive substances (TBARS) assay, and we also confirmed the antioxidative enzyme activities in superoxide dismutase (SOD) and glutathione-s-transferase (GST) assays. This is the first report of an antioxidant peptide derived from the hydrolysate of Mytilus coruscus, and also these results suggest that the peptide possesses potent antioxidant activity, and potential to enhance anti-inflammatory response.
    Fish &amp Shellfish Immunology 05/2013; 34(5):1078–1084. · 2.96 Impact Factor
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    ABSTRACT: Shellfish contain significant levels of high quality protein and are therefore a potential source for biofunctional high-value peptides. To purify a novel anti-inflammatory peptide from Mytilus coruscus (M. coruscus), we applied enzymatic hydrolysis and tangential flow filtration (TFF) and investigated its nitric oxide inhibitory property. To prepare the peptide, eight proteases were employed for enzymatic hydrolysis. Flavouzyme hydrolysates, which showed clearly superior nitric oxide inhibitory activity on lipopolysaccharide (LPS)-stimulated RAW264.7, were further purified using a TFF system and consecutive chromatographic methods. Finally, a novel anti-inflammatory peptide composed of 10 amino acid residues was obtained, and the sequence was identified as Gly-Val-Ser-Leu-Leu-Gln-Gln-Phe-Phe-Leu at N-terminal position. The peptide from M. coruscus effectively inhibited nitric oxide production on macrophage cells. This is the first report of an anti-inflammatory peptide derived from the hydrolysates of M. coruscus.
    Fish &amp Shellfish Immunology 03/2013; · 2.96 Impact Factor
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    ABSTRACT: We purified a novel antioxidant peptide from Ruditapes philippinarum (R. philippinarum) and investigated its free radical scavenging activities. To prepare the peptide, eight proteases were tested for enzymatic hydrolysis. α-chymotrypsin hydrolysate, which showed clearly superior hydroxyl radical scavenging activity (p < 0.05), were further purified using a flow filtration system and consecutive chromatographic methods. Finally, a novel antioxidant peptide was obtained, and the sequence was identified as Ser-Val-Glu-Ile-Gln-Ala-Leu-Cys-Asp-Met. The peptide from R. philippinarum effectively scavenged hydroxyl, DPPH, alkyl and superoxide radicals, with observed IC50 values of 0.042, 0.091, 0.107 and 0.372 mg/ml, respectively. This is the first report of an antioxidant peptide derived from the hydrolysates of R. philippinarum which, further, possesses competitive free radical quenching potential.
    PROCESS BIOCHEMISTRY 02/2013; 48(2):325–330. · 2.41 Impact Factor
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    ABSTRACT: Water and methanolic extracts of Ecklonia cava, a marine brown alga, were prepared by ultrasonic extraction (UE) and conventional extraction (CE) methods. The radical-scavenging activity and the inhibitory effects against hydrogen peroxide ()-induced DNA damage of the extracts were investigated. All extracts prepared by CE exhibited higher total polyphenolic content than that in the extracts prepared by UE. Extraction yield and total phenolic content increased as the UE time increased. The radical-scavenging activities increased as the UE time increased. All extracts prepared by CE exhibited higher 1,1-diphenyl-2-pricrylhydrazyl (DPPH) and hydroxyl radical-scavenging activities than did those prepared by UE. Extracts prepared by UE showed stronger scavenging activities on alkyl radical and than those prepared by CE did. Methanolic extract with UE 12 h (100MEU-12h) and methanolic extract with CE 24 h (100MEC-24h) were selected and evaluated by comet assay for their inhibitory effect against -induced DNA damage. 100MEU-12h showed slightly greater protective effect against -induced DNA damage than 100MEC-24h. Thus, UE can be effectively used as a seaweed extraction technique, and there is potential for scale-up of the extraction process.
    ALGAE. 01/2013; 28(4).
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    ABSTRACT: In the present study, the attenuation of type ІІ diabetes by dieckol, a phlorotannin derivative isolated from brown seaweed, Ecklonia cava was investigated in C57BL/KsJ-db/db, a type ІІ diabetes mouse model. Dieckol was administered intraperitoneal injection at doses of 10 and 20 mg/kg body weight diabetes mice for 14 days. The blood glucose level, serum insulin level and body weight were significantly reduced in the dieckol administered group, compared to that of the saline administered group. Furthermore, reduced thiobarbituric acid reactive substraces (TBARS), as well as increased activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-px) in liver tissues were observed in the dieckol administered group. In addition, increased levels of the phosphorylation of AMPK and Akt were observed in the muscle tissues of the dieckol administered group in a Western blotting analysis. According to the findings of this study, it could be suggested that, dieckol can be developed as a therapeutic agent for type ІІ diabetes.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 12/2012; · 2.99 Impact Factor
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    ABSTRACT: Marine Chlorella ellipsoidea protein was hydrolyzed using Protamex, Kojizyme, Neutrase, Flavourzyme, Alcalase, trypsin, α-chymotrypsin, pepsin and papain. Alcalase-proteolytic hydrolysate exhibited the highest ACE inhibitory activity among them and was fractionated into three ranges of molecular weight (below 5 kDa, 5–10 kDa and above 10 kDa). The below 5 kDa fraction showed the highest ACE inhibitory activity and was used for subsequent purification steps. During consecutive purification, a potent ACE inhibitory peptide from marine C. ellipsoidea, which was composed of 4 amino acids, Val–Glu–Gly–Tyr (MW: 467.2 Da, IC50 value: 128.4 μM), was isolated. Lineweaver–Burk plots suggest that the peptide purified acts as a competitive inhibitor against ACE and stable against gastrointestinal enzymes of pepsin, trypsin and α-chymotrypsin. Furthermore, antihypertensive effect in spontaneously hypertensive rats (SHRs) also revealed that oral administration of purified peptide can decrease systolic blood pressure significantly. The results suggest that marine C. ellipsoidea would be an attractive raw material for the manufacture of antihypertensive nutraceutical ingredients.
    Process Biochemistry. 12/2012; 47(12):2005–2011.
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    ABSTRACT: The peptide was purified from duck skin by-products using a reverse phase high performance liquid chromatography (RP-HPLC), and indentify the antioxidant activity. The sequence of the antioxidative peptide was identified as His-Thr-Val-Gln-Cys-Met-Phe-Gln (molecular weight of 941.43 Da). In addition, the IC50 value of the antioxidative peptide for hydroxyl, DPPH, alkyl, and superoxide radical scavenging activity were 32.6, 22.7, 55.1, and 49.8 μg/ml, respectively. In addition, we also evaluated the protective effects of peptide on 3.5% alcohol-induced damage in normal liver cells. The peptide inhibited productions of reactive oxygen species (ROS), and cell death against alcohol-induced liver cell damage. It was presumed that the peptide was involved in regulation of apoptosis-related pathway in the cell environments.In addition, the antioxidant activity of the gelatin hydrolysates (complex treatment of collagenase and pepsin) was estimated in vivo. The rats were randomly divided into six group (n = 7), and treated with 40% alcohol for15 days, which resulted in lower self-antioxidant capacities as well as increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT) values in blood and liver. Further, antioxidative enzyme (superoxide dismutase; SOD, catalase; CAT, and glutathione peroxidase; GPx) levels in cultured liver cells were increased in the presence of the gelatin hydrolysates.These results indicate that the enzymatic hydrolysates from duck skin by-products possess a potent biological activity.
    Food Research International. 11/2012; 49(1):285–295.
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    ABSTRACT: The present study was designed to evaluate the molecular mechanisms of fucoxanthin against melanoma cell lines (B16F10 cells). Fucoxanthin reduced the proliferation of B16F10 cells in a dose-dependent manner accompanied by the induction of cell cycle arrest during the G(0)/G(1) phase and apoptosis. Fucoxanthin-induced G(0)/G(1) arrest was associated with a marked decrease in the protein expressions of phosphorylated-Rb (retinoblastoma protein), cyclin D (1 and 2) and cyclin-dependent kinase (CDK) 4 and up-regulation of the protein levels of p15(INK4B) and p27(Kip1). Fucoxanthin-induced apoptosis was accompanied with the down-regulation of the protein levels of Bcl-xL, an inhibitor of apoptosis proteins (IAPs), resulting in a sequential activation of caspase-9, caspase-3, and PARP. Furthermore, the anti-tumor effect of fucoxanthin was assessed in vivo in Balb/c mice. Intraperitoneal administration of fucoxanthin significantly inhibited the growth of tumor mass in B16F10 cells implanted mice.
    Environmental toxicology and pharmacology. 10/2012; 35(1):39-46.
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    ABSTRACT: An angiotensin I-converting enzyme (ACE) inhibitory peptide was isolated and identified from hydrolysates of duck skin byproducts. Duck skin byproducts were hydrolyzed using nine proteases (Alcalase, Collagenase, Flavourzyme, Neutrase, papain, pepsin, Protamex, trypsin, and α-chymotrypsin) to produce an antihypertensive peptide. Of the various hydrolysates produced, the α-chymotrypsin hydrolysate exhibited the highest ACE inhibitory activity. The hydrolysate was purified using fast protein liquid chromatography (FPLC) and high-performance liquid chromatography (HPLC). The amino acid sequence of the ACE inhibitory peptide was identified as a hexapeptide Trp-Tyr-Pro-Ala-Ala-Pro, with a molecular weight of 693.90 Da. The peptide had an IC(50) value of 137 μM, and the inhibitory pattern of the purified ACE inhibitor from duck skin byproducts was determined to be competitive by Lineweaver-Burk plots. In addition, the peptide was synthesized and the ACE inhibitory activity was verified in vivo. Spontaneously hypertensive rats (SHR) exhibited significantly decreased blood pressure and heart rate after peptide injection. Taken together, the results suggest that Trp-Tyr-Pro-Ala-Ala-Pro may be useful as a new antihypertensive agent.
    Journal of Agricultural and Food Chemistry 09/2012; · 3.11 Impact Factor

Publication Stats

143 Citations
74.78 Total Impact Points


  • 2005–2014
    • Konkuk University
      • Department of Animal Biotechnology
      Sŏul, Seoul, South Korea
  • 2012
    • Korea Basic Science Institute KBSI
      • Jeju Center
      Seoul, Seoul, South Korea
  • 2011–2012
    • Jeju National University
      • Faculty of Marine Biomedical Sciences
      Cheju, Jeju, South Korea
  • 2009–2012
    • Konkuk University Medical Center
      Changnyeong, South Gyeongsang, South Korea
  • 2008
    • Chonnam National University
      • School of Food Science and Aqualife Medicine
      Yeoju, Gyeonggi, South Korea